docs: Auth-Abschnitt, korrigierte Test-Anleitung, Phase 9

deployment.md bekommt einen eigenen Abschnitt zur Authentifizierung
(Schlüsselweg, geschützte Endpoints, Fehlercodes, der Schalter für
VPN-Instanzen) und eine CORS-Beschreibung, die die Allowlist statt des
alten Wildcards erklärt — inklusive der Tauri-Origins, die sonst am
Preflight scheitern.

Im README steht jetzt der Hinweis, der diese Runde am meisten gekostet
hat: ohne DATABASE_URL_APPVIEW in der Umgebung überspringen sich die
DB-Tests selbst und `cargo test --workspace` meldet grün, ohne sie
ausgeführt zu haben.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013HC9HLrUU1LNwkzp8nkDLX

.env.example

@@ -1,26 +1,46 @@
 # =====================================================
 # maarcadetweet — environment
 # =====================================================
-# Copy to .env and adjust.
+# Copy to .env and adjust. Beide Binaries laden `.env` beim Start
+# selbst (dotenvy); echte Umgebungsvariablen haben Vorrang.
 
 # --- General ---
 RUST_LOG=info,maarcadetweet=debug,sqlx=warn
-APP_ENV=dev
 
 # --- PDS server ---
 PDS_HOST=127.0.0.1
 PDS_PORT=2583
 PDS_PUBLIC_URL=http://127.0.0.1:2583
 PDS_HANDLE_DNS_ZONE=.maarcadetweet.local
-PDS_JWT_SECRET=change-me-to-a-32-byte-random-string-please
+# MUSS Hex sein, >= 32 Bytes ergeben und ein gültiger P-256-Skalar
+# sein (also nicht lauter Nullen) — `jwt_issuer.rs` macht hex::decode()
+# und p256::SecretKey::from_bytes(). Ein ungültiger Wert lässt den
+# Server zwar starten, aber alles, was den Serverschlüssel ableitet,
+# antwortet mit 500: createAccount/createSession/refreshSession UND
+# jeder Record-Write (repo.rs, feed.rs, blob.rs, profile.rs).
+# Der Wert hier ist ein Zufallswert fürs Beispiel — für echte
+# Instanzen einen eigenen erzeugen:
+#   openssl rand -hex 32
+PDS_JWT_SECRET=522084586f3d3abb835d43b7c4726735d78803dd58490f62a92571cd29033a95
+# Wohin die PDS ihre Commits pusht (POST /internal/ingest-commit).
+# Default: APPVIEW_PUBLIC_URL.
+# APPVIEW_INTERNAL_URL=http://127.0.0.1:2584
 
 # --- AppView service ---
 APPVIEW_HOST=127.0.0.1
 APPVIEW_PORT=2584
 APPVIEW_PUBLIC_URL=http://127.0.0.1:2584
 JETSTREAM_URL=wss://jetstream1.us-east.bsky.network/subscribe
-# Collections the AppView will index
+# Collections, die die AppView indexiert. `app.twi.post` ist das
-JETSTREAM_COLLECTIONS=app.bsky.feed.post,app.bsky.feed.like,app.bsky.feed.repost,app.bsky.graph.follow
+# eigene 160-Zeichen-Lexicon und muss mit rein, sonst tauchen eigene
+# Posts nur über den PDS-Push auf; `app.bsky.actor.profile` füttert
+# den Profil-Cache.
+JETSTREAM_COLLECTIONS=app.twi.post,app.bsky.feed.post,app.bsky.feed.like,app.bsky.feed.repost,app.bsky.graph.follow,app.bsky.actor.profile
+# Für den Handle-Sync-Worker: welche PDS nach lokalen Handles gefragt
+# wird. Default: PDS_PUBLIC_URL.
+# PDS_INTERNAL_URL=http://127.0.0.1:2583
+# Intervall des Handle-Sync-Workers in Sekunden (Default: 300).
+# APPVIEW_HANDLE_SYNC_INTERVAL_SECS=60
 
 # --- Databases ---
 DATABASE_URL_PDS=postgres://pds:pds@127.0.0.1:5434/pds
@@ -32,6 +52,9 @@ S3_REGION=us-east-1
 S3_ACCESS_KEY=minioadmin
 S3_SECRET_KEY=minioadmin
 S3_BUCKET_PDS=maarcadetweet-pds
+# Pflichtvariable in AppConfig::from_env(), wird derzeit von keinem
+# Code-Pfad gelesen — muss gesetzt sein, damit der Start nicht
+# fehlschlägt.
 S3_BUCKET_APPVIEW=maarcadetweet-appview
 
 # --- PLC Directory (dev: leave default; can mock) ---
@@ -39,4 +62,36 @@ PLC_DIRECTORY_URL=https://plc.directory
 # PLC_DIRECTORY_URL=http://127.0.0.1:2582
 
 # --- AppView ingest auth (optional, dev ok if unset) ---
+# Wenn gesetzt, muss die PDS denselben Wert als Header
+# `X-Ingest-Secret` mitschicken; ist er nicht gesetzt, nimmt
+# /internal/ingest-commit unauthentifizierte Writes entgegen (jeder,
+# der den Port erreicht, kann Posts/Follows/Notifications fälschen).
+# Die AppView warnt beim Start, solange er fehlt.
 # APPVIEW_INGEST_SECRET=change-me-to-a-shared-secret-between-pds-and-appview
+
+# --- AppView auth (Bearer-Token der PDS) ---
+# Erzwingt ein gültiges Access-JWT auf den privaten Endpoints
+# (/api/notifications, /api/notifications/count,
+# /api/notifications/seen, /api/timeline/home); `sub` im Token muss
+# dem `did`-Parameter entsprechen, sonst 403. Default: true.
+# Den öffentlichen P-256-Schlüssel holt sich die AppView von
+# `PDS_INTERNAL_URL` (sonst `PDS_PUBLIC_URL`) unter
+# /.well-known/did.json — `PDS_JWT_SECRET` verlässt die PDS nie.
+# Auf `false` verhält sich die AppView wie vor der Auth-Einführung
+# (alles öffentlich): nötig für die fail-open-Integrationstests mit
+# synthetischen DIDs und für eine Instanz, die schon per VPN
+# abgeschottet ist. Die AppView warnt beim Start laut, wenn er aus ist.
+# APPVIEW_AUTH_REQUIRED=true
+# Kommaseparierte Allowlist der Browser-Origins, die `/api/*` aufrufen
+# dürfen. Nicht gesetzt = bisheriges Verhalten
+# (`Access-Control-Allow-Origin: *`) plus Startup-Warnung.
+# Der Tauri-Webview hat je nach Plattform eine eigene Origin:
+# macOS/iOS `tauri://localhost`, Windows `http://tauri.localhost`,
+# im Dev-Modus der Vite-Server `http://127.0.0.1:1430`.
+# `Authorization` steht immer in den erlaubten Headern (sonst
+# scheitert der Preflight), `allow_credentials` bleibt aus.
+# APPVIEW_CORS_ORIGINS=tauri://localhost,http://127.0.0.1:1430
+
+# --- Tauri-Client (Build-/Laufzeit-Overrides des Desktop-Clients) ---
+# MAARCADETWEET_PDS_URL=http://127.0.0.1:2583
+# MAARCADETWEET_APPVIEW_URL=http://127.0.0.1:2584

Cargo.lock

@@ -51,7 +51,9 @@ dependencies = [
  "axum",
  "base64",
  "chrono",
+ "dotenvy",
  "futures",
+ "p256",
  "reqwest",
  "rustls",
  "serde",
@@ -1882,6 +1884,7 @@ dependencies = [
  "chrono",
  "ciborium",
  "cid",
+ "dotenvy",
  "hex",
  "k256",
  "p256",

Cargo.toml

@@ -54,6 +54,7 @@ blake3 = "1"
 rand = "0.8"
 rand_core = "0.6"
 hex = "0.4"
+dotenvy = "0.15"
 base64 = "0.22"
 parking_lot = "0.12"
 async-stream = "0.3"

README.md

@@ -12,20 +12,22 @@ crates/
 ├── at-identity/   DID, PLC, Handle-Resolution
 ├── at-mst/        Merkle-Search-Tree
 ├── at-repo/       Repos, Commits, Blöcke, TID-Revs
-├── at-blob/       S3-kompatibler Blob-Store (MinIO)
+├── at-blob/       S3-kompatibler Blob-Store (MinIO) + In-Memory-Store
 ├── at-firehose/   Jetstream-Consumer (WebSocket)
 ├── at-shared/     Config, Errors, DID, Cursor
 ├── pds-server/    axum HTTP PDS (bin)
 └── appview/       Jetstream-Indexer + REST-API (bin)
 
 crates/tauri-app/       Tauri 2 + Svelte 5 + Vite + TS Desktop-Client
-  ├── src/              Svelte-Components (Terminal, StatusBar, NavRail, PostCard, ComposeBox, LoginScreen)
+  ├── src/              Svelte-Components (Terminal, StatusBar, NavRail, PostCard, ComposeBox,
+  │                     LoginScreen, ProfileView, NotificationsView)
   ├── src/lib/styles/   tokens.css (1:1 vom maarcade-Design)
   └── src-tauri/        Rust-IPC-Layer
 
 lexicons/app/twi/post.json     Custom Lexicon mit maxLength: 160
 migrations/pds/                PDS-DB-Schema (users, repos, blobs, sessions, plc_ops)
-migrations/appview/            AppView-DB-Schema (posts, likes, follows, timeline_cache, jetstream_cursor)
+migrations/appview/            AppView-DB-Schema (posts, likes, follows, notifications, profiles, jetstream_cursor)
+docs/                          Deployment, Architektur, Tauri-Release (siehe unten)
 ```
 
 ## Setup
@@ -34,7 +36,8 @@ migrations/appview/            AppView-DB-Schema (posts, likes, follows, timelin
 # 1) Datenbanken + MinIO starten
 docker compose up -d
 
-# 2) Umgebungsvariablen
+# 2) Umgebungsvariablen — beide Binaries laden .env selbst (dotenvy).
+#    PDS_JWT_SECRET muss Hex sein: openssl rand -hex 32
 cp .env.example .env
 
 # 3) Workspace kompilieren + Tests
@@ -61,26 +64,57 @@ cargo run -p appview
 | 2  MST + Repo (Spec-konforme CBOR-Encoding) | ✅ done — `encode_key` = `base64url(sha256(raw_key))` per atproto-Spec, `split_around`/`wrap_with_split` threaden den recursive right_sub korrekt als `k_tree` weiter. 27 MST + 13 Repo + 4 Commit Tests grün. |
 | 3  PDS-Server (com.atproto.* XRPC) | ✅ done — createAccount/Session/Refresh, createRecord/deleteRecord, like/repost, follow |
 | 4  AppView-Foundation (Jetstream-Index) | ✅ done — Jetstream-Indexer + identity-Event-Backfill + PLC-handle-sync-Worker |
-| 5  AppView-REST-API | ✅ done — timeline, profile (by-did + by-handle), search, post-by-uri, thread-context |
+| 5  AppView-REST-API | ✅ done — timeline, profile (by-did + by-handle), search, post-by-uri, thread, notifications, followers/following |
 | 6  Tauri-UI-Logik an Backend koppeln | ✅ done — LoginScreen, NavRail, PostCard, ComposeBox, Profile/Compose/Search/Settings-Views |
-| 7  Polish (Tray, Notifications, Auto-Update) | ✅ done — Tray-Icon custom (`tauri::include_image!`), Notification-Click navigiert via `app://notification`-Event + `openThread`-Helper zu Thread-Detail, Auto-Update in Dev deaktiviert (siehe `_comment` in `tauri.conf.json` für Production-Setup) |
+| 7  Polish (Tray, Notifications, Auto-Update) | ✅ done — Tray-Icon custom (`tauri::include_image!`), Notification-Click navigiert via `app://notification`-Event + `openThread`-Helper zu Thread-Detail, Auto-Update in Dev inert (Production-Weg: [`docs/tauri-release.md`](docs/tauri-release.md)) |
+| 8  Social-Graph + Benachrichtigungen | ✅ done — `notifications`-Tabelle, Schreibpfad im Jetstream-Indexer (idempotent, keine Selbst-Notifications), `/api/notifications[/count|/seen]`, `/api/followers`, `/api/following`, eigene `/api/thread`-Route; im Client Notifications-View mit Unread-Badge und klickbare Follower-/Following-Listen im Profil |
+| 9  Auth + Performance | ✅ done — AppView prüft Bearer-Tokens (ES256, Schlüssel aus dem neuen `/.well-known/did.json` der PDS, fail closed); Timeline und Notifications nur noch für die eigene DID; CORS-Allowlist statt `Any`; Indizes für Handle-Lookup und Cold-Start-Feed |
 
 ## Tests
 
-```
+```bash
-running 16 tests (at-crypto)
+cargo test --workspace                     # Rust: PDS, AppView, at-* Crates
-test result: ok. 16 passed; 0 failed; 0 ignored
+cd crates/tauri-app && npx vitest run      # Svelte/TS
-running 3 tests (at-lexicon)
+cd crates/tauri-app/src-tauri && cargo test # Tauri-IPC (eigener Workspace!)
-test result: ok. 3 passed; 0 failed
-running 2 tests (at-shared)
-test result: ok. 2 passed; 0 failed
-running 2 tests (at-repo)
-test result: ok. 2 passed; 0 failed
-running 4 tests (at-crypto plc_op — Phase 1)
-test result: ok. 4 passed; 0 failed
 ```
 
-Der zuvor als "geplant für Phase 1" markierte `jwt::issue_and_verify`-Test wurde zwischenzeitlich grün gezogen (P-256-PKCS#8-PEM-Encoder ist über `p256::pkcs8::EncodePrivateKey` da).
+Stand zuletzt gegen den lokalen Dev-Stack (docker compose + laufender PDS + AppView):
+Rust-Workspace grün (u.a. 27 MST, 24 PDS-Integration, 49 AppView-Lib, 14 AppView-Integration),
+Frontend grün. Zwei Vorbehalte:
+
+* Die DB-gestützten Tests sind *fail-open*: **ohne `DATABASE_URL_APPVIEW` in der
+  Umgebung überspringen sie sich selbst** und melden das nur auf stderr. `cargo test
+  --workspace` in einer nackten Shell meldet dann grün, ohne sie ausgeführt zu haben —
+  für einen aussagekräftigen Lauf `set -a; . ./.env; set +a` voranstellen und PDS +
+  AppView laufen lassen.
+* Läuft die Auth (Default), holen sich die Integrationstests echte Tokens von der PDS
+  bzw. signieren sie aus `PDS_JWT_SECRET`; ohne erreichbare PDS überspringen sie.
+
+`crates/tauri-app/src-tauri` hat ein eigenes `[workspace]` und ist **nicht** Teil des
+Root-Workspace; `cargo test --workspace` von oben erfasst den IPC-Layer nicht.
+
+## Dokumentation
+
+| Datei | Inhalt |
+|---|---|
+| [`docs/architecture.md`](docs/architecture.md) | Crate-Verantwortlichkeiten, Datenfluss PDS → Jetstream → AppView → Client, Tabellenübersicht |
+| [`docs/deployment.md`](docs/deployment.md) | Betrieb: docker compose, Migrationen, alle Env-Variablen, Release-Build, systemd-Units, Reverse-Proxy, Health-Checks |
+| [`docs/tauri-release.md`](docs/tauri-release.md) | Signing-Keys, Updater-Config, `latest.json`, Build pro Plattform, Artefaktpfade |
+
+## Bekannte Lücken
+
+* Die eigene PDS speist **keinen** Firehose (`com.atproto.sync.subscribeRepos` fehlt) —
+  eigene Records erreichen die AppView nur über den Best-Effort-Push
+  `POST /internal/ingest-commit`.
+* `aud` wird beim Token-Check nicht validiert (Signatur, Ablauf, `scope` und
+  `sub` schon).
+* Notifications werden nie gelöscht: Unlike/Unfollow lässt die Zeile stehen, und der
+  Dedupe-Key macht sie „einmal pro (Empfänger, Autor, Art, Subject) für immer".
+* Auto-Update ist nur dokumentiert, nicht verdrahtet: niemand ruft `check()` auf, das
+  Updater-Plugin ist nicht installiert (siehe `docs/tauri-release.md`).
+* Reply-Notifications gehen verloren, wenn die Antwort vor ihrem Parent indiziert wird
+  (kein Nachlauf) — bei Jetstream möglich.
+* `at-blob` spricht MinIO ohne Signature V4 — echtes AWS S3 funktioniert damit nicht.
 
 ## Design
 

crates/appview/Cargo.toml

@@ -19,6 +19,7 @@ path = "src/main.rs"
 
 [dependencies]
 tokio = { workspace = true }
+dotenvy = { workspace = true }
 axum = { workspace = true }
 tower = { workspace = true }
 tower-http = { workspace = true }
@@ -34,6 +35,7 @@ at-shared = { workspace = true }
 at-firehose = { workspace = true }
 at-crypto = { workspace = true }
 at-identity = { workspace = true }
+reqwest = { workspace = true }
 uuid = { workspace = true }
 rustls = { version = "0.23", default-features = false, features = ["ring", "std", "logging", "tls12"] }
 base64 = { workspace = true }
@@ -44,3 +46,7 @@ tokio = { workspace = true }
 reqwest = { workspace = true }
 serde_json = { workspace = true }
 uuid = { workspace = true }
+# Unit tests in `src/auth.rs` build a P-256 verification key in the
+# same `0x8012 + uncompressed point` encoding the PDS publishes, which
+# needs the curve's `ToEncodedPoint`.
+p256 = { workspace = true }

crates/appview/src/auth.rs

@@ -0,0 +1,659 @@
+//! Bearer-token authentication for the AppView's private endpoints.
+//!
+//! ## What is being proven
+//!
+//! The PDS already issues an ES256 access JWT on
+//! `com.atproto.server.createSession` / `createAccount`. That token
+//! carries `sub = <did>`, `scope = "com.atproto.access"` and
+//! `aud = "did:web:appview.maarcadetweet.local"` — it was always meant
+//! to be presented *here*. All the AppView has to do is verify the
+//! signature and read `sub`.
+//!
+//! ## Where the key comes from
+//!
+//! Verifying an ES256 signature needs only the public half of the PDS's
+//! P-256 key. The PDS publishes it in its DID document at
+//! `GET /.well-known/did.json` (see `pds-server/src/main.rs`), so
+//! `PDS_JWT_SECRET` never leaves the PDS process. We fetch that
+//! document once, cache the `publicKeyMultibase` behind an `RwLock`,
+//! and re-fetch on a verification failure so an operator can rotate
+//! `PDS_JWT_SECRET` without restarting the AppView.
+//!
+//! Two failure modes are deliberately handled differently:
+//!
+//!  - **PDS unreachable at startup.** The AppView has always booted
+//!    independently of the PDS (it indexes the firehose, which has
+//!    nothing to do with the local PDS), and a crash-loop on a
+//!    colocated service that happens to boot second would be a
+//!    self-inflicted outage. So startup only *warns*; the first
+//!    authenticated request retries the fetch.
+//!  - **PDS unreachable when a token must be checked.** There is no
+//!    safe way to guess, so the request gets a `503`. Fail closed —
+//!    never fail open.
+//!
+//! ## Error contract
+//!
+//! The body shape matches every other AppView error
+//! (`{"error": …, "message": …}`). The `error` codes are load-bearing:
+//!
+//! | case                                   | status | `error`           |
+//! |----------------------------------------|--------|-------------------|
+//! | no / malformed `Authorization` header  | 401    | `AuthMissing`     |
+//! | bad signature, expired, wrong `scope`  | 401    | `TokenInvalid`    |
+//! | valid token, but `sub` ≠ requested did | 403    | `Forbidden`       |
+//! | PDS key not obtainable                 | 503    | `AuthUnavailable` |
+//!
+//! **`TokenInvalid` is a contract with the desktop client**: seeing it,
+//! the client refreshes its access JWT (`com.atproto.server.refreshSession`)
+//! and retries the request once. Renaming it silently logs every user
+//! out an hour after login.
+
+use at_crypto::jwt::JwtClaims;
+use axum::async_trait;
+use axum::extract::FromRequestParts;
+use axum::http::request::Parts;
+use axum::http::{HeaderMap, StatusCode};
+use axum::Json;
+use serde_json::{json, Value};
+use std::time::{Duration, Instant};
+use tokio::sync::RwLock;
+use tracing::{debug, warn};
+
+use crate::state::AppState;
+
+/// The scope an *access* token carries. Refresh tokens are minted with
+/// `com.atproto.refresh` by the same key, so without this check a
+/// refresh token — which lives for 90 days instead of an hour — would
+/// be accepted as a session credential everywhere.
+const ACCESS_SCOPE: &str = "com.atproto.access";
+
+/// Minimum spacing between two key re-fetches triggered by a failed
+/// verification.
+///
+/// Re-fetching on failure is what makes key rotation work without a
+/// restart. Doing it on *every* failure would also hand anyone who can
+/// reach the AppView a free amplifier: a stream of garbage tokens
+/// becomes a stream of requests to the PDS. One re-fetch per minute is
+/// far quicker than any plausible rotation cadence needs and costs the
+/// PDS nothing.
+const KEY_REFETCH_MIN_INTERVAL: Duration = Duration::from_secs(60);
+
+/// HTTP timeout for the DID-document fetch. The PDS is colocated; if it
+/// doesn't answer in two seconds it isn't answering, and a request
+/// blocked on auth is a request the user is staring at.
+const DID_DOC_TIMEOUT: Duration = Duration::from_secs(2);
+
+// -- error type --------------------------------------------------------------
+
+/// Everything that can go wrong between "a request arrived" and "we know
+/// which DID it belongs to". Converted into the AppView's standard error
+/// body by [`AuthError::into_response_parts`].
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum AuthError {
+    /// No `Authorization` header, or one that isn't `Bearer <token>`.
+    Missing,
+    /// Signature, expiry or scope check failed. The client's cue to
+    /// refresh its access token and retry.
+    Invalid(String),
+    /// Authenticated fine, but the token belongs to somebody else.
+    Forbidden,
+    /// We could not obtain the PDS's public key, so we cannot decide.
+    Unavailable(String),
+}
+
+impl AuthError {
+    pub fn into_response_parts(self) -> (StatusCode, Json<Value>) {
+        let (status, code, message) = match self {
+            AuthError::Missing => (
+                StatusCode::UNAUTHORIZED,
+                "AuthMissing",
+                "missing Authorization: Bearer header".to_string(),
+            ),
+            AuthError::Invalid(detail) => {
+                (StatusCode::UNAUTHORIZED, "TokenInvalid", detail)
+            }
+            AuthError::Forbidden => (
+                StatusCode::FORBIDDEN,
+                "Forbidden",
+                "token sub does not match the requested did".to_string(),
+            ),
+            AuthError::Unavailable(detail) => (
+                StatusCode::SERVICE_UNAVAILABLE,
+                "AuthUnavailable",
+                format!("cannot verify tokens: {detail}"),
+            ),
+        };
+        (
+            status,
+            Json(json!({
+                "error": code,
+                "message": message,
+            })),
+        )
+    }
+}
+
+impl From<AuthError> for (StatusCode, Json<Value>) {
+    fn from(e: AuthError) -> Self {
+        e.into_response_parts()
+    }
+}
+
+// -- key cache ---------------------------------------------------------------
+
+#[derive(Default)]
+struct CachedKey {
+    multibase: Option<String>,
+    /// When we last *attempted* a fetch — successful or not. Throttles
+    /// the on-failure refresh path; see [`KEY_REFETCH_MIN_INTERVAL`].
+    last_attempt: Option<Instant>,
+}
+
+/// The PDS signing key, lazily fetched and cached.
+///
+/// Lives in [`AppState`] behind an `Arc`, so all handlers share one
+/// cache and one HTTP client.
+pub struct PdsKeys {
+    http: reqwest::Client,
+    /// Fully-qualified URL of the PDS's DID document.
+    did_doc_url: String,
+    inner: RwLock<CachedKey>,
+}
+
+impl PdsKeys {
+    /// Build a cache pointed at `base_url` (no trailing slash required).
+    pub fn new(base_url: &str) -> Self {
+        let http = reqwest::Client::builder()
+            .timeout(DID_DOC_TIMEOUT)
+            .build()
+            .expect("reqwest client build should never fail");
+        Self {
+            http,
+            did_doc_url: format!(
+                "{}/.well-known/did.json",
+                base_url.trim_end_matches('/')
+            ),
+            inner: RwLock::new(CachedKey::default()),
+        }
+    }
+
+    /// Same PDS the handle-sync worker talks to: `PDS_INTERNAL_URL`
+    /// when set, else `PDS_PUBLIC_URL`.
+    pub fn from_config(cfg: &at_shared::config::AppConfig) -> Self {
+        Self::new(&cfg.pds_base_url())
+    }
+
+    pub fn did_doc_url(&self) -> &str {
+        &self.did_doc_url
+    }
+
+    /// The cached key, if we have ever fetched one.
+    pub async fn cached(&self) -> Option<String> {
+        self.inner.read().await.multibase.clone()
+    }
+
+    /// Fetch the DID document and replace the cached key.
+    ///
+    /// Called once at startup (best effort), on the first authenticated
+    /// request if startup failed, and — throttled — after a failed
+    /// verification.
+    pub async fn refresh(&self) -> anyhow::Result<String> {
+        // Record the attempt before the await so two concurrent
+        // failures can't both decide they're the first one.
+        self.inner.write().await.last_attempt = Some(Instant::now());
+
+        let resp = self.http.get(&self.did_doc_url).send().await?;
+        if !resp.status().is_success() {
+            anyhow::bail!(
+                "{} returned {}",
+                self.did_doc_url,
+                resp.status().as_u16()
+            );
+        }
+        let doc: Value = resp.json().await?;
+        let key = extract_public_key_multibase(&doc)?;
+        {
+            let mut guard = self.inner.write().await;
+            guard.multibase = Some(key.clone());
+        }
+        debug!(url = %self.did_doc_url, "loaded PDS signing key");
+        Ok(key)
+    }
+
+    /// The key to verify with, fetching it if we don't have one yet.
+    async fn key_or_fetch(&self) -> Result<String, AuthError> {
+        if let Some(k) = self.cached().await {
+            return Ok(k);
+        }
+        self.refresh().await.map_err(|e| {
+            warn!(url = %self.did_doc_url, error = %e, "PDS signing key unavailable");
+            AuthError::Unavailable(format!(
+                "PDS did document at {} not reachable: {e}",
+                self.did_doc_url
+            ))
+        })
+    }
+
+    /// Re-fetch after a verification failure, at most once per
+    /// [`KEY_REFETCH_MIN_INTERVAL`]. Returns the new key only when it
+    /// actually differs from `stale` — re-running the same failing
+    /// verification against an unchanged key proves nothing.
+    async fn refetch_if_stale(&self, stale: &str) -> Option<String> {
+        {
+            let guard = self.inner.read().await;
+            if let Some(last) = guard.last_attempt {
+                if last.elapsed() < KEY_REFETCH_MIN_INTERVAL {
+                    return None;
+                }
+            }
+        }
+        match self.refresh().await {
+            Ok(fresh) if fresh != stale => {
+                warn!("PDS signing key changed; re-verifying with the rotated key");
+                Some(fresh)
+            }
+            Ok(_) => None,
+            Err(e) => {
+                warn!(error = %e, "PDS key re-fetch after verification failure failed");
+                None
+            }
+        }
+    }
+
+    /// Verify an access token and return its claims.
+    ///
+    /// Retries exactly once against a freshly fetched key, so a rotated
+    /// `PDS_JWT_SECRET` costs one extra HTTP round trip rather than a
+    /// restart.
+    pub async fn verify_access_token(&self, token: &str) -> Result<JwtClaims, AuthError> {
+        let key = self.key_or_fetch().await?;
+        match verify_with_key(token, &key) {
+            Ok(claims) => Ok(claims),
+            Err(first) => {
+                let Some(fresh) = self.refetch_if_stale(&key).await else {
+                    return Err(first);
+                };
+                verify_with_key(token, &fresh).map_err(|_| first)
+            }
+        }
+    }
+}
+
+/// Pull `verificationMethod[].publicKeyMultibase` out of a DID document.
+///
+/// We take the first entry that carries a `publicKeyMultibase` rather
+/// than insisting on a fragment name: the PDS writes `#atproto`, but a
+/// document served by a proxy or a future PDS version may order or name
+/// its methods differently, and any key in the document is a key the
+/// controller published for itself. A document with none is an error,
+/// not an empty key — silently caching `""` would turn every later
+/// verification into a confusing signature failure.
+fn extract_public_key_multibase(doc: &Value) -> anyhow::Result<String> {
+    let methods = doc
+        .get("verificationMethod")
+        .and_then(|v| v.as_array())
+        .ok_or_else(|| anyhow::anyhow!("did document has no verificationMethod array"))?;
+    for m in methods {
+        if let Some(k) = m.get("publicKeyMultibase").and_then(|v| v.as_str()) {
+            if !k.is_empty() {
+                return Ok(k.to_string());
+            }
+        }
+    }
+    anyhow::bail!("did document has no verificationMethod with publicKeyMultibase")
+}
+
+/// Signature + expiry + scope check against one specific key.
+///
+/// `verify_jwt` handles the ES256 signature and `exp` (with a 30 s
+/// leeway for clock skew); the scope check is ours, and it is the line
+/// that keeps a 90-day refresh token from working as a session
+/// credential.
+fn verify_with_key(token: &str, pubkey_multibase: &str) -> Result<JwtClaims, AuthError> {
+    let claims = at_crypto::jwt::verify_jwt(token, pubkey_multibase)
+        .map_err(|e| AuthError::Invalid(format!("invalid token: {e}")))?;
+    match claims.scope.as_deref() {
+        Some(ACCESS_SCOPE) => Ok(claims),
+        other => Err(AuthError::Invalid(format!(
+            "token scope {:?} is not {ACCESS_SCOPE}",
+            other.unwrap_or("<none>")
+        ))),
+    }
+}
+
+/// Extract the bearer token from an `Authorization` header.
+///
+/// The scheme match is case-insensitive (RFC 7235 says it is) — some
+/// HTTP clients send `bearer`.
+fn bearer_token(headers: &HeaderMap) -> Result<String, AuthError> {
+    let raw = headers
+        .get("authorization")
+        .and_then(|v| v.to_str().ok())
+        .ok_or(AuthError::Missing)?;
+    let (scheme, token) = raw.split_once(' ').ok_or(AuthError::Missing)?;
+    if !scheme.eq_ignore_ascii_case("bearer") {
+        return Err(AuthError::Missing);
+    }
+    let token = token.trim();
+    if token.is_empty() {
+        return Err(AuthError::Missing);
+    }
+    Ok(token.to_string())
+}
+
+// -- extractor ---------------------------------------------------------------
+
+/// The authenticated DID of the caller.
+///
+/// `None` means auth is switched off for this instance
+/// (`APPVIEW_AUTH_REQUIRED=false`) — *not* "anonymous but allowed
+/// through". When auth is on, this is always `Some` by construction:
+/// the extractor rejects the request otherwise.
+///
+/// Handlers must still call [`AuthedDid::ensure_matches`] with the DID
+/// the request asks about. Proving *who you are* is not the same as
+/// proving *whose notifications you may read*.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct AuthedDid(pub Option<String>);
+
+impl AuthedDid {
+    /// 403 unless the token's `sub` is the DID the request targets.
+    ///
+    /// With auth disabled this is a no-op, which is exactly what
+    /// `APPVIEW_AUTH_REQUIRED=false` means.
+    pub fn ensure_matches(&self, did: &str) -> Result<(), (StatusCode, Json<Value>)> {
+        match self.0.as_deref() {
+            None => Ok(()),
+            Some(sub) if sub == did => Ok(()),
+            Some(_) => Err(AuthError::Forbidden.into_response_parts()),
+        }
+    }
+
+    /// The caller's DID, if authenticated.
+    ///
+    /// No handler needs it yet — every private endpoint takes the DID
+    /// as a parameter and compares it — but an endpoint that acts
+    /// purely on "whoever is calling" would read it here instead of
+    /// trusting a query parameter.
+    #[allow(dead_code)]
+    pub fn did(&self) -> Option<&str> {
+        self.0.as_deref()
+    }
+}
+
+#[async_trait]
+impl FromRequestParts<AppState> for AuthedDid {
+    type Rejection = (StatusCode, Json<Value>);
+
+    async fn from_request_parts(
+        parts: &mut Parts,
+        state: &AppState,
+    ) -> Result<Self, Self::Rejection> {
+        if !state.cfg.appview_auth_required {
+            // Opt-out instance. The startup log says so in capitals.
+            return Ok(AuthedDid(None));
+        }
+        let token = bearer_token(&parts.headers).map_err(AuthError::into_response_parts)?;
+        let claims = state
+            .pds_keys
+            .verify_access_token(&token)
+            .await
+            .map_err(AuthError::into_response_parts)?;
+        Ok(AuthedDid(Some(claims.sub)))
+    }
+}
+
+// -- startup posture ---------------------------------------------------------
+
+/// Log, once at boot, every way this instance is configured to be less
+/// strict than the defaults.
+///
+/// All three of these are legitimate configurations — a VPN-only
+/// deployment, a dev box, a single-machine setup — and all three are
+/// also exactly what an accidentally-public instance looks like. The
+/// only defence that survives a hurried deployment is a log line the
+/// operator cannot miss, so each one is a `warn!` naming the variable
+/// that turns it back on.
+pub fn log_startup_posture(cfg: &at_shared::config::AppConfig) {
+    if !cfg.appview_auth_required {
+        warn!(
+            "APPVIEW_AUTH_REQUIRED=false — /api/notifications* and \
+             /api/timeline/home are served to ANY caller for ANY did. \
+             Only safe when this instance is unreachable from untrusted \
+             networks."
+        );
+    }
+    if cfg.appview_cors_origins.is_empty() {
+        warn!(
+            "APPVIEW_CORS_ORIGINS unset — sending Access-Control-Allow-Origin: * \
+             so any web page can call this AppView from a browser. Set it to the \
+             origins your client actually uses, e.g. \
+             'tauri://localhost,http://127.0.0.1:1430'."
+        );
+    }
+    if cfg.appview_ingest_secret.is_none() {
+        warn!(
+            "APPVIEW_INGEST_SECRET unset — POST /internal/ingest-commit accepts \
+             unauthenticated writes into the index (anyone who can reach this port \
+             can forge posts, follows and notifications). Set the same value here \
+             and on the PDS."
+        );
+    }
+}
+
+// -- tests -------------------------------------------------------------------
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use at_crypto::ecdsa::P256Keypair;
+    use at_crypto::jwt::{issue_jwt, JwtClaims};
+    use axum::http::HeaderValue;
+
+    /// A throwaway server key plus its `publicKeyMultibase`, in the
+    /// exact encoding the PDS publishes: `0x8012` (P-256) followed by
+    /// the *uncompressed* affine coordinates. `P256Keypair::generate`
+    /// stores a compressed point, which `verify_jwt` cannot decode — so
+    /// this mirrors `pds-server`'s `server_p256_keypair`.
+    fn test_key() -> (P256Keypair, String) {
+        let kp = P256Keypair::generate().unwrap();
+        let vk = kp.verifying_key().unwrap();
+        let pt = vk.to_encoded_point(false);
+        let mut raw = vec![0x80u8, 0x12u8];
+        raw.extend_from_slice(pt.x().unwrap());
+        raw.extend_from_slice(pt.y().unwrap());
+        let multibase = at_crypto::multibase_util::encode_b58btc(&raw);
+        (kp, multibase)
+    }
+
+    fn mint(kp: &P256Keypair, did: &str, scope: &str, ttl_secs: i64) -> String {
+        let now = chrono::Utc::now().timestamp();
+        issue_jwt(
+            kp,
+            &JwtClaims {
+                iss: "did:web:127.0.0.1%3A2583".into(),
+                sub: did.into(),
+                aud: "did:web:appview.maarcadetweet.local".into(),
+                iat: now - 1,
+                exp: now + ttl_secs,
+                jti: None,
+                scope: Some(scope.into()),
+            },
+        )
+        .unwrap()
+    }
+
+    fn header_map(value: &str) -> HeaderMap {
+        let mut h = HeaderMap::new();
+        h.insert("authorization", HeaderValue::from_str(value).unwrap());
+        h
+    }
+
+    #[test]
+    fn missing_header_is_auth_missing() {
+        assert_eq!(bearer_token(&HeaderMap::new()), Err(AuthError::Missing));
+    }
+
+    #[test]
+    fn malformed_header_is_auth_missing() {
+        // No scheme, wrong scheme, and an empty token all read as
+        // "the client never presented a credential" — 401 AuthMissing,
+        // not TokenInvalid, so the client re-authenticates instead of
+        // burning a refresh round trip.
+        assert_eq!(bearer_token(&header_map("abc.def.ghi")), Err(AuthError::Missing));
+        assert_eq!(bearer_token(&header_map("Basic dXNlcjpwdw==")), Err(AuthError::Missing));
+        assert_eq!(bearer_token(&header_map("Bearer   ")), Err(AuthError::Missing));
+    }
+
+    #[test]
+    fn bearer_scheme_is_case_insensitive() {
+        assert_eq!(bearer_token(&header_map("bearer tok")).unwrap(), "tok");
+        assert_eq!(bearer_token(&header_map("Bearer tok")).unwrap(), "tok");
+    }
+
+    #[test]
+    fn error_bodies_carry_the_documented_codes() {
+        // These strings are a contract: the desktop client keys its
+        // "refresh and retry" behaviour off `TokenInvalid`.
+        let (s, b) = AuthError::Missing.into_response_parts();
+        assert_eq!(s, StatusCode::UNAUTHORIZED);
+        assert_eq!(b.0["error"], "AuthMissing");
+        let (s, b) = AuthError::Invalid("x".into()).into_response_parts();
+        assert_eq!(s, StatusCode::UNAUTHORIZED);
+        assert_eq!(b.0["error"], "TokenInvalid");
+        let (s, b) = AuthError::Forbidden.into_response_parts();
+        assert_eq!(s, StatusCode::FORBIDDEN);
+        assert_eq!(b.0["error"], "Forbidden");
+        let (s, b) = AuthError::Unavailable("pds down".into()).into_response_parts();
+        assert_eq!(s, StatusCode::SERVICE_UNAVAILABLE);
+        assert_eq!(b.0["error"], "AuthUnavailable");
+        // Every body carries both fields the client parses.
+        assert!(b.0["message"].as_str().unwrap().contains("pds down"));
+    }
+
+    #[test]
+    fn valid_access_token_verifies() {
+        let (kp, mb) = test_key();
+        let token = mint(&kp, "did:plc:alice", ACCESS_SCOPE, 3600);
+        let claims = verify_with_key(&token, &mb).unwrap();
+        assert_eq!(claims.sub, "did:plc:alice");
+    }
+
+    #[test]
+    fn garbage_token_is_invalid() {
+        let (_, mb) = test_key();
+        let err = verify_with_key("not-a-jwt", &mb).unwrap_err();
+        assert!(matches!(err, AuthError::Invalid(_)));
+    }
+
+    #[test]
+    fn token_signed_by_another_key_is_invalid() {
+        let (kp, _) = test_key();
+        let (_, other_mb) = test_key();
+        let token = mint(&kp, "did:plc:alice", ACCESS_SCOPE, 3600);
+        assert!(matches!(
+            verify_with_key(&token, &other_mb).unwrap_err(),
+            AuthError::Invalid(_)
+        ));
+    }
+
+    #[test]
+    fn refresh_scope_is_rejected() {
+        // The refresh token is signed by the same key and lives 90
+        // days. Without the scope check it would be a session token.
+        let (kp, mb) = test_key();
+        let token = mint(&kp, "did:plc:alice", "com.atproto.refresh", 3600);
+        let err = verify_with_key(&token, &mb).unwrap_err();
+        match err {
+            AuthError::Invalid(msg) => assert!(msg.contains("com.atproto.refresh")),
+            other => panic!("expected Invalid, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn expired_token_is_rejected() {
+        // Beyond `verify_jwt`'s 30 s leeway.
+        let (kp, mb) = test_key();
+        let token = mint(&kp, "did:plc:alice", ACCESS_SCOPE, -120);
+        assert!(matches!(
+            verify_with_key(&token, &mb).unwrap_err(),
+            AuthError::Invalid(_)
+        ));
+    }
+
+    #[test]
+    fn ensure_matches_enforces_sub_equals_did() {
+        let me = AuthedDid(Some("did:plc:alice".into()));
+        assert!(me.ensure_matches("did:plc:alice").is_ok());
+        let (status, body) = me.ensure_matches("did:plc:bob").unwrap_err();
+        assert_eq!(status, StatusCode::FORBIDDEN);
+        assert_eq!(body.0["error"], "Forbidden");
+        // A prefix of the real DID must not pass.
+        assert!(me.ensure_matches("did:plc:ali").is_err());
+    }
+
+    #[test]
+    fn ensure_matches_is_a_noop_when_auth_disabled() {
+        let off = AuthedDid(None);
+        assert!(off.ensure_matches("did:plc:anyone").is_ok());
+        assert_eq!(off.did(), None);
+    }
+
+    #[test]
+    fn did_doc_key_extraction() {
+        let doc = json!({
+            "id": "did:web:127.0.0.1%3A2583",
+            "verificationMethod": [{
+                "id": "did:web:127.0.0.1%3A2583#atproto",
+                "type": "Multikey",
+                "controller": "did:web:127.0.0.1%3A2583",
+                "publicKeyMultibase": "zQ3shokFTS3brHcDQrn82RUDfCZESWL1ZdCEJwekUDPQiYBme"
+            }]
+        });
+        assert_eq!(
+            extract_public_key_multibase(&doc).unwrap(),
+            "zQ3shokFTS3brHcDQrn82RUDfCZESWL1ZdCEJwekUDPQiYBme"
+        );
+
+        // A document without a usable key must error rather than cache
+        // an empty string.
+        assert!(extract_public_key_multibase(&json!({})).is_err());
+        assert!(extract_public_key_multibase(&json!({
+            "verificationMethod": [{"id": "#x", "type": "Multikey"}]
+        }))
+        .is_err());
+        assert!(extract_public_key_multibase(&json!({
+            "verificationMethod": [{"publicKeyMultibase": ""}]
+        }))
+        .is_err());
+    }
+
+    #[test]
+    fn did_doc_url_is_built_from_the_base_url() {
+        assert_eq!(
+            PdsKeys::new("http://127.0.0.1:2583").did_doc_url(),
+            "http://127.0.0.1:2583/.well-known/did.json"
+        );
+        // A trailing slash must not produce a double slash — some
+        // servers 404 on it.
+        assert_eq!(
+            PdsKeys::new("http://pds:3000/").did_doc_url(),
+            "http://pds:3000/.well-known/did.json"
+        );
+    }
+
+    #[tokio::test]
+    async fn verification_fails_closed_when_the_pds_is_unreachable() {
+        // Port 1 on loopback: nothing listens there, so the fetch fails
+        // fast. The result must be a 503, never a pass-through.
+        let keys = PdsKeys::new("http://127.0.0.1:1");
+        let err = keys.verify_access_token("whatever").await.unwrap_err();
+        assert!(
+            matches!(err, AuthError::Unavailable(_)),
+            "expected Unavailable, got {err:?}"
+        );
+        let (status, body) = err.into_response_parts();
+        assert_eq!(status, StatusCode::SERVICE_UNAVAILABLE);
+        assert_eq!(body.0["error"], "AuthUnavailable");
+    }
+}

crates/appview/src/handle_sync.rs

@@ -147,7 +147,17 @@ impl HandleSyncWorker {
     /// `handle` is filled, so a DID that becomes resolvable later
     /// (e.g. the user joins the local PDS) gets re-attempted.
     pub async fn run_once(&self) -> Result<SyncReport> {
-        let dids: Vec<(String,)> = sqlx::query_as(
+        let dids = self.select_candidates().await?;
+        self.resolve_batch(dids).await
+    }
+
+    /// The SELECT half of [`Self::run_once`]: up to [`BATCH_SIZE`]
+    /// distinct DIDs still waiting for a handle.
+    ///
+    /// Public so integration tests can assert on the batch cap without
+    /// depending on what else the live indexer left pending.
+    pub async fn select_candidates(&self) -> Result<Vec<String>> {
+        let rows: Vec<(String,)> = sqlx::query_as(
             r#"SELECT DISTINCT did
                FROM posts
                WHERE handle = ''
@@ -159,7 +169,18 @@ impl HandleSyncWorker {
         .bind(BATCH_SIZE)
         .fetch_all(&self.db)
         .await?;
+        Ok(rows.into_iter().map(|(did,)| did).collect())
+    }
 
+    /// The resolve-and-write half of [`Self::run_once`], split out so
+    /// tests can drive it with a DID set of their own.
+    ///
+    /// `run_once`'s own scan is global and capped at [`BATCH_SIZE`],
+    /// so against a shared database with a live indexer a test's
+    /// freshly seeded DID may simply not make the batch — which made
+    /// the dispatch tests fail for reasons that had nothing to do with
+    /// dispatch. Passing the DIDs in removes that coupling.
+    pub async fn resolve_batch(&self, dids: Vec<String>) -> Result<SyncReport> {
         let mut report = SyncReport::default();
         if dids.is_empty() {
             return Ok(report);
@@ -174,7 +195,7 @@ impl HandleSyncWorker {
         // the parallel-write benefit at this batch size.
         use futures::stream::{self, StreamExt};
         let dispatch_results: Vec<(String, anyhow::Result<Option<String>>)> = stream::iter(dids)
-            .map(|(did,)| async move {
+            .map(|did| async move {
                 let r = self.dispatch(&did).await;
                 (did, r)
             })
@@ -376,7 +397,11 @@ mod tests {
         .into_arc();
 
         let worker = worker_with(db, resolver);
-        let report = worker.run_once().await.unwrap();
+        // Drive the resolve half with our own DID instead of
+        // `run_once()`: the global scan is capped at BATCH_SIZE and
+        // this database is shared with a live indexer, so a freshly
+        // seeded DID is not guaranteed to make the batch.
+        let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
         assert!(report.resolved >= 2, "expected ≥2 resolved, got {report:?}");
         assert_eq!(report.failed, 0);
         assert_eq!(report.skipped, 0);
@@ -411,10 +436,14 @@ mod tests {
         .into_arc();
 
         let worker = worker_with(db, resolver);
-        let report = worker.run_once().await.unwrap();
+        // The SELECT is what filters an already-handled DID out, so
-        assert_eq!(report.resolved, 0);
+        // this one goes through the full `run_once()` — but scoped to
-        assert_eq!(report.failed, 0);
+        // the assertion that OUR did is untouched, not to global counts.
-        assert_eq!(report.skipped, 0); // DID was already filtered out by the SELECT
+        let candidates = worker.select_candidates().await.unwrap();
+        assert!(
+            !candidates.contains(&did),
+            "a DID with a handle must not be selected"
+        );
 
         let h = get_handle(&worker.db, &did).await;
         assert_eq!(h.as_deref(), Some("pre-existing.handle"));
@@ -456,8 +485,22 @@ mod tests {
             web_resolver: Arc::clone(&resolver),
             interval_secs: 999,
         };
-        let report = worker.run_once().await.unwrap();
+        // The cap lives in the SELECT, so that's what we assert on.
-        // Exactly BATCH_SIZE rows updated (one post per DID).
+        // Asserting `report.resolved == BATCH_SIZE` after a full
+        // `run_once()` only holds on a database where nothing else is
+        // waiting for a handle — against the shared dev DB with a live
+        // Jetstream indexer, other DIDs legitimately fill the batch.
+        let candidates = worker.select_candidates().await.unwrap();
+        assert!(
+            candidates.len() as i64 <= BATCH_SIZE,
+            "select must never exceed BATCH_SIZE, got {}",
+            candidates.len()
+        );
+
+        // And the resolve half must handle a full batch of our own
+        // DIDs: one row per DID, all of them updated.
+        let batch: Vec<String> = all_dids.iter().take(BATCH_SIZE as usize).cloned().collect();
+        let report = worker.resolve_batch(batch).await.unwrap();
         assert_eq!(
             report.resolved as i64,
             BATCH_SIZE,
@@ -465,7 +508,7 @@ mod tests {
         );
         assert_eq!(report.failed, 0);
 
-        // The remaining 5 DIDs must still have empty handles.
+        // The 5 DIDs we left out must still have empty handles.
         let remaining: i64 =
             sqlx::query_scalar("SELECT COUNT(*) FROM posts WHERE handle = '' AND did LIKE $1")
                 .bind(format!("{prefix}_%"))
@@ -528,12 +571,74 @@ mod tests {
             .await
             .unwrap();
 
-        let report = worker.run_once().await.unwrap();
+        // Scoped to our own DID: `run_once()`'s global batch would
+        // report whatever else the indexer left pending.
+        let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
         assert_eq!(report.resolved, 0, "must not touch already-handled rows");
         let h = get_handle(&worker.db, &did).await;
         assert_eq!(h.as_deref(), Some("from-ingest"));
     }
 
+    /// The documented PDS-first rule: the local PDS is asked before the
+    /// method dispatch, so a `did:key:` user hosted here resolves
+    /// without ever dialing plc.directory. This is the flip side of
+    /// `unknown_methods_are_skipped` — same DID method, opposite
+    /// outcome, and the difference is solely whether the PDS hosts it.
+    #[tokio::test]
+    async fn pds_resolves_did_key_before_method_dispatch() {
+        let Some(db) = try_test_db().await else {
+            eprintln!("appview DB unavailable; skipping");
+            return;
+        };
+        let did = format!("did:key:z{}", uuid::Uuid::new_v4().simple());
+        let _ = sqlx::query("DELETE FROM posts WHERE did = $1")
+            .bind(&did)
+            .execute(&db)
+            .await
+            .unwrap();
+        seed_post(&db, &did, "rk", "").await.unwrap();
+
+        // The PDS hosts this user; the outbound resolvers know nothing
+        // and must never be consulted.
+        let pds = StubResolver::new(HashMap::from([(
+            did.clone(),
+            Some("local-user.maarcadetweet.local".into()),
+        )]))
+        .into_arc();
+        let plc_log: Arc<Mutex<Vec<String>>> = Arc::new(Mutex::new(Vec::new()));
+        let plc = TrackingResolver::new(
+            HashMap::from([(did.clone(), Some("must-not-be-used".into()))]),
+            Arc::clone(&plc_log),
+        );
+        let plc_arc: Arc<dyn DidHandleResolver> = Arc::new(plc);
+
+        let worker = HandleSyncWorker {
+            db: db.clone(),
+            pds_resolver: pds,
+            plc_resolver: Arc::clone(&plc_arc),
+            web_resolver: plc_arc,
+            interval_secs: 999,
+        };
+        let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
+        assert_eq!(
+            report.resolved, 1,
+            "a did:key hosted by the local PDS must resolve, got {report:?}"
+        );
+        assert_eq!(
+            get_handle(&worker.db, &did).await.as_deref(),
+            Some("local-user.maarcadetweet.local")
+        );
+        assert!(
+            plc_log.lock().unwrap().is_empty(),
+            "the PDS answered, so no outbound resolver may be consulted"
+        );
+
+        let _ = sqlx::query("DELETE FROM posts WHERE did = $1")
+            .bind(&did)
+            .execute(&db)
+            .await;
+    }
+
     /// Dispatch test: a `did:web:` DID must be routed to the
     /// `web_resolver` (not the PLC one). Without this routing, every
     /// `did:web:` post would stay `@<did-prefix>…` forever.
@@ -564,14 +669,23 @@ mod tests {
         )]))
         .into_arc();
 
+        // The local PDS is consulted before the method dispatch (see the
+        // module docs), and it does NOT host this DID — a foreign
+        // `did:web:` is exactly the case where it answers "don't know".
+        // Wiring one of the other stubs in here instead would make the
+        // PDS claim a DID it doesn't have, and the test would be
+        // asserting against the documented PDS-first rule rather than
+        // against the method dispatch it's named for.
+        let pds = StubResolver::new(HashMap::new()).into_arc();
+
         let worker = HandleSyncWorker {
             db: db.clone(),
-            pds_resolver: Arc::clone(&plc),
+            pds_resolver: pds,
             plc_resolver: plc,
             web_resolver: web,
             interval_secs: 999,
         };
-        let report = worker.run_once().await.unwrap();
+        let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
         assert_eq!(
             report.resolved, 1,
             "did:web must resolve through the web resolver, got {report:?}"
@@ -623,14 +737,21 @@ mod tests {
         let plc_arc: Arc<dyn DidHandleResolver> = Arc::new(plc);
         let web_arc: Arc<dyn DidHandleResolver> = Arc::new(web);
 
+        // A DID the local PDS does not host — otherwise the PDS-first
+        // rule would (correctly) resolve it and this test would be
+        // measuring the wrong thing. The "local PDS *does* host it"
+        // case is covered by `pds_resolves_did_key_before_method_dispatch`.
+        let pds_arc: Arc<dyn DidHandleResolver> =
+            Arc::new(StubResolver::new(HashMap::new()));
+
         let worker = HandleSyncWorker {
             db: db.clone(),
-            pds_resolver: Arc::clone(&plc_arc),
+            pds_resolver: pds_arc,
             plc_resolver: plc_arc,
             web_resolver: web_arc,
             interval_secs: 999,
         };
-        let report = worker.run_once().await.unwrap();
+        let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
         assert_eq!(report.resolved, 0, "did:key must not resolve, got {report:?}");
         assert_eq!(
             report.failed, 0,

crates/appview/src/indexer.rs

@@ -348,6 +348,31 @@ pub async fn upsert_post(db: &PgPool, row: &mut PostRow) -> Result<()> {
     .bind(&row.avatar_cid)
     .execute(db)
     .await?;
+
+    // Reply notification. A post with a `parent_uri` is a reply, so the
+    // parent's author gets a "someone replied to you" row.
+    //
+    // `subject_uri` is the REPLY's own URI, not the parent's: the
+    // notification list hydrates `subject_uri`'s text, and what the
+    // recipient wants to read is what the replier wrote — they already
+    // know the content of their own post. It also makes the row a
+    // direct link target for "open this reply in the thread view".
+    //
+    // The dedupe index keys on the reply URI, so re-indexing (or an
+    // edit that re-runs the upsert) can't produce a second row.
+    if let Some(parent_uri) = row.parent_uri.as_deref() {
+        if let Some(recipient) = post_author_did(db, parent_uri).await? {
+            record_notification(
+                db,
+                &recipient,
+                &row.did,
+                NOTIF_REPLY,
+                Some(&row.uri),
+                row.created_at,
+            )
+            .await?;
+        }
+    }
     Ok(())
 }
 
@@ -414,6 +439,23 @@ pub async fn upsert_like(
         .bind(&post_uri)
         .execute(&mut *tx)
         .await?;
+
+        // Notify the post's author. Runs inside the same transaction as
+        // the counter bump so a crash can't leave a like counted but
+        // un-notified (or vice versa). `post_author_did` returns None
+        // for a post we haven't indexed — then there's nobody to
+        // notify and we quietly skip.
+        if let Some(recipient) = post_author_did(&mut *tx, &post_uri).await? {
+            record_notification(
+                &mut *tx,
+                &recipient,
+                did,
+                NOTIF_LIKE,
+                Some(&post_uri),
+                created_at,
+            )
+            .await?;
+        }
     }
     tx.commit().await?;
     Ok(())
@@ -489,6 +531,20 @@ pub async fn upsert_repost(
         .bind(&post_uri)
         .execute(&mut *tx)
         .await?;
+
+        // Same transactional notification write as the like path — see
+        // `upsert_like` for the rationale.
+        if let Some(recipient) = post_author_did(&mut *tx, &post_uri).await? {
+            record_notification(
+                &mut *tx,
+                &recipient,
+                did,
+                NOTIF_REPOST,
+                Some(&post_uri),
+                created_at,
+            )
+            .await?;
+        }
     }
     tx.commit().await?;
     Ok(())
@@ -517,6 +573,124 @@ pub async fn delete_repost(db: &PgPool, did: &str, rkey: &str) -> Result<()> {
     Ok(())
 }
 
+// -- notifications ---------------------------------------------------------
+
+/// The four notification kinds the AppView produces. Kept as `&str`
+/// constants rather than an enum because the value is a plain `TEXT`
+/// column guarded by a CHECK constraint (migration 0008) and every
+/// call site is a literal — an enum would only add a `to_string()`.
+pub const NOTIF_LIKE: &str = "like";
+pub const NOTIF_REPOST: &str = "repost";
+pub const NOTIF_FOLLOW: &str = "follow";
+pub const NOTIF_REPLY: &str = "reply";
+
+/// Should an interaction by `author_did` aimed at `recipient_did`
+/// produce a notification row?
+///
+/// Pure so it can be unit-tested without a database. Two rules:
+///
+///  1. **No self-interactions.** Liking your own post, reposting
+///     yourself, self-following or replying to yourself must stay
+///     silent — the user already knows they did it, and a "you liked
+///     your own post" row is pure noise.
+///  2. **No empty DIDs.** An empty recipient means we failed to resolve
+///     the target (e.g. a like against a post that isn't in our index),
+///     and an empty author means the event was malformed. Either way
+///     the row would be unattributable in the UI.
+///
+/// The same two rules are ALSO enforced in SQL inside
+/// [`record_notification`], so a caller that forgets this guard still
+/// can't write a bad row — this function exists to skip the round trip
+/// in the common self-interaction case and to make the rule testable.
+pub fn should_notify(recipient_did: &str, author_did: &str) -> bool {
+    !recipient_did.is_empty() && !author_did.is_empty() && recipient_did != author_did
+}
+
+/// Insert one notification row, if and only if it is warranted.
+///
+/// Returns `Ok(true)` when a row was actually written, `Ok(false)` when
+/// the write was skipped — either because the interaction failed
+/// [`should_notify`], because the recipient isn't a user this AppView
+/// serves, or because the same notification already exists.
+///
+/// **"Local user"**: the AppView deliberately has no `users` table —
+/// the PDS owns account state. The closest thing we have is "a DID this
+/// AppView knows about", i.e. one with a row in the `profiles` cache
+/// (written by the PDS profile push / the Jetstream `app.bsky.actor.profile`
+/// arm) or at least one indexed post. That is exactly the set of users
+/// a client could ever poll notifications for, so restricting writes to
+/// it keeps us from materialising a notification row for every like on
+/// the entire public firehose while never dropping one a local user
+/// would actually see.
+///
+/// **Idempotency**: the `ON CONFLICT` target is the expression index
+/// `notifications_dedupe_idx` from migration 0008, keyed on
+/// `(recipient_did, author_did, kind, COALESCE(subject_uri, ''))`. The
+/// `COALESCE` is load-bearing: a plain unique index would let two
+/// `follow` rows (whose `subject_uri` is NULL) coexist, because SQL
+/// NULLs never collide. Re-indexing the same Jetstream event — on a
+/// reconnect replay, or via the PDS `/internal/ingest-commit` push that
+/// races the firehose — is therefore a no-op.
+///
+/// The executor is generic so this can run either on the pool (the
+/// reply path) or inside the caller's transaction (the like / repost
+/// paths, where the notification must commit atomically with the
+/// counter bump).
+pub async fn record_notification<'e, E>(
+    exec: E,
+    recipient_did: &str,
+    author_did: &str,
+    kind: &str,
+    subject_uri: Option<&str>,
+    created_at: chrono::DateTime<chrono::Utc>,
+) -> Result<bool>
+where
+    E: sqlx::PgExecutor<'e>,
+{
+    if !should_notify(recipient_did, author_did) {
+        return Ok(false);
+    }
+    // One statement, so there's no TOCTOU window between "is the
+    // recipient local?" and "insert". Every parameter is explicitly
+    // cast because `INSERT ... SELECT $1, $2, ...` gives Postgres no
+    // column context to infer the placeholder types from.
+    let res = sqlx::query(
+        r#"INSERT INTO notifications
+              (recipient_did, author_did, kind, subject_uri, created_at)
+           SELECT $1::text, $2::text, $3::text, $4::text, $5::timestamptz
+            WHERE $1::text <> $2::text
+              AND $1::text <> ''
+              AND $2::text <> ''
+              AND (EXISTS (SELECT 1 FROM profiles WHERE did = $1::text)
+                OR EXISTS (SELECT 1 FROM posts    WHERE did = $1::text))
+           ON CONFLICT (recipient_did, author_did, kind, COALESCE(subject_uri, ''))
+           DO NOTHING"#,
+    )
+    .bind(recipient_did)
+    .bind(author_did)
+    .bind(kind)
+    .bind(subject_uri)
+    .bind(created_at)
+    .execute(exec)
+    .await?;
+    Ok(res.rows_affected() > 0)
+}
+
+/// Look up the author DID of an indexed post. `None` when the post
+/// isn't in our index — which is the normal case for a like/reply
+/// aimed at a post hosted somewhere we don't follow. The caller then
+/// simply skips the notification rather than guessing a recipient.
+async fn post_author_did<'e, E>(exec: E, uri: &str) -> Result<Option<String>>
+where
+    E: sqlx::PgExecutor<'e>,
+{
+    let did: Option<String> = sqlx::query_scalar("SELECT did FROM posts WHERE uri = $1")
+        .bind(uri)
+        .fetch_optional(exec)
+        .await?;
+    Ok(did)
+}
+
 // -- follows ---------------------------------------------------------------
 
 pub async fn upsert_follow(
@@ -540,6 +714,22 @@ pub async fn upsert_follow(
     .bind(created_at)
     .execute(db)
     .await?;
+
+    // Notify the followed user. `subject_uri` is NULL — a follow isn't
+    // about a post — which is exactly the case the dedupe index's
+    // `COALESCE(subject_uri, '')` exists for. Not wrapped in a
+    // transaction with the follow upsert: the follow row is the source
+    // of truth and a missed notification is recoverable noise, whereas
+    // taking a transaction here would serialise every follow write.
+    record_notification(
+        db,
+        subject_did,
+        follower_did,
+        NOTIF_FOLLOW,
+        None,
+        created_at,
+    )
+    .await?;
     Ok(())
 }
 
@@ -1181,6 +1371,373 @@ mod tests {
     }
 }
 
+#[cfg(test)]
+mod notification_tests {
+    use super::*;
+    use serde_json::json;
+
+    fn did(tag: &str) -> String {
+        format!("did:plc:notif_{}_{}", tag, uuid::Uuid::new_v4().simple())
+    }
+
+    /// Seed one post so `did` counts as a user this AppView knows
+    /// about (see [`record_notification`]'s "local user" note) and so
+    /// there's something to like / reply to.
+    ///
+    /// The `handle` is deliberately non-empty. `handle_sync`'s tests
+    /// assert exact counts over a *global* scan of empty-handle rows,
+    /// so a fixture that left the column blank would silently break
+    /// them whenever both suites share a database.
+    async fn seed_post(db: &PgPool, author: &str, rkey: &str) -> String {
+        let uri = format!("at://{author}/app.twi.post/{rkey}");
+        sqlx::query(
+            r#"INSERT INTO posts
+                 (uri, did, handle, rkey, collection, text, cid,
+                  parent_uri, root_uri, langs, created_at)
+               VALUES ($1,$2,'notif-fixture.test','x','app.twi.post','seed','bafy',
+                       NULL,NULL,NULL, now())
+               ON CONFLICT (uri) DO NOTHING"#,
+        )
+        .bind(&uri)
+        .bind(author)
+        .execute(db)
+        .await
+        .unwrap();
+        uri
+    }
+
+    async fn count_notifications(db: &PgPool, recipient: &str, kind: &str) -> i64 {
+        sqlx::query_scalar(
+            "SELECT COUNT(*)::BIGINT FROM notifications \
+              WHERE recipient_did = $1 AND kind = $2",
+        )
+        .bind(recipient)
+        .bind(kind)
+        .fetch_one(db)
+        .await
+        .unwrap()
+    }
+
+    async fn cleanup(db: &PgPool, dids: &[&str]) {
+        for d in dids {
+            let _ = sqlx::query(
+                "DELETE FROM notifications WHERE recipient_did = $1 OR author_did = $1",
+            )
+            .bind(d)
+            .execute(db)
+            .await;
+            let _ = sqlx::query("DELETE FROM likes WHERE did = $1")
+                .bind(d)
+                .execute(db)
+                .await;
+            let _ = sqlx::query("DELETE FROM reposts WHERE did = $1")
+                .bind(d)
+                .execute(db)
+                .await;
+            let _ = sqlx::query("DELETE FROM follows WHERE follower_did = $1 OR subject_did = $1")
+                .bind(d)
+                .execute(db)
+                .await;
+            let _ = sqlx::query("DELETE FROM posts WHERE did = $1")
+                .bind(d)
+                .execute(db)
+                .await;
+        }
+    }
+
+    #[test]
+    fn should_notify_rejects_self_and_empty() {
+        assert!(should_notify("did:plc:a", "did:plc:b"));
+        // Self-interaction: liking / replying to / following yourself.
+        assert!(!should_notify("did:plc:a", "did:plc:a"));
+        // Unresolvable ends of the edge.
+        assert!(!should_notify("", "did:plc:b"));
+        assert!(!should_notify("did:plc:a", ""));
+        assert!(!should_notify("", ""));
+        // Case matters — DIDs are compared verbatim, never folded.
+        assert!(should_notify("did:plc:A", "did:plc:a"));
+    }
+
+    /// A like by someone else must produce exactly one notification,
+    /// and re-indexing the same event (Jetstream replay racing the PDS
+    /// push) must not produce a second.
+    #[tokio::test]
+    async fn like_notifies_author_once() {
+        let Some(db) = try_test_db().await else {
+            eprintln!("appview DB unavailable; skipping");
+            return;
+        };
+        let author = did("author");
+        let liker = did("liker");
+        // The liker also needs to exist for nothing in particular —
+        // only the *recipient* is checked — but seeding both keeps the
+        // fixture symmetric with reality.
+        let post_uri = seed_post(&db, &author, "p1").await;
+        seed_post(&db, &liker, "p1").await;
+
+        let record = json!({
+            "subject": { "uri": post_uri, "cid": "bafysubject" },
+            "createdAt": "2026-07-01T12:00:00Z"
+        });
+        upsert_like(&db, &liker, "lrk1", Some("bafylike"), Some(&record))
+            .await
+            .unwrap();
+        assert_eq!(count_notifications(&db, &author, NOTIF_LIKE).await, 1);
+
+        // Replay the exact same event.
+        upsert_like(&db, &liker, "lrk1", Some("bafylike"), Some(&record))
+            .await
+            .unwrap();
+        assert_eq!(
+            count_notifications(&db, &author, NOTIF_LIKE).await,
+            1,
+            "replayed like must not duplicate the notification"
+        );
+
+        // Unlike + re-like under a NEW rkey. The like row is recreated
+        // but the notification tuple is unchanged, so the dedupe index
+        // suppresses it — see migration 0008's "Idempotency" note.
+        delete_like(&db, &liker, "lrk1").await.unwrap();
+        upsert_like(&db, &liker, "lrk2", Some("bafylike2"), Some(&record))
+            .await
+            .unwrap();
+        assert_eq!(
+            count_notifications(&db, &author, NOTIF_LIKE).await,
+            1,
+            "toggling a like must not be a notification-spam vector"
+        );
+
+        // The stored row must point at the liked post and name the
+        // liker as the author.
+        let row: (String, Option<String>) = sqlx::query_as(
+            "SELECT author_did, subject_uri FROM notifications \
+              WHERE recipient_did = $1 AND kind = $2",
+        )
+        .bind(&author)
+        .bind(NOTIF_LIKE)
+        .fetch_one(&db)
+        .await
+        .unwrap();
+        assert_eq!(row.0, liker);
+        assert_eq!(row.1.as_deref(), Some(post_uri.as_str()));
+        // Unread by default — that's what /api/notifications/count sees.
+        let unread: i64 = sqlx::query_scalar(
+            "SELECT COUNT(*)::BIGINT FROM notifications \
+              WHERE recipient_did = $1 AND read_at IS NULL",
+        )
+        .bind(&author)
+        .fetch_one(&db)
+        .await
+        .unwrap();
+        assert_eq!(unread, 1);
+
+        cleanup(&db, &[&author, &liker]).await;
+    }
+
+    /// Liking / reposting your own post is silent.
+    #[tokio::test]
+    async fn self_interaction_writes_no_notification() {
+        let Some(db) = try_test_db().await else {
+            eprintln!("appview DB unavailable; skipping");
+            return;
+        };
+        let author = did("selfie");
+        let post_uri = seed_post(&db, &author, "p1").await;
+        let record = json!({
+            "subject": { "uri": post_uri, "cid": "bafysubject" },
+            "createdAt": "2026-07-01T12:00:00Z"
+        });
+
+        upsert_like(&db, &author, "lrk1", None, Some(&record))
+            .await
+            .unwrap();
+        upsert_repost(&db, &author, "rrk1", None, Some(&record))
+            .await
+            .unwrap();
+        // Self-follow is legal in the protocol; it must stay silent too.
+        upsert_follow(&db, &author, &author, None).await.unwrap();
+
+        let total: i64 = sqlx::query_scalar(
+            "SELECT COUNT(*)::BIGINT FROM notifications WHERE recipient_did = $1",
+        )
+        .bind(&author)
+        .fetch_one(&db)
+        .await
+        .unwrap();
+        assert_eq!(total, 0, "self-interactions must not notify");
+
+        // The like/repost themselves still landed — the notification
+        // suppression must not swallow the interaction.
+        let likes: i64 = sqlx::query_scalar("SELECT COUNT(*)::BIGINT FROM likes WHERE did = $1")
+            .bind(&author)
+            .fetch_one(&db)
+            .await
+            .unwrap();
+        assert_eq!(likes, 1);
+
+        cleanup(&db, &[&author]).await;
+    }
+
+    /// A repost notifies, and a reply notifies the *parent's* author
+    /// with the reply's own URI as the subject.
+    #[tokio::test]
+    async fn repost_and_reply_notify() {
+        let Some(db) = try_test_db().await else {
+            eprintln!("appview DB unavailable; skipping");
+            return;
+        };
+        let author = did("parent");
+        let other = did("replier");
+        let parent_uri = seed_post(&db, &author, "p1").await;
+        seed_post(&db, &other, "p1").await;
+
+        let record = json!({
+            "subject": { "uri": parent_uri, "cid": "bafysubject" },
+            "createdAt": "2026-07-01T12:00:00Z"
+        });
+        upsert_repost(&db, &other, "rrk1", None, Some(&record))
+            .await
+            .unwrap();
+        assert_eq!(count_notifications(&db, &author, NOTIF_REPOST).await, 1);
+
+        // Now a reply from `other` to `author`'s post.
+        let reply_record = json!({
+            "text": "nice one",
+            "createdAt": "2026-07-01T12:05:00Z",
+            "reply": {
+                "parent": { "uri": parent_uri, "cid": "bafyparent" },
+                "root":   { "uri": parent_uri, "cid": "bafyparent" }
+            }
+        });
+        let mut row = PostRow::from_record(
+            &other,
+            "replykey",
+            "app.twi.post",
+            "bafyreply",
+            &reply_record,
+            None,
+        );
+        let reply_uri = row.uri.clone();
+        upsert_post(&db, &mut row).await.unwrap();
+
+        let subject: Option<String> = sqlx::query_scalar(
+            "SELECT subject_uri FROM notifications \
+              WHERE recipient_did = $1 AND kind = $2",
+        )
+        .bind(&author)
+        .bind(NOTIF_REPLY)
+        .fetch_one(&db)
+        .await
+        .unwrap();
+        assert_eq!(
+            subject.as_deref(),
+            Some(reply_uri.as_str()),
+            "a reply notification's subject is the REPLY, so the list can \
+             preview what was written"
+        );
+
+        // Re-indexing the reply must not duplicate.
+        upsert_post(&db, &mut row).await.unwrap();
+        assert_eq!(count_notifications(&db, &author, NOTIF_REPLY).await, 1);
+
+        cleanup(&db, &[&author, &other]).await;
+    }
+
+    /// A follow notifies the followed user with a NULL subject_uri —
+    /// the case the dedupe index's `COALESCE(subject_uri, '')` exists
+    /// for, since plain SQL NULLs never collide.
+    #[tokio::test]
+    async fn follow_notifies_subject_and_dedupes_on_null_subject() {
+        let Some(db) = try_test_db().await else {
+            eprintln!("appview DB unavailable; skipping");
+            return;
+        };
+        let subject = did("followee");
+        let follower = did("follower");
+        seed_post(&db, &subject, "p1").await;
+
+        let record = json!({ "subject": subject, "createdAt": "2026-01-01T00:00:00Z" });
+        upsert_follow(&db, &follower, &subject, Some(&record))
+            .await
+            .unwrap();
+        upsert_follow(&db, &follower, &subject, Some(&record))
+            .await
+            .unwrap();
+        assert_eq!(
+            count_notifications(&db, &subject, NOTIF_FOLLOW).await,
+            1,
+            "two NULL-subject follow rows must collide, not coexist"
+        );
+
+        let subject_uri: Option<String> = sqlx::query_scalar(
+            "SELECT subject_uri FROM notifications \
+              WHERE recipient_did = $1 AND kind = $2",
+        )
+        .bind(&subject)
+        .bind(NOTIF_FOLLOW)
+        .fetch_one(&db)
+        .await
+        .unwrap();
+        assert!(subject_uri.is_none(), "a follow is not about a post");
+
+        cleanup(&db, &[&subject, &follower]).await;
+    }
+
+    /// A recipient the AppView has never seen (no profile row, no
+    /// posts) gets nothing — this is what keeps us from materialising
+    /// a row for every like on the public firehose.
+    #[tokio::test]
+    async fn unknown_recipient_is_skipped() {
+        let Some(db) = try_test_db().await else {
+            eprintln!("appview DB unavailable; skipping");
+            return;
+        };
+        let stranger = did("stranger");
+        let author = did("author");
+
+        let wrote = record_notification(
+            &db,
+            &stranger,
+            &author,
+            NOTIF_FOLLOW,
+            None,
+            chrono::Utc::now(),
+        )
+        .await
+        .unwrap();
+        assert!(!wrote, "unknown recipient must not get a notification row");
+
+        // Give the recipient a post — now they're a user we serve.
+        seed_post(&db, &stranger, "p1").await;
+        let wrote = record_notification(
+            &db,
+            &stranger,
+            &author,
+            NOTIF_FOLLOW,
+            None,
+            chrono::Utc::now(),
+        )
+        .await
+        .unwrap();
+        assert!(wrote, "known recipient must get the row");
+
+        // And the second call is a no-op thanks to ON CONFLICT.
+        let wrote = record_notification(
+            &db,
+            &stranger,
+            &author,
+            NOTIF_FOLLOW,
+            None,
+            chrono::Utc::now(),
+        )
+        .await
+        .unwrap();
+        assert!(!wrote, "duplicate must report false, not error");
+
+        cleanup(&db, &[&stranger, &author]).await;
+    }
+}
+
 /// Backfill the `posts.handle` column for every row belonging to
 /// `did`. Used by the Jetstream `identity` handler when Jetstream
 /// tells us a DID's handle has changed — every existing post row

crates/appview/src/ingest.rs

@@ -15,8 +15,31 @@
 //! }
 //! ```
 //!
-//! In production this endpoint would be protected with mTLS and a token
+//! ## Who may call this
-//! minted by the PDS; for now it's open inside the cluster.
+//!
+//! This is the AppView's only write path, and it is not a browser
+//! endpoint: it is excluded from the CORS layer in
+//! [`crate::routes::router`], because an `Access-Control-Allow-Origin`
+//! header here would only ever help a web page forge index entries.
+//!
+//! Authentication is the shared secret `APPVIEW_INGEST_SECRET`,
+//! compared in constant time against the caller's `X-Ingest-Secret`
+//! header:
+//!
+//! - **set** → enforced. A missing or wrong header is `401
+//!   AuthenticationRequired`.
+//! - **unset** → anonymous writes are accepted, and the AppView shouts
+//!   about it once at startup (see
+//!   [`crate::auth::log_startup_posture`]). Refusing to start would
+//!   break every existing single-machine dev setup for a service that,
+//!   in that configuration, is bound to loopback anyway; accepting
+//!   silently is how an internet-facing deployment ends up letting
+//!   anyone forge posts, follows and notifications. So: keep working,
+//!   but never quietly.
+//!
+//! A future hardening step is mTLS or a PDS-minted token, at which
+//! point the shared secret becomes the fallback rather than the only
+//! line.
 
 use crate::indexer;
 use crate::state::AppState;
@@ -51,8 +74,13 @@ pub struct IngestCommitReq {
 }
 
 /// Authenticate internal ingest requests.
-/// - If `APPVIEW_INGEST_SECRET` env var is unset: dev mode, accept anything.
+///
-/// - If set: require `X-Ingest-Secret: <value>` header to match.
+/// - `APPVIEW_INGEST_SECRET` unset: accept anonymous writes (dev mode —
+///   the startup log warns, see the module docs for why this isn't a
+///   hard failure).
+/// - Set: require a matching `X-Ingest-Secret` header. The comparison
+///   is constant-time so a caller can't recover the secret byte by byte
+///   from response timings.
 pub fn check_ingest_secret(
     headers: &HeaderMap,
     configured: Option<&str>,

crates/appview/src/lib.rs

@@ -3,6 +3,7 @@
 //! tests under `tests/` import from here so they can build a worker
 //! against a stub resolver without booting the binary.
 
+pub mod auth;
 pub mod firehose;
 pub mod handle_sync;
 pub mod indexer;

crates/appview/src/main.rs

@@ -7,6 +7,7 @@ use tokio::sync::mpsc;
 use tracing::info;
 use tracing_subscriber::EnvFilter;
 
+mod auth;
 mod firehose;
 mod handle_sync;
 mod indexer;
@@ -18,6 +19,12 @@ use state::AppState;
 
 #[tokio::main]
 async fn main() -> Result<()> {
+    // Load `.env` from the working directory (and upwards) if present.
+    // Nothing else in the process reads it, so without this
+    // `cp .env.example .env && cargo run` fails with `missing env:
+    // PDS_HOST`. Real environment variables always win over the file.
+    let _ = dotenvy::dotenv();
+
     // Install a rustls crypto provider before any TLS connection. `ring`
     // is the only one we currently support; using `aws_lc_rs` would
     // require a non-default feature on rustls.
@@ -77,6 +84,33 @@ async fn main() -> Result<()> {
 
     let state = AppState::new(cfg.clone(), db.clone(), stats.clone());
 
+    // Announce every relaxed security switch before we serve anything.
+    auth::log_startup_posture(&cfg);
+
+    // Pre-load the PDS's published signing key so the first
+    // authenticated request doesn't pay for the round trip.
+    //
+    // Best effort on purpose: the AppView has always started
+    // independently of the PDS, and in a compose file the two race. A
+    // hard failure here would turn "the PDS booted two seconds later"
+    // into "the AppView is in a crash loop". If the fetch fails, the
+    // first authenticated request retries it — and answers `503
+    // AuthUnavailable` if the PDS is still unreachable. Never open.
+    if cfg.appview_auth_required {
+        match state.pds_keys.refresh().await {
+            Ok(_) => info!(
+                url = %state.pds_keys.did_doc_url(),
+                "loaded PDS signing key for token verification"
+            ),
+            Err(e) => tracing::warn!(
+                url = %state.pds_keys.did_doc_url(),
+                error = %e,
+                "could not load the PDS signing key at startup; will retry on the \
+                 first authenticated request (which fails with 503 until it works)"
+            ),
+        }
+    }
+
     // Back-fill the `handle` column on posts that the Jetstream
     // indexer inserted with an empty placeholder. The worker dispatches
     // by DID method: `did:plc:` → PLC directory, `did:web:` → a
@@ -96,12 +130,12 @@ async fn main() -> Result<()> {
     // inside docker compose) — `pds_public_url` may not be reachable
     // from inside the cluster when TLS / DNS is set up for outside
     // clients only.
-    let pds_base_url = cfg
+    //
-        .pds_internal_url
+    // `AppConfig::pds_base_url()` owns that fallback so the handle
-        .clone()
+    // resolver and the signing-key fetch in `auth.rs` can never end up
-        .unwrap_or_else(|| cfg.pds_public_url.clone());
+    // pointed at different PDS instances.
     let pds_resolver: Arc<dyn at_identity::DidHandleResolver> = Arc::new(
-        at_identity::pds_handle::PdsHandleResolver::new(pds_base_url),
+        at_identity::pds_handle::PdsHandleResolver::new(cfg.pds_base_url()),
     );
 
     let handle_sync = handle_sync::HandleSyncWorker {

crates/appview/src/routes/types.rs

@@ -199,6 +199,165 @@ pub struct SearchResponse {
     pub q: String,
 }
 
+// -- thread -----------------------------------------------------------------
+
+/// `GET /api/thread` response.
+///
+/// This is the *full* thread shape: the ancestor chain above the post
+/// and the direct replies below it. `/api/post/{uri}` keeps its own,
+/// narrower `{ post, thread: { parent, root } }` shape for backwards
+/// compatibility — both are built from the same
+/// `routes::load_thread_context` call, so they can never disagree
+/// about what the parent or root is.
+///
+/// `post` is `None` when the URI isn't in our index. In that case
+/// `parents` / `replies` are empty and the counters are omitted, so a
+/// client can render "post not found" from a single field check.
+#[derive(Debug, Serialize)]
+pub struct ThreadFullResponse {
+    pub post: Option<PostRow>,
+    /// Ancestor chain ordered **root first, immediate parent last**.
+    /// Empty for a top-level post, and truncated (from the top) when
+    /// the chain is longer than the walk limit or when an ancestor
+    /// isn't in our index — the client should treat a `parents[0]`
+    /// whose `parent_uri` is non-null as "chain continues above,
+    /// not loaded".
+    pub parents: Vec<PostRow>,
+    /// The thread root as named by the post's own `root_uri`. May be
+    /// the same row as `parents[0]`, and is `None` for a top-level
+    /// post (which is its own root).
+    pub root: Option<PostRow>,
+    /// Direct replies to `post`, oldest first. Only direct children —
+    /// the client re-requests `/api/thread` for a nested branch.
+    pub replies: Vec<PostRow>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub like_count: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub repost_count: Option<i64>,
+    /// Same semantics as on `/api/post/{uri}`: `None` means "no
+    /// viewer_did was supplied, state unknown" — not "not liked".
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub viewer_liked: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub viewer_reposted: Option<bool>,
+}
+
+// -- notifications ----------------------------------------------------------
+
+/// One hydrated row of `GET /api/notifications`.
+///
+/// The DB row only stores DIDs and a subject URI; the read query joins
+/// the `profiles` cache (falling back to the newest non-empty
+/// `posts.handle` for authors we've seen post but never had a profile
+/// record for) and the `posts` table so the client can render a full
+/// notification line without any follow-up fetch.
+///
+/// `read_at` is serialised even when `None` — unlike the optional
+/// fields around it — because "unread" is the state the client's badge
+/// keys off, and a *missing* key would be indistinguishable from a
+/// field the client forgot to read.
+#[derive(Debug, Clone, Serialize)]
+pub struct NotificationItem {
+    /// Row id. Also the tiebreaker inside the opaque cursor.
+    pub id: i64,
+    /// `"like"` | `"repost"` | `"follow"` | `"reply"`.
+    pub kind: String,
+    pub author_did: String,
+    /// Best known handle for the author, WITHOUT a leading `@` (the UI
+    /// renders `@{handle}`). Falls back to a truncated DID, and is
+    /// never null.
+    pub author_handle: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub author_display_name: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub author_avatar_cid: Option<String>,
+    /// The post this notification is about. `null` for `"follow"`. For
+    /// `"like"`/`"repost"` it's the recipient's own post; for
+    /// `"reply"` it's the reply itself.
+    pub subject_uri: Option<String>,
+    /// Text of `subject_uri`'s post. Omitted when the subject is not
+    /// (or no longer) in our index, and always for `"follow"`.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub subject_text: Option<String>,
+    /// The interaction's own `createdAt` from the AT record.
+    pub created_at: DateTime<Utc>,
+    /// When the AppView indexed it. This is the list's sort key, and
+    /// the value a client should echo back as `seenAt`.
+    pub indexed_at: DateTime<Utc>,
+    /// `null` while unread.
+    pub read_at: Option<DateTime<Utc>>,
+}
+
+impl<'r> FromRow<'r, sqlx::postgres::PgRow> for NotificationItem {
+    fn from_row(row: &'r sqlx::postgres::PgRow) -> sqlx::Result<Self> {
+        Ok(NotificationItem {
+            id: row.try_get("id")?,
+            kind: row.try_get("kind")?,
+            author_did: row.try_get("author_did")?,
+            author_handle: row.try_get("author_handle")?,
+            author_display_name: row.try_get("author_display_name")?,
+            author_avatar_cid: row.try_get("author_avatar_cid")?,
+            subject_uri: row.try_get("subject_uri")?,
+            subject_text: row.try_get("subject_text")?,
+            created_at: row.try_get("created_at")?,
+            indexed_at: row.try_get("indexed_at")?,
+            read_at: row.try_get("read_at")?,
+        })
+    }
+}
+
+/// `GET /api/notifications` response. `cursor` is `None` at the end of
+/// the list — same contract as [`TimelineResponse`].
+#[derive(Debug, Serialize)]
+pub struct NotificationsResponse {
+    pub notifications: Vec<NotificationItem>,
+    pub cursor: Option<String>,
+}
+
+/// `GET /api/notifications/count` response.
+#[derive(Debug, Serialize)]
+pub struct NotificationCountResponse {
+    /// Number of rows with `read_at IS NULL` for this DID.
+    pub count: i64,
+}
+
+/// `POST /api/notifications/seen` response.
+#[derive(Debug, Serialize)]
+pub struct NotificationSeenResponse {
+    pub ok: bool,
+    /// How many previously-unread rows this call flipped to read.
+    /// Zero is a normal, successful outcome (nothing was unread).
+    pub updated: i64,
+}
+
+// -- actor lists (followers / following) ------------------------------------
+
+/// A minimal profile card, as returned by `GET /api/followers` and
+/// `GET /api/following`.
+///
+/// Deliberately *not* [`ProfileResponse`]: those endpoints return a
+/// list, and shipping each entry's posts + counts would turn one page
+/// of 30 followers into 30 post queries. The client renders a row with
+/// avatar + name + handle and navigates to `/api/profile` on click.
+#[derive(Debug, Clone, Serialize)]
+pub struct ActorProfile {
+    pub did: String,
+    /// Without a leading `@`; falls back to a truncated DID and is
+    /// never null.
+    pub handle: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub display_name: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub avatar_cid: Option<String>,
+}
+
+/// `GET /api/followers` / `GET /api/following` response.
+#[derive(Debug, Serialize)]
+pub struct ActorListResponse {
+    pub profiles: Vec<ActorProfile>,
+    pub cursor: Option<String>,
+}
+
 // -- Langs newtype ----------------------------------------------------------
 
 /// A list of language tags. Always serialises as `Vec<String>`, never

crates/appview/src/state.rs

@@ -2,18 +2,30 @@ use at_shared::config::AppConfig;
 use sqlx::PgPool;
 use std::sync::Arc;
 
+use crate::auth::PdsKeys;
 use crate::firehose::Stats;
 
 #[derive(Clone)]
 pub struct AppState {
-    #[allow(dead_code)]
     pub cfg: AppConfig,
     pub db: PgPool,
     pub stats: Arc<Stats>,
+    /// Cache of the PDS's published signing key, used by the
+    /// [`crate::auth::AuthedDid`] extractor. Shared (`Arc`) so every
+    /// handler verifies against the same cached key and one HTTP
+    /// client, and so a key rotation picked up by one request is
+    /// immediately visible to the rest.
+    pub pds_keys: Arc<PdsKeys>,
 }
 
 impl AppState {
     pub fn new(cfg: AppConfig, db: PgPool, stats: Arc<Stats>) -> Self {
-        Self { cfg, db, stats }
+        let pds_keys = Arc::new(PdsKeys::from_config(&cfg));
+        Self {
+            cfg,
+            db,
+            stats,
+            pds_keys,
+        }
     }
 }

crates/appview/tests/api_integration.rs

@@ -7,6 +7,9 @@
 //! rather than panicking — so `cargo test --workspace` stays green in
 //! environments where the appview hasn't been started.
 
+mod common;
+
+use common::TestAuth;
 use serde_json::{json, Value};
 use std::time::Duration;
 
@@ -46,6 +49,36 @@ async fn db_reachable() -> bool {
     )
 }
 
+/// How this suite authenticates against `/api/timeline/home`, which is
+/// no longer public. `None` means the AppView enforces auth but the
+/// test process cannot mint a token (no `PDS_JWT_SECRET`), in which
+/// case the test skips like it does for a missing service.
+async fn auth_or_skip() -> Option<TestAuth> {
+    TestAuth::probe(&client().await, APPVIEW_URL).await
+}
+
+/// `GET /api/timeline/home` as `did`, with the bearer token attached
+/// when the instance requires one. The seeded DIDs are synthetic, so
+/// the token is minted from the PDS's own signing secret — see
+/// `tests/common/mod.rs`.
+async fn get_timeline(
+    c: &reqwest::Client,
+    auth: &TestAuth,
+    did: &str,
+    extra: &[(&str, &str)],
+) -> reqwest::Response {
+    let mut params: Vec<(&str, &str)> = vec![("did", did)];
+    params.extend_from_slice(extra);
+    auth.apply(
+        c.get(format!("{APPVIEW_URL}/api/timeline/home"))
+            .query(&params),
+        did,
+    )
+    .send()
+    .await
+    .unwrap()
+}
+
 async fn post_ingest(c: &reqwest::Client, body: Value) -> reqwest::Response {
     c.post(format!("{APPVIEW_URL}/internal/ingest-commit"))
         .json(&body)
@@ -120,6 +153,7 @@ async fn timeline_returns_seeded_posts() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let did = did_for_test("tl");
 
     // Seed 3 posts with distinct rkeys.
@@ -134,7 +168,11 @@ async fn timeline_returns_seeded_posts() {
                 "cid": "bafyreicid",
                 "record": {
                     "text": format!("seeded post #{i}"),
-                    "createdAt": "2026-07-01T12:00:00Z",
+                    // Strictly increasing so the ordering assertion
+                    // below has something to actually check: the rows
+                    // are inserted in this order, so `indexed_at` and
+                    // `created_at` agree for *our* posts.
+                    "createdAt": format!("2026-07-01T12:00:{:02}Z", i),
                 }
             }),
         )
@@ -147,12 +185,13 @@ async fn timeline_returns_seeded_posts() {
     // three rows in the first page.
     tokio::time::sleep(Duration::from_millis(50)).await;
 
-    let resp = c
+    // `limit=100`, not 10: this DID follows nobody, so the endpoint
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
+    // serves the cold-start *global* recent feed. On any database with
-        .query(&[("did", did.as_str()), ("limit", "10")])
+    // more than a handful of recent posts (i.e. every developer
-        .send()
+    // machine that has run this suite twice) the three rows we just
-        .await
+    // seeded fall outside a 10-row window and the assertions below
-        .unwrap();
+    // fail for reasons that have nothing to do with the timeline.
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "100")]).await;
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let posts = body["posts"].as_array().expect("posts is array");
@@ -174,15 +213,28 @@ async fn timeline_returns_seeded_posts() {
         .collect();
     assert!(our_uris.len() >= 3, "missing our seeded posts in {posts:?}");
 
-    // Posts must be sorted with `indexed_at DESC`. We can't see
+    // Posts come back `indexed_at DESC`, and we can't see `indexed_at`
-    // indexed_at directly in the response, but the URI order in
+    // in the response — but for the three rows WE just inserted,
-    // `app.twi.post/<rkey>` is rkey-random here, so we only assert
+    // insertion order == `indexed_at` order == `created_at` order, so
-    // `created_at` is non-increasing.
+    // their `created_at` values must be non-increasing.
+    //
+    // Two fixes over the original assertion:
+    //  - the wire field is `created_at`, not `createdAt` (the
+    //    `PostRow` wire type in `routes/types.rs` carries no
+    //    `rename_all = "camelCase"`), so `p["createdAt"]` was JSON
+    //    `null` and `.as_str().unwrap()` panicked on the first row;
+    //  - it ran over ALL posts, including other tests' fixtures from
+    //    the global cold-start feed, whose `created_at` values have
+    //    no relation to their `indexed_at` order. Restricting it to
+    //    our own DID is the only version of this claim that holds.
     let mut prev: Option<String> = None;
-    for p in posts {
+    for p in posts.iter().filter(|p| p["did"] == json!(did)) {
-        let ca = p["createdAt"].as_str().unwrap().to_string();
+        let ca = p["created_at"].as_str().unwrap().to_string();
-        if let Some(p) = prev.take() {
+        if let Some(prev) = prev.take() {
-            assert!(ca <= p, "createdAt must be non-increasing: {ca} <= {p}");
+            assert!(
+                ca <= prev,
+                "created_at must be non-increasing: {ca} <= {prev}"
+            );
         }
         prev = Some(ca);
     }
@@ -199,6 +251,7 @@ async fn timeline_paginates_with_cursor() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let did = did_for_test("pg");
 
     // Seed 50 posts.
@@ -223,28 +276,14 @@ async fn timeline_paginates_with_cursor() {
     tokio::time::sleep(Duration::from_millis(100)).await;
 
     // Page 1: limit=20.
-    let resp = c
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "20")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", did.as_str()), ("limit", "20")])
-        .send()
-        .await
-        .unwrap();
     let body: Value = resp.json().await.unwrap();
     let page1 = body["posts"].as_array().unwrap().clone();
     let cursor1 = body["cursor"].as_str().expect("page1 cursor");
     assert_eq!(page1.len(), 20, "page1 should be exactly 20");
 
     // Page 2: with cursor.
-    let resp = c
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "20"), ("cursor", cursor1)]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[
-            ("did", did.as_str()),
-            ("limit", "20"),
-            ("cursor", cursor1),
-        ])
-        .send()
-        .await
-        .unwrap();
     let body: Value = resp.json().await.unwrap();
     let page2 = body["posts"].as_array().unwrap().clone();
     assert_eq!(page2.len(), 20, "page2 should be exactly 20");
@@ -262,16 +301,7 @@ async fn timeline_paginates_with_cursor() {
 
     // Page 3: tail — fewer than 20 expected, cursor=null.
     let cursor2 = body["cursor"].as_str().expect("page2 cursor");
-    let resp = c
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "20"), ("cursor", cursor2)]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[
-            ("did", did.as_str()),
-            ("limit", "20"),
-            ("cursor", cursor2),
-        ])
-        .send()
-        .await
-        .unwrap();
     let body: Value = resp.json().await.unwrap();
     let page3 = body["posts"].as_array().unwrap().clone();
     assert!(page3.len() <= 20, "page3 should be <= 20");
@@ -354,16 +384,24 @@ async fn profile_returns_posts_for_handle() {
         .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
 
-    // 404 for an unknown handle.
+    // An unknown handle is NOT a 404. `resolve_profile` deliberately
+    // synthesises an empty profile (empty `did`, zero counts, no
+    // posts) so the UI renders an empty profile page instead of an
+    // error toast — see the comment on the `let Some(target_did)`
+    // else-branch in `routes.rs`. This assertion used to expect 404
+    // and contradicted the endpoint it was testing.
+    let unknown = format!("nobody_{}", uuid::Uuid::new_v4().simple());
     let resp = c
-        .get(format!(
+        .get(format!("{APPVIEW_URL}/api/profile/{unknown}"))
-            "{APPVIEW_URL}/api/profile/nobody_{}",
-            uuid::Uuid::new_v4().simple()
-        ))
         .send()
         .await
         .unwrap();
-    assert_eq!(resp.status().as_u16(), 404);
+    assert_eq!(resp.status().as_u16(), 200);
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(body["did"], json!(""));
+    assert_eq!(body["handle"], json!(unknown));
+    assert!(body["posts"].as_array().unwrap().is_empty());
+    assert_eq!(body["post_count"], json!(0));
 
     // /api/profile?did=... must work too.
     let resp = c
@@ -453,6 +491,7 @@ async fn timeline_filters_to_followees() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let url = std::env::var("DATABASE_URL_APPVIEW").unwrap();
     let pool = sqlx::PgPool::connect(&url).await.unwrap();
 
@@ -472,12 +511,7 @@ async fn timeline_filters_to_followees() {
 
     tokio::time::sleep(Duration::from_millis(100)).await;
 
-    let resp = c
+    let resp = get_timeline(&c, &auth, &alice, &[("limit", "100")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", alice.as_str()), ("limit", "100")])
-        .send()
-        .await
-        .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let posts = body["posts"].as_array().expect("posts is array");
@@ -524,18 +558,14 @@ async fn timeline_includes_own_posts() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let alice = did_for_test("alone");
 
     // Alice posts without seeding any follows.
     seed_posts(&c, &alice, &["alice's first post", "alice's second post"]).await;
     tokio::time::sleep(Duration::from_millis(100)).await;
 
-    let resp = c
+    let resp = get_timeline(&c, &auth, &alice, &[("limit", "100")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", alice.as_str()), ("limit", "100")])
-        .send()
-        .await
-        .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let posts = body["posts"].as_array().expect("posts is array");
@@ -574,6 +604,7 @@ async fn timeline_caps_followee_list() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let url = std::env::var("DATABASE_URL_APPVIEW").unwrap();
     let pool = sqlx::PgPool::connect(&url).await.unwrap();
 
@@ -593,12 +624,7 @@ async fn timeline_caps_followee_list() {
     seed_posts(&c, &alice, &["poweruser post"]).await;
     tokio::time::sleep(Duration::from_millis(100)).await;
 
-    let resp = c
+    let resp = get_timeline(&c, &auth, &alice, &[("limit", "50")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", alice.as_str()), ("limit", "50")])
-        .send()
-        .await
-        .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let posts = body["posts"].as_array().expect("posts is array");

crates/appview/tests/auth_integration.rs

@@ -0,0 +1,311 @@
+//! End-to-end tests for AppView authentication.
+//!
+//! Unlike the other suites in this directory these use a **real**
+//! token: the test creates an account on the running PDS
+//! (`com.atproto.server.createAccount`, the same call the desktop
+//! client makes at signup) and presents the access JWT it gets back to
+//! the AppView. That is the whole point — it exercises the actual key
+//! distribution path (PDS signs → publishes its public key at
+//! `/.well-known/did.json` → AppView fetches and verifies), which a
+//! self-minted token would bypass.
+//!
+//! Fail-open like the rest of the suites: if the PDS or the AppView
+//! isn't running, or the AppView runs with `APPVIEW_AUTH_REQUIRED=false`,
+//! the test prints a notice and returns successfully.
+
+use serde_json::{json, Value};
+use std::time::Duration;
+
+const PDS_URL: &str = "http://127.0.0.1:2583";
+
+fn appview_url() -> String {
+    std::env::var("APPVIEW_TEST_URL").unwrap_or_else(|_| "http://127.0.0.1:2584".to_string())
+}
+
+/// 30 s, not the 5 s the sibling suites use.
+///
+/// The authenticated happy path for `/api/timeline/home` runs the
+/// cold-start query (a brand-new account follows nobody, so the handler
+/// falls back to the global recent feed). On a developer machine whose
+/// AppView has been indexing the public firehose for a while that scan
+/// takes seconds — a timeout there would look like an auth failure and
+/// is nothing of the sort.
+fn client() -> reqwest::Client {
+    reqwest::Client::builder()
+        .timeout(Duration::from_secs(30))
+        .build()
+        .unwrap()
+}
+
+async fn up(c: &reqwest::Client, base: &str) -> bool {
+    for _ in 0..20 {
+        if let Ok(r) = c.get(format!("{base}/healthz")).send().await {
+            if r.status().is_success() {
+                return true;
+            }
+        }
+        tokio::time::sleep(Duration::from_millis(250)).await;
+    }
+    false
+}
+
+/// A freshly created PDS account.
+struct Account {
+    did: String,
+    access_jwt: String,
+    refresh_jwt: String,
+}
+
+/// Guard for every test here: both services up **and** the AppView
+/// actually enforcing auth. Returns the client plus a new account.
+async fn ready() -> Option<(reqwest::Client, Account)> {
+    let c = client();
+    if !up(&c, &appview_url()).await {
+        eprintln!("appview not running, skipping");
+        return None;
+    }
+    if !up(&c, PDS_URL).await {
+        eprintln!("pds not running, skipping");
+        return None;
+    }
+    // Probe: does this instance enforce auth? An operator running with
+    // `APPVIEW_AUTH_REQUIRED=false` (the mode the other suites use)
+    // would otherwise see every assertion here fail for the one reason
+    // that isn't a bug.
+    let probe = c
+        .get(format!("{}/api/notifications/count", appview_url()))
+        .query(&[("did", "did:plc:auth_probe")])
+        .send()
+        .await
+        .ok()?;
+    if probe.status().as_u16() != 401 {
+        eprintln!(
+            "appview does not enforce auth (probe returned {}), skipping",
+            probe.status()
+        );
+        return None;
+    }
+    let acc = create_account(&c).await?;
+    Some((c, acc))
+}
+
+async fn create_account(c: &reqwest::Client) -> Option<Account> {
+    let handle = format!("auth_{}.maarcadetweet.local", uuid::Uuid::new_v4().simple());
+    let r: Value = c
+        .post(format!("{PDS_URL}/xrpc/com.atproto.server.createAccount"))
+        .json(&json!({ "handle": handle, "password": "hunter2hunter2" }))
+        .send()
+        .await
+        .ok()?
+        .json()
+        .await
+        .ok()?;
+    Some(Account {
+        did: r["did"].as_str()?.to_string(),
+        access_jwt: r["access_jwt"].as_str()?.to_string(),
+        refresh_jwt: r["refresh_jwt"].as_str()?.to_string(),
+    })
+}
+
+/// `GET /api/notifications?did=…` with an optional bearer token.
+async fn get_notifications(
+    c: &reqwest::Client,
+    did: &str,
+    token: Option<&str>,
+) -> reqwest::Response {
+    let mut rb = c
+        .get(format!("{}/api/notifications", appview_url()))
+        .query(&[("did", did)]);
+    if let Some(t) = token {
+        rb = rb.bearer_auth(t);
+    }
+    rb.send().await.unwrap()
+}
+
+/// Assert the AppView's standard error envelope: the status, and the
+/// `error` code the desktop client branches on.
+async fn assert_error(r: reqwest::Response, status: u16, code: &str) {
+    let got = r.status().as_u16();
+    let body: Value = r.json().await.unwrap();
+    assert_eq!(got, status, "unexpected status; body = {body}");
+    assert_eq!(body["error"], json!(code), "unexpected error code: {body}");
+    assert!(
+        body["message"].is_string(),
+        "error body must carry a message: {body}"
+    );
+}
+
+#[tokio::test]
+async fn own_token_reads_own_notifications() {
+    let Some((c, acc)) = ready().await else { return };
+    let r = get_notifications(&c, &acc.did, Some(&acc.access_jwt)).await;
+    assert_eq!(r.status().as_u16(), 200);
+    let body: Value = r.json().await.unwrap();
+    // A brand-new account has no notifications, but the shape must be
+    // the normal list response, not an error.
+    assert!(body["notifications"].is_array(), "body = {body}");
+}
+
+#[tokio::test]
+async fn no_token_is_401_auth_missing() {
+    let Some((c, acc)) = ready().await else { return };
+    let r = get_notifications(&c, &acc.did, None).await;
+    assert_error(r, 401, "AuthMissing").await;
+}
+
+#[tokio::test]
+async fn foreign_did_is_403() {
+    let Some((c, acc)) = ready().await else { return };
+    // A valid token, but asking about somebody else's inbox. This is
+    // the case the endpoint used to answer with a 200.
+    let r = get_notifications(&c, "did:plc:somebodyelse", Some(&acc.access_jwt)).await;
+    assert_error(r, 403, "Forbidden").await;
+}
+
+#[tokio::test]
+async fn garbage_token_is_401_token_invalid() {
+    let Some((c, acc)) = ready().await else { return };
+    let r = get_notifications(&c, &acc.did, Some("not.a.jwt")).await;
+    assert_error(r, 401, "TokenInvalid").await;
+}
+
+#[tokio::test]
+async fn refresh_token_is_not_accepted() {
+    let Some((c, acc)) = ready().await else { return };
+    // Signed by the same key and valid for 90 days — only the `scope`
+    // claim separates it from a session credential.
+    let r = get_notifications(&c, &acc.did, Some(&acc.refresh_jwt)).await;
+    assert_error(r, 401, "TokenInvalid").await;
+}
+
+#[tokio::test]
+async fn seen_write_requires_matching_token() {
+    let Some((c, acc)) = ready().await else { return };
+    let url = format!("{}/api/notifications/seen", appview_url());
+
+    // Somebody else's unread badge: 403, nothing written.
+    let r = c
+        .post(&url)
+        .bearer_auth(&acc.access_jwt)
+        .json(&json!({ "did": "did:plc:somebodyelse" }))
+        .send()
+        .await
+        .unwrap();
+    assert_error(r, 403, "Forbidden").await;
+
+    // No credential at all: 401.
+    let r = c
+        .post(&url)
+        .json(&json!({ "did": &acc.did }))
+        .send()
+        .await
+        .unwrap();
+    assert_error(r, 401, "AuthMissing").await;
+
+    // Own inbox: allowed (zero rows updated — the account is new).
+    let r = c
+        .post(&url)
+        .bearer_auth(&acc.access_jwt)
+        .json(&json!({ "did": &acc.did }))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(r.status().as_u16(), 200);
+    let body: Value = r.json().await.unwrap();
+    assert_eq!(body["ok"], json!(true));
+}
+
+#[tokio::test]
+async fn timeline_home_is_authenticated() {
+    let Some((c, acc)) = ready().await else { return };
+    let base = appview_url();
+
+    let r = c
+        .get(format!("{base}/api/timeline/home"))
+        .query(&[("did", acc.did.as_str())])
+        .send()
+        .await
+        .unwrap();
+    assert_error(r, 401, "AuthMissing").await;
+
+    let r = c
+        .get(format!("{base}/api/timeline/home"))
+        .query(&[("did", "did:plc:somebodyelse")])
+        .bearer_auth(&acc.access_jwt)
+        .send()
+        .await
+        .unwrap();
+    assert_error(r, 403, "Forbidden").await;
+
+    let r = c
+        .get(format!("{base}/api/timeline/home"))
+        .query(&[("did", acc.did.as_str())])
+        .bearer_auth(&acc.access_jwt)
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(r.status().as_u16(), 200);
+}
+
+#[tokio::test]
+async fn public_endpoints_stay_public() {
+    let Some((c, acc)) = ready().await else { return };
+    let base = appview_url();
+
+    // Profiles, search, follower lists and the health probe are public
+    // records in AT Proto. Putting them behind auth would be a
+    // behaviour change no protocol rule asks for — assert they still
+    // answer without a token.
+    for (path, params) in [
+        ("/api/profile", vec![("did", acc.did.as_str())]),
+        ("/api/search", vec![("q", "hello")]),
+        ("/api/followers", vec![("did", acc.did.as_str())]),
+        ("/api/following", vec![("did", acc.did.as_str())]),
+        ("/healthz", vec![]),
+    ] {
+        let r = c
+            .get(format!("{base}{path}"))
+            .query(&params)
+            .send()
+            .await
+            .unwrap();
+        assert_eq!(
+            r.status().as_u16(),
+            200,
+            "{path} must remain public, got {}",
+            r.status()
+        );
+    }
+}
+
+/// The AppView can only verify anything because the PDS publishes its
+/// public key. If this document ever stops carrying a usable key, every
+/// authenticated request degrades to `503 AuthUnavailable` — so assert
+/// the shape the AppView parses.
+#[tokio::test]
+async fn pds_publishes_a_usable_signing_key() {
+    let c = client();
+    if !up(&c, PDS_URL).await {
+        eprintln!("pds not running, skipping");
+        return;
+    }
+    let doc: Value = c
+        .get(format!("{PDS_URL}/.well-known/did.json"))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    let id = doc["id"].as_str().expect("did document needs an id");
+    assert!(id.starts_with("did:web:"), "id = {id}");
+    let vm = &doc["verificationMethod"][0];
+    assert_eq!(vm["type"], json!("Multikey"));
+    assert_eq!(vm["controller"], json!(id));
+    let key = vm["publicKeyMultibase"]
+        .as_str()
+        .expect("verificationMethod needs publicKeyMultibase");
+    // base58-btc multibase: the `z` prefix is what the AppView's
+    // decoder expects.
+    assert!(key.starts_with('z'), "key = {key}");
+}

crates/appview/tests/common/mod.rs

@@ -0,0 +1,167 @@
+//! Shared test support for the AppView integration suites.
+//!
+//! ## Why the suites need this
+//!
+//! `/api/notifications*` and `/api/timeline/home` require a
+//! PDS-issued access token whose `sub` equals the `did` in the request.
+//! The suites, however, seed synthetic DIDs (`did:plc:ntf_…`) through
+//! `/internal/ingest-commit` — accounts the PDS has never heard of, so
+//! there is no `createSession` that would hand out a token for them.
+//!
+//! The way out is that a token is just an ES256 JWT signed with the
+//! server key derived from `PDS_JWT_SECRET`. A test that can read that
+//! secret (from the process environment, or from the repo `.env` the
+//! dev stack itself was started with) can mint a token for any DID it
+//! likes — the same thing `pds-server/src/jwt_issuer.rs` does.
+//!
+//! ## Fail-open, like the rest of the suites
+//!
+//! [`TestAuth::probe`] asks the running AppView whether it enforces
+//! auth at all:
+//!
+//! - not enforcing (`APPVIEW_AUTH_REQUIRED=false`) → no header needed;
+//! - enforcing and we have the secret → mint per-DID tokens;
+//! - enforcing and we don't → `None`, and the caller skips, exactly as
+//!   it already skips when the service or the database is down.
+
+#![allow(dead_code)]
+
+use at_crypto::ecdsa::P256Keypair;
+use at_crypto::jwt::{issue_jwt, JwtClaims};
+
+/// Audience the PDS stamps into access tokens. Not validated by
+/// `verify_jwt` today (`validate_aud = false`), but minting a token
+/// that differs from the real thing would make this helper a poor
+/// stand-in for the client.
+const APPVIEW_AUD: &str = "did:web:appview.maarcadetweet.local";
+
+/// The scope the AppView insists on. A token with any other scope —
+/// `com.atproto.refresh`, say — is rejected with `TokenInvalid`.
+pub const ACCESS_SCOPE: &str = "com.atproto.access";
+
+/// How the suite should authenticate against the AppView under test.
+///
+/// `Clone` because a test that pages through results in a closure has
+/// to hand each iteration its own copy, exactly like the client and the
+/// base URL next to it.
+#[derive(Clone)]
+pub enum TestAuth {
+    /// `APPVIEW_AUTH_REQUIRED=false`: send no `Authorization` header.
+    Disabled,
+    /// Auth is enforced; mint tokens with this hex secret.
+    Secret(String),
+}
+
+impl TestAuth {
+    /// Decide how (or whether) this suite can talk to the AppView.
+    ///
+    /// Returns `None` when the AppView enforces auth but no
+    /// `PDS_JWT_SECRET` is reachable — the caller should print a notice
+    /// and return, keeping `cargo test --workspace` green on a machine
+    /// without the dev stack's environment.
+    pub async fn probe(c: &reqwest::Client, base_url: &str) -> Option<Self> {
+        // An unauthenticated probe against a private endpoint. We only
+        // look at the status: 401 means the extractor is active. A DID
+        // that doesn't exist is fine — the auth check runs first.
+        let status = c
+            .get(format!("{base_url}/api/notifications/count"))
+            .query(&[("did", "did:plc:auth_probe")])
+            .send()
+            .await
+            .ok()?
+            .status()
+            .as_u16();
+        if status != 401 && status != 503 {
+            return Some(TestAuth::Disabled);
+        }
+        match pds_jwt_secret() {
+            Some(secret) => Some(TestAuth::Secret(secret)),
+            None => {
+                eprintln!(
+                    "appview enforces auth (probe returned {status}) but PDS_JWT_SECRET \
+                     is not set and no .env was found — skipping"
+                );
+                None
+            }
+        }
+    }
+
+    /// Attach an `Authorization: Bearer` header for `did`, if needed.
+    pub fn apply(&self, rb: reqwest::RequestBuilder, did: &str) -> reqwest::RequestBuilder {
+        match self {
+            TestAuth::Disabled => rb,
+            TestAuth::Secret(secret) => match mint_access_jwt(secret, did, ACCESS_SCOPE, 3600) {
+                Some(token) => rb.bearer_auth(token),
+                None => rb,
+            },
+        }
+    }
+
+    /// A token for `did` — for tests that want to send a *wrong* one on
+    /// purpose. `None` when auth is disabled, in which case the test
+    /// that needs it should skip.
+    pub fn token_for(&self, did: &str) -> Option<String> {
+        match self {
+            TestAuth::Disabled => None,
+            TestAuth::Secret(secret) => mint_access_jwt(secret, did, ACCESS_SCOPE, 3600),
+        }
+    }
+}
+
+/// `PDS_JWT_SECRET` from the environment, falling back to the repo
+/// `.env` — the same file the running dev stack loaded at startup, so
+/// the minted tokens verify against the key the PDS actually publishes.
+pub fn pds_jwt_secret() -> Option<String> {
+    if let Ok(v) = std::env::var("PDS_JWT_SECRET") {
+        if !v.trim().is_empty() {
+            return Some(v);
+        }
+    }
+    // `dotenvy::dotenv` walks up from the current directory, which for
+    // a test binary is the crate root — so this finds the workspace
+    // `.env` two levels up. It never overrides a real env var.
+    let _ = dotenvy::dotenv();
+    std::env::var("PDS_JWT_SECRET")
+        .ok()
+        .filter(|v| !v.trim().is_empty())
+}
+
+/// Mint an access JWT for `did`, signed with the PDS's server key.
+///
+/// Mirrors `pds-server/src/jwt_issuer.rs`: the P-256 secret scalar is
+/// the **first 32 bytes** of `PDS_JWT_SECRET` (the config allows a
+/// longer secret), i.e. the first 64 hex characters.
+///
+/// `ttl_secs` may be negative to build a deliberately expired token.
+pub fn mint_access_jwt(
+    secret_hex: &str,
+    did: &str,
+    scope: &str,
+    ttl_secs: i64,
+) -> Option<String> {
+    let hex = secret_hex.trim().trim_start_matches("0x");
+    if hex.len() < 64 || !hex.chars().all(|c| c.is_ascii_hexdigit()) {
+        eprintln!("PDS_JWT_SECRET is not ≥32 bytes of hex; cannot mint a test token");
+        return None;
+    }
+    let kp = P256Keypair {
+        secret_hex: hex[..64].to_string(),
+        // Only the signing half is used by `issue_jwt`; the verifier
+        // fetches the public key from the PDS's DID document.
+        public_multibase: String::new(),
+    };
+    let now = chrono::Utc::now().timestamp();
+    issue_jwt(
+        &kp,
+        &JwtClaims {
+            iss: "did:web:test".into(),
+            sub: did.to_string(),
+            aud: APPVIEW_AUD.into(),
+            iat: now - 1,
+            exp: now + ttl_secs,
+            jti: None,
+            scope: Some(scope.to_string()),
+        },
+    )
+    .ok()
+}

crates/appview/tests/embeds_integration.rs

@@ -15,6 +15,9 @@
 //! and returns rather than panicking. The point of the tests is to
 //! catch regressions in CI where the service IS up.
 
+mod common;
+
+use common::TestAuth;
 use serde_json::{json, Value};
 use std::time::Duration;
 
@@ -50,6 +53,32 @@ async fn db_reachable() -> bool {
     )
 }
 
+/// `/api/timeline/home` requires a token whose `sub` is the requested
+/// DID. The DIDs here are synthetic, so the token is minted from the
+/// PDS signing secret — see `tests/common/mod.rs`. `None` → skip.
+async fn auth_or_skip() -> Option<TestAuth> {
+    TestAuth::probe(&client().await, APPVIEW_URL).await
+}
+
+/// `GET /api/timeline/home` as `did`, authenticated when required.
+async fn get_timeline(
+    c: &reqwest::Client,
+    auth: &TestAuth,
+    did: &str,
+    extra: &[(&str, &str)],
+) -> reqwest::Response {
+    let mut params: Vec<(&str, &str)> = vec![("did", did)];
+    params.extend_from_slice(extra);
+    auth.apply(
+        c.get(format!("{APPVIEW_URL}/api/timeline/home"))
+            .query(&params),
+        did,
+    )
+    .send()
+    .await
+    .unwrap()
+}
+
 async fn post_ingest(c: &reqwest::Client, body: Value) -> reqwest::Response {
     c.post(format!("{APPVIEW_URL}/internal/ingest-commit"))
         .json(&body)
@@ -125,6 +154,7 @@ async fn timeline_includes_embed() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let did = did_for_test("img");
     let uri = seed_post(
         &c,
@@ -160,12 +190,7 @@ async fn timeline_includes_embed() {
     )
     .await;
 
-    let resp = c
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "10")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", did.as_str()), ("limit", "10")])
-        .send()
-        .await
-        .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let posts = body["posts"].as_array().unwrap();
@@ -199,6 +224,7 @@ async fn timeline_includes_external_embed() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let did = did_for_test("ext");
     let uri = seed_post(
         &c,
@@ -222,12 +248,7 @@ async fn timeline_includes_external_embed() {
     )
     .await;
 
-    let resp = c
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "10")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", did.as_str()), ("limit", "10")])
-        .send()
-        .await
-        .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let posts = body["posts"].as_array().unwrap();
@@ -241,12 +262,7 @@ async fn timeline_includes_external_embed() {
             break;
         }
         tokio::time::sleep(Duration::from_millis(50)).await;
-        let resp = c
+        let resp = get_timeline(&c, &auth, &did, &[("limit", "10")]).await;
-            .get(format!("{APPVIEW_URL}/api/timeline/home"))
-            .query(&[("did", did.as_str()), ("limit", "10")])
-            .send()
-            .await
-            .unwrap();
         let body: Value = resp.json().await.unwrap();
         our = body["posts"]
             .as_array()
@@ -410,6 +426,7 @@ async fn timeline_post_without_embed_has_null_embed() {
         return;
     }
     let c = client().await;
+    let Some(auth) = auth_or_skip().await else { return };
     let did = did_for_test("plain");
     let uri = seed_post(
         &c,
@@ -421,12 +438,7 @@ async fn timeline_post_without_embed_has_null_embed() {
     )
     .await;
 
-    let resp = c
+    let resp = get_timeline(&c, &auth, &did, &[("limit", "10")]).await;
-        .get(format!("{APPVIEW_URL}/api/timeline/home"))
-        .query(&[("did", did.as_str()), ("limit", "10")])
-        .send()
-        .await
-        .unwrap();
     assert_eq!(resp.status().as_u16(), 200);
     let body: Value = resp.json().await.unwrap();
     let our = body["posts"]

crates/appview/tests/handle_sync_integration.rs

@@ -175,8 +175,13 @@ async fn sync_resolves_known_did() {
     seed_post(&db, &did, "rkb", "", "second").await.unwrap();
     assert_eq!(count_empty_handle_for(&db, &did).await.unwrap(), 2);
 
+    // Drive the resolve half with our own DID. `run_once()` scans
+    // globally, ordered by DID and capped at BATCH_SIZE, so on a
+    // database that a live indexer keeps topping up, a freshly seeded
+    // DID isn't guaranteed to make the batch — the assertions below
+    // would then be measuring someone else's rows.
     let worker = worker_with(db.clone(), stub.clone());
-    let report: SyncReport = worker.run_once().await.unwrap();
+    let report: SyncReport = worker.resolve_batch(vec![did.clone()]).await.unwrap();
     assert_eq!(report.resolved, 2, "{report:?}");
     assert_eq!(report.failed, 0);
     assert_eq!(report.skipped, 0);
@@ -224,9 +229,16 @@ async fn sync_skips_already_resolved() {
     .into_arc();
 
     let worker = worker_with(db.clone(), stub.clone());
-    let report = worker.run_once().await.unwrap();
+    // This test is about the SELECT: a DID whose rows already carry a
-    assert_eq!(report.resolved, 0, "{report:?}");
+    // handle must never reach a resolver in the first place. So assert
-    assert_eq!(report.failed, 0);
+    // on `select_candidates()` rather than forcing the DID through
+    // `resolve_batch` — that would consult the resolver by definition
+    // and defeat the `query_count == 0` check below.
+    let candidates = worker.select_candidates().await.unwrap();
+    assert!(
+        !candidates.contains(&did),
+        "a DID that already has a handle must not be selected"
+    );
 
     // Both rows must still carry the pre-existing handle.
     let (cnt,): (i64,) = sqlx::query_as(
@@ -279,7 +291,16 @@ async fn sync_respects_limit() {
     let stub = StubResolver::new(mapping).into_arc();
 
     let worker = worker_with(db.clone(), stub.clone());
-    let report = worker.run_once().await.unwrap();
+    // The cap lives in the SELECT, so assert it there; the report of a
+    // full `run_once()` depends on what else is pending database-wide.
+    let candidates = worker.select_candidates().await.unwrap();
+    assert!(
+        candidates.len() as i64 <= BATCH_SIZE,
+        "select must never exceed BATCH_SIZE, got {}",
+        candidates.len()
+    );
+    let batch: Vec<String> = all_dids.iter().take(BATCH_SIZE as usize).cloned().collect();
+    let report = worker.resolve_batch(batch).await.unwrap();
     assert_eq!(
         report.resolved as i64,
         BATCH_SIZE,
@@ -339,7 +360,7 @@ async fn sync_skips_unresolvable_dids() {
     let stub = StubResolver::new(HashMap::new()).into_arc();
 
     let worker = worker_with(db.clone(), stub.clone());
-    let report = worker.run_once().await.unwrap();
+    let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
     assert_eq!(report.resolved, 0);
     assert_eq!(report.failed, 0);
     assert_eq!(report.skipped, 1, "{report:?}");
@@ -388,14 +409,21 @@ async fn sync_resolves_did_web_via_web_resolver() {
     let plc_arc: Arc<dyn DidHandleResolver> = plc.into_arc();
     let web_arc: Arc<dyn DidHandleResolver> = web.into_arc();
 
+    // The local PDS is consulted before the method dispatch and does
+    // not host a foreign `did:web:` — wiring one of the other stubs in
+    // here would make it claim a DID it doesn't have, and the test
+    // would assert against the PDS-first rule instead of the dispatch.
+    let pds_arc: Arc<dyn DidHandleResolver> =
+        StubResolver::new(HashMap::new()).into_arc();
+
     let worker = HandleSyncWorker {
         db: db.clone(),
-        pds_resolver: Arc::clone(&plc_arc),
+        pds_resolver: pds_arc,
         plc_resolver: plc_arc,
         web_resolver: web_arc,
         interval_secs: 999,
     };
-    let report = worker.run_once().await.unwrap();
+    let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
     assert_eq!(
         report.resolved, 1,
         "did:web must resolve through the web resolver, got {report:?}"
@@ -442,14 +470,19 @@ async fn sync_resolves_did_plc_via_plc_resolver() {
     let plc_arc: Arc<dyn DidHandleResolver> = plc.into_arc();
     let web_arc: Arc<dyn DidHandleResolver> = web.into_arc();
 
+    // Same reasoning as the did:web test: the PDS doesn't host this
+    // DID, so the method dispatch is what's under test.
+    let pds_arc: Arc<dyn DidHandleResolver> =
+        StubResolver::new(HashMap::new()).into_arc();
+
     let worker = HandleSyncWorker {
         db: db.clone(),
-        pds_resolver: Arc::clone(&plc_arc),
+        pds_resolver: pds_arc,
         plc_resolver: plc_arc,
         web_resolver: web_arc,
         interval_secs: 999,
     };
-    let report = worker.run_once().await.unwrap();
+    let report = worker.resolve_batch(vec![did.clone()]).await.unwrap();
     assert_eq!(
         report.resolved, 1,
         "did:plc must resolve through the PLC resolver, got {report:?}"

crates/appview/tests/notifications_integration.rs

@@ -0,0 +1,777 @@
+//! Integration tests for the Phase-5c read API additions:
+//! `/api/notifications` (+ `/count`, `/seen`), `/api/followers`,
+//! `/api/following` and `/api/thread`.
+//!
+//! Same contract as `api_integration.rs`: these run against a live
+//! appview service + DB and are **fail-open**. If the service or the
+//! database isn't reachable the test prints a notice and returns
+//! success, so `cargo test --workspace` stays green on a machine where
+//! `docker compose up` hasn't been run.
+//!
+//! Notification rows are written by the *indexer*, not by any HTTP
+//! endpoint, so every test here seeds through `/internal/ingest-commit`
+//! (the same path the PDS uses) and then reads back through the public
+//! API. That's deliberate: it's the only way to catch a mismatch
+//! between what the write path stores and what the read path joins.
+
+mod common;
+
+use common::TestAuth;
+use serde_json::{json, Value};
+use std::time::Duration;
+
+/// Base URL of the appview under test. Overridable so the suite can be
+/// pointed at a throwaway instance on a scratch database instead of
+/// whatever the developer happens to have running on the default port.
+fn appview_url() -> String {
+    std::env::var("APPVIEW_TEST_URL")
+        .unwrap_or_else(|_| "http://127.0.0.1:2584".to_string())
+}
+
+async fn client() -> reqwest::Client {
+    reqwest::Client::builder()
+        .timeout(Duration::from_secs(5))
+        .build()
+        .unwrap()
+}
+
+async fn wait_for_appview_db() -> bool {
+    let base = appview_url();
+    let c = client().await;
+    for _ in 0..20 {
+        if let Ok(r) = c.get(format!("{base}/healthz")).send().await {
+            if r.status().is_success() {
+                return true;
+            }
+        }
+        tokio::time::sleep(Duration::from_millis(250)).await;
+    }
+    false
+}
+
+async fn db_pool() -> Option<sqlx::PgPool> {
+    let url = std::env::var("DATABASE_URL_APPVIEW").ok()?;
+    match tokio::time::timeout(Duration::from_secs(2), sqlx::PgPool::connect(&url)).await {
+        Ok(Ok(pool)) => Some(pool),
+        _ => None,
+    }
+}
+
+/// Guard used at the top of every test. Returns `None` (→ skip) unless
+/// the HTTP service is up, the database is reachable, **and** we know
+/// how to authenticate: `/api/notifications*` now requires a token
+/// whose `sub` is the requested DID, and the DIDs seeded here are
+/// synthetic, so the token has to be minted from the PDS's signing
+/// secret. See `tests/common/mod.rs`.
+async fn ready() -> Option<(reqwest::Client, sqlx::PgPool, TestAuth)> {
+    if !wait_for_appview_db().await {
+        eprintln!("appview not running, skipping");
+        return None;
+    }
+    let Some(pool) = db_pool().await else {
+        eprintln!("appview DB unreachable, skipping");
+        return None;
+    };
+    let c = client().await;
+    let auth = TestAuth::probe(&c, &appview_url()).await?;
+    Some((c, pool, auth))
+}
+
+/// `GET <url>` against a private endpoint, carrying the token for
+/// `did` when the instance enforces auth.
+fn authed_get(
+    c: &reqwest::Client,
+    auth: &TestAuth,
+    url: String,
+    did: &str,
+) -> reqwest::RequestBuilder {
+    auth.apply(c.get(url), did)
+}
+
+/// `POST <url>` against a private endpoint. Same rule as
+/// [`authed_get`] — `/api/notifications/seen` is a write into one
+/// user's read state.
+fn authed_post(
+    c: &reqwest::Client,
+    auth: &TestAuth,
+    url: String,
+    did: &str,
+) -> reqwest::RequestBuilder {
+    auth.apply(c.post(url), did)
+}
+
+async fn post_ingest(c: &reqwest::Client, body: Value) -> reqwest::Response {
+    let base = appview_url();
+    c.post(format!("{base}/internal/ingest-commit"))
+        .json(&body)
+        .send()
+        .await
+        .unwrap()
+}
+
+fn did_for_test(name: &str) -> String {
+    format!("did:plc:ntf_{}_{}", name, uuid::Uuid::new_v4().simple())
+}
+
+fn rkey() -> String {
+    uuid::Uuid::new_v4().simple().to_string()
+}
+
+/// Create one post through the ingest path and return its URI.
+async fn seed_post(c: &reqwest::Client, did: &str, text: &str) -> String {
+    let rk = rkey();
+    let r = post_ingest(
+        c,
+        json!({
+            "did": did,
+            "handle": "ntf-fixture.test",
+            "collection": "app.twi.post",
+            "action": "create",
+            "rkey": rk,
+            "cid": "bafyreicid",
+            "record": { "text": text, "createdAt": "2026-07-01T12:00:00Z" }
+        }),
+    )
+    .await;
+    assert_eq!(r.status().as_u16(), 200);
+    format!("at://{did}/app.twi.post/{rk}")
+}
+
+/// Create a reply to `parent_uri` and return the reply's URI.
+async fn seed_reply(
+    c: &reqwest::Client,
+    did: &str,
+    parent_uri: &str,
+    root_uri: &str,
+    text: &str,
+) -> String {
+    let rk = rkey();
+    let r = post_ingest(
+        c,
+        json!({
+            "did": did,
+            "handle": "ntf-fixture.test",
+            "collection": "app.twi.post",
+            "action": "create",
+            "rkey": rk,
+            "cid": "bafyreicid",
+            "record": {
+                "text": text,
+                "createdAt": "2026-07-01T12:05:00Z",
+                "reply": {
+                    "parent": { "uri": parent_uri, "cid": "bafyparent" },
+                    "root":   { "uri": root_uri,   "cid": "bafyroot" }
+                }
+            }
+        }),
+    )
+    .await;
+    assert_eq!(r.status().as_u16(), 200);
+    format!("at://{did}/app.twi.post/{rk}")
+}
+
+async fn seed_like(c: &reqwest::Client, did: &str, post_uri: &str) {
+    let r = post_ingest(
+        c,
+        json!({
+            "did": did,
+            "collection": "app.bsky.feed.like",
+            "action": "create",
+            "rkey": rkey(),
+            "cid": "bafylike",
+            "record": {
+                "subject": { "uri": post_uri, "cid": "bafyreicid" },
+                "createdAt": "2026-07-01T12:01:00Z"
+            }
+        }),
+    )
+    .await;
+    assert_eq!(r.status().as_u16(), 200);
+}
+
+async fn seed_follow(c: &reqwest::Client, follower: &str, subject: &str) {
+    let r = post_ingest(
+        c,
+        json!({
+            "did": follower,
+            "collection": "app.bsky.graph.follow",
+            "action": "create",
+            "rkey": rkey(),
+            "subject_did": subject,
+            "record": { "subject": subject, "createdAt": "2026-01-01T00:00:00Z" }
+        }),
+    )
+    .await;
+    assert_eq!(r.status().as_u16(), 200);
+}
+
+// -- notifications ----------------------------------------------------------
+
+/// A like, a repost-free reply and a follow from three different
+/// people must show up as three hydrated notification rows, and the
+/// unread count must agree with the list.
+#[tokio::test]
+async fn notifications_list_count_and_seen() {
+    let base = appview_url();
+    let Some((c, _pool, auth)) = ready().await else {
+        return;
+    };
+    let alice = did_for_test("alice");
+    let bob = did_for_test("bob");
+    let carol = did_for_test("carol");
+
+    // Alice posts; bob likes it and carol replies; bob also follows her.
+    let post_uri = seed_post(&c, &alice, "alice's original").await;
+    seed_post(&c, &bob, "bob exists").await;
+    seed_post(&c, &carol, "carol exists").await;
+    seed_like(&c, &bob, &post_uri).await;
+    let reply_uri = seed_reply(&c, &carol, &post_uri, &post_uri, "carol's reply").await;
+    seed_follow(&c, &bob, &alice).await;
+
+    let resp = authed_get(&c, &auth, format!("{base}/api/notifications"), &alice)
+        .query(&[("did", alice.as_str()), ("limit", "50")])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status().as_u16(), 200);
+    let body: Value = resp.json().await.unwrap();
+    let items = body["notifications"].as_array().expect("notifications array");
+    assert_eq!(items.len(), 3, "expected like + reply + follow, got {items:?}");
+
+    // Newest first: `indexed_at` must be non-increasing down the list.
+    let mut prev: Option<String> = None;
+    for n in items {
+        let at = n["indexed_at"].as_str().unwrap().to_string();
+        if let Some(p) = prev.take() {
+            assert!(at <= p, "indexed_at must be non-increasing: {at} <= {p}");
+        }
+        prev = Some(at);
+    }
+
+    let by_kind = |k: &str| -> Value {
+        items
+            .iter()
+            .find(|n| n["kind"] == json!(k))
+            .unwrap_or_else(|| panic!("missing {k} notification in {items:?}"))
+            .clone()
+    };
+
+    // The like points at alice's own post and previews its text.
+    let like = by_kind("like");
+    assert_eq!(like["author_did"], json!(bob));
+    assert_eq!(like["subject_uri"], json!(post_uri));
+    assert_eq!(like["subject_text"], json!("alice's original"));
+    assert!(like["read_at"].is_null(), "new notifications start unread");
+
+    // The reply points at the REPLY (not the parent), so the preview
+    // shows what carol wrote.
+    let reply = by_kind("reply");
+    assert_eq!(reply["author_did"], json!(carol));
+    assert_eq!(reply["subject_uri"], json!(reply_uri));
+    assert_eq!(reply["subject_text"], json!("carol's reply"));
+
+    // A follow has no subject at all.
+    let follow = by_kind("follow");
+    assert_eq!(follow["author_did"], json!(bob));
+    assert!(follow["subject_uri"].is_null());
+
+    // `author_handle` is never empty and never carries a leading '@'
+    // (the UI renders `@{handle}` itself).
+    for n in items {
+        let h = n["author_handle"].as_str().expect("author_handle is a string");
+        assert!(!h.is_empty(), "author_handle must never be empty: {n:?}");
+        assert!(!h.starts_with('@'), "author_handle must not carry a sigil: {h}");
+    }
+
+    // The unread count agrees with the list.
+    let resp = authed_get(&c, &auth, format!("{base}/api/notifications/count"), &alice)
+        .query(&[("did", alice.as_str())])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status().as_u16(), 200);
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(body["count"], json!(3));
+
+    // Mark everything seen.
+    let resp = authed_post(&c, &auth, format!("{base}/api/notifications/seen"), &alice)
+        .json(&json!({ "did": alice }))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status().as_u16(), 200);
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(body["ok"], json!(true));
+    assert_eq!(body["updated"], json!(3));
+
+    // Idempotent: a second call updates nothing and still succeeds.
+    let resp = authed_post(&c, &auth, format!("{base}/api/notifications/seen"), &alice)
+        .json(&json!({ "did": alice }))
+        .send()
+        .await
+        .unwrap();
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(body["updated"], json!(0));
+
+    // Count is now zero and the rows carry a read_at.
+    let resp = authed_get(&c, &auth, format!("{base}/api/notifications/count"), &alice)
+        .query(&[("did", alice.as_str())])
+        .send()
+        .await
+        .unwrap();
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(body["count"], json!(0));
+
+    let resp = authed_get(&c, &auth, format!("{base}/api/notifications"), &alice)
+        .query(&[("did", alice.as_str())])
+        .send()
+        .await
+        .unwrap();
+    let body: Value = resp.json().await.unwrap();
+    for n in body["notifications"].as_array().unwrap() {
+        assert!(!n["read_at"].is_null(), "row should be read now: {n:?}");
+    }
+
+    // `did` is mandatory on all three.
+    for path in [
+        "/api/notifications",
+        "/api/notifications/count",
+    ] {
+        let resp = authed_get(&c, &auth, format!("{base}{path}"), &alice)
+            .query(&[("did", "")])
+            .send()
+            .await
+            .unwrap();
+        assert_eq!(resp.status().as_u16(), 400, "{path} must reject an empty did");
+    }
+}
+
+/// Self-interactions produce nothing: alice liking and replying to her
+/// own post leaves her notification list empty.
+#[tokio::test]
+async fn notifications_skip_self_interactions() {
+    let base = appview_url();
+    let Some((c, _pool, auth)) = ready().await else {
+        return;
+    };
+    let alice = did_for_test("solo");
+    let post_uri = seed_post(&c, &alice, "talking to myself").await;
+    seed_like(&c, &alice, &post_uri).await;
+    seed_reply(&c, &alice, &post_uri, &post_uri, "and replying too").await;
+    seed_follow(&c, &alice, &alice).await;
+
+    let resp = authed_get(&c, &auth, format!("{base}/api/notifications"), &alice)
+        .query(&[("did", alice.as_str())])
+        .send()
+        .await
+        .unwrap();
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(
+        body["notifications"].as_array().unwrap().len(),
+        0,
+        "self-interactions must not notify: {body:?}"
+    );
+}
+
+/// Cursor pagination over the notification list: pages must be
+/// disjoint, exactly `limit` long while more remain, and the cursor
+/// must go null at the end.
+#[tokio::test]
+async fn notifications_paginate_with_cursor() {
+    let base = appview_url();
+    let Some((c, _pool, auth)) = ready().await else {
+        return;
+    };
+    let alice = did_for_test("popular");
+    let post_uri = seed_post(&c, &alice, "the post everyone likes").await;
+
+    // 12 distinct likers → 12 notifications. (Distinct DIDs matter:
+    // the dedupe index is per (recipient, author, kind, subject).)
+    for i in 0..12 {
+        let liker = did_for_test(&format!("fan{i}"));
+        seed_like(&c, &liker, &post_uri).await;
+    }
+
+    let page = |cursor: Option<String>| {
+        let c = c.clone();
+        let alice = alice.clone();
+        let base = base.clone();
+        let auth = auth.clone();
+        async move {
+            let mut req = authed_get(&c, &auth, format!("{base}/api/notifications"), &alice)
+                .query(&[("did", alice.as_str()), ("limit", "5")]);
+            if let Some(cur) = cursor {
+                req = req.query(&[("cursor", cur.as_str())]);
+            }
+            let resp = req.send().await.unwrap();
+            assert_eq!(resp.status().as_u16(), 200);
+            resp.json::<Value>().await.unwrap()
+        }
+    };
+
+    let p1 = page(None).await;
+    assert_eq!(p1["notifications"].as_array().unwrap().len(), 5);
+    let c1 = p1["cursor"].as_str().expect("page1 cursor").to_string();
+
+    let p2 = page(Some(c1)).await;
+    assert_eq!(p2["notifications"].as_array().unwrap().len(), 5);
+    let c2 = p2["cursor"].as_str().expect("page2 cursor").to_string();
+
+    let p3 = page(Some(c2)).await;
+    assert_eq!(p3["notifications"].as_array().unwrap().len(), 2);
+    assert!(
+        p3["cursor"].is_null(),
+        "cursor must be null on the last page: {p3:?}"
+    );
+
+    // No id may appear on two pages.
+    let ids = |p: &Value| -> Vec<i64> {
+        p["notifications"]
+            .as_array()
+            .unwrap()
+            .iter()
+            .map(|n| n["id"].as_i64().unwrap())
+            .collect()
+    };
+    let mut all: Vec<i64> = ids(&p1);
+    all.extend(ids(&p2));
+    all.extend(ids(&p3));
+    let unique: std::collections::HashSet<i64> = all.iter().copied().collect();
+    assert_eq!(unique.len(), all.len(), "pages overlap: {all:?}");
+    assert_eq!(all.len(), 12);
+
+    // A mangled cursor is a 400, not a silent restart at page 1.
+    let resp = authed_get(&c, &auth, format!("{base}/api/notifications"), &alice)
+        .query(&[("did", alice.as_str()), ("cursor", "!!!garbage!!!")])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status().as_u16(), 400);
+}
+
+/// `seenAt` is a watermark: only rows indexed at or before it flip to
+/// read. Accepted in both camelCase and snake_case.
+#[tokio::test]
+async fn notifications_seen_respects_watermark() {
+    let base = appview_url();
+    let Some((c, _pool, auth)) = ready().await else {
+        return;
+    };
+    let alice = did_for_test("watermark");
+    let post_uri = seed_post(&c, &alice, "watermark subject").await;
+
+    let first = did_for_test("early");
+    seed_like(&c, &first, &post_uri).await;
+
+    // Read back the first notification's indexed_at — that's the
+    // watermark a client would echo after rendering page 1.
+    let body: Value = authed_get(&c, &auth, format!("{base}/api/notifications"), &alice)
+        .query(&[("did", alice.as_str())])
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    let watermark = body["notifications"][0]["indexed_at"]
+        .as_str()
+        .unwrap()
+        .to_string();
+
+    // A second interaction lands *after* the watermark.
+    tokio::time::sleep(Duration::from_millis(20)).await;
+    let second = did_for_test("late");
+    seed_like(&c, &second, &post_uri).await;
+
+    let resp = authed_post(&c, &auth, format!("{base}/api/notifications/seen"), &alice)
+        .json(&json!({ "did": alice, "seenAt": watermark }))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status().as_u16(), 200);
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(
+        body["updated"], json!(1),
+        "only the row at/before the watermark may flip to read"
+    );
+
+    // The later one is still unread.
+    let body: Value = authed_get(&c, &auth, format!("{base}/api/notifications/count"), &alice)
+        .query(&[("did", alice.as_str())])
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(body["count"], json!(1));
+
+    // snake_case spelling must work identically.
+    let resp = authed_post(&c, &auth, format!("{base}/api/notifications/seen"), &alice)
+        .json(&json!({ "did": alice, "seen_at": null }))
+        .send()
+        .await
+        .unwrap();
+    let body: Value = resp.json().await.unwrap();
+    assert_eq!(body["updated"], json!(1));
+}
+
+// -- follower / following lists ---------------------------------------------
+
+#[tokio::test]
+async fn followers_and_following_lists() {
+    let base = appview_url();
+    let Some((c, _pool, _auth)) = ready().await else {
+        return;
+    };
+    let hub = did_for_test("hub");
+    seed_post(&c, &hub, "hub post").await;
+
+    // Three people follow the hub; the hub follows one of them back.
+    let mut fans = Vec::new();
+    for i in 0..3 {
+        let fan = did_for_test(&format!("fan{i}"));
+        seed_post(&c, &fan, "fan post").await;
+        seed_follow(&c, &fan, &hub).await;
+        fans.push(fan);
+    }
+    seed_follow(&c, &hub, &fans[0]).await;
+
+    // Followers.
+    let body: Value = c
+        .get(format!("{base}/api/followers"))
+        .query(&[("did", hub.as_str()), ("limit", "50")])
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    let got: std::collections::HashSet<String> = body["profiles"]
+        .as_array()
+        .expect("profiles array")
+        .iter()
+        .map(|p| p["did"].as_str().unwrap().to_string())
+        .collect();
+    for fan in &fans {
+        assert!(got.contains(fan), "follower {fan} missing from {body:?}");
+    }
+    assert!(
+        !got.contains(&hub),
+        "the hub must not appear in its own follower list"
+    );
+
+    // Following — exactly one edge.
+    let body: Value = c
+        .get(format!("{base}/api/following"))
+        .query(&[("did", hub.as_str()), ("limit", "50")])
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    let following: Vec<String> = body["profiles"]
+        .as_array()
+        .unwrap()
+        .iter()
+        .map(|p| p["did"].as_str().unwrap().to_string())
+        .collect();
+    assert_eq!(following, vec![fans[0].clone()]);
+
+    // Never an empty or '@'-prefixed handle.
+    for p in body["profiles"].as_array().unwrap() {
+        let h = p["handle"].as_str().expect("handle is a string");
+        assert!(!h.is_empty());
+        assert!(!h.starts_with('@'));
+    }
+
+    // Pagination: limit=1 must page through all three followers
+    // without repeats.
+    let mut seen: Vec<String> = Vec::new();
+    let mut cursor: Option<String> = None;
+    for _ in 0..5 {
+        let mut req = c
+            .get(format!("{base}/api/followers"))
+            .query(&[("did", hub.as_str()), ("limit", "1")]);
+        if let Some(cur) = cursor.as_deref() {
+            req = req.query(&[("cursor", cur)]);
+        }
+        let body: Value = req.send().await.unwrap().json().await.unwrap();
+        for p in body["profiles"].as_array().unwrap() {
+            seen.push(p["did"].as_str().unwrap().to_string());
+        }
+        match body["cursor"].as_str() {
+            Some(c) => cursor = Some(c.to_string()),
+            None => break,
+        }
+    }
+    let unique: std::collections::HashSet<&String> = seen.iter().collect();
+    assert_eq!(unique.len(), seen.len(), "paged followers repeat: {seen:?}");
+    assert_eq!(seen.len(), 3, "paging lost a follower: {seen:?}");
+
+    // `did` is mandatory. These two stay public — a follow edge is a
+    // public record — so no token is involved.
+    for path in ["/api/followers", "/api/following"] {
+        let resp = c
+            .get(format!("{base}{path}"))
+            .query(&[("did", "")])
+            .send()
+            .await
+            .unwrap();
+        assert_eq!(resp.status().as_u16(), 400);
+    }
+}
+
+// -- thread -----------------------------------------------------------------
+
+/// `/api/thread` returns the ancestor chain above a post and its
+/// direct replies, in both the query-param and the path spelling.
+#[tokio::test]
+async fn thread_returns_parents_and_replies() {
+    let base = appview_url();
+    let Some((c, _pool, _auth)) = ready().await else {
+        return;
+    };
+    let a = did_for_test("root");
+    let b = did_for_test("mid");
+    let d = did_for_test("leaf");
+
+    let root = seed_post(&c, &a, "root post").await;
+    let mid = seed_reply(&c, &b, &root, &root, "middle reply").await;
+    let leaf = seed_reply(&c, &d, &mid, &root, "leaf reply").await;
+
+    for url in [
+        format!("{base}/api/thread?uri={}", urlencoding(&mid)),
+        format!("{base}/api/thread/{mid}"),
+    ] {
+        let resp = c.get(&url).send().await.unwrap();
+        assert_eq!(resp.status().as_u16(), 200, "GET {url}");
+        let body: Value = resp.json().await.unwrap();
+
+        assert_eq!(body["post"]["uri"], json!(mid), "GET {url}");
+        // One ancestor, and it's the root.
+        let parents = body["parents"].as_array().unwrap();
+        assert_eq!(parents.len(), 1, "GET {url}: {parents:?}");
+        assert_eq!(parents[0]["uri"], json!(root));
+        assert_eq!(body["root"]["uri"], json!(root));
+        // One direct reply: the leaf.
+        let replies = body["replies"].as_array().unwrap();
+        assert_eq!(replies.len(), 1, "GET {url}: {replies:?}");
+        assert_eq!(replies[0]["uri"], json!(leaf));
+        assert_eq!(body["like_count"], json!(0));
+    }
+
+    // The root's thread has no parents and one reply (the middle).
+    let body: Value = c
+        .get(format!("{base}/api/thread/{root}"))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(body["parents"].as_array().unwrap().len(), 0);
+    assert!(body["root"].is_null(), "a top-level post has no root ref");
+    let replies = body["replies"].as_array().unwrap();
+    assert_eq!(replies.len(), 1);
+    assert_eq!(replies[0]["uri"], json!(mid));
+
+    // An unknown URI is a 200 with a null post, not a 404 — the UI
+    // renders "not in index" from one field check.
+    let body: Value = c
+        .get(format!(
+            "{base}/api/thread/at://did:plc:nobody/app.twi.post/{}",
+            rkey()
+        ))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert!(body["post"].is_null());
+    assert_eq!(body["parents"].as_array().unwrap().len(), 0);
+    assert_eq!(body["replies"].as_array().unwrap().len(), 0);
+
+    // A missing `uri` is a 400.
+    let resp = c
+        .get(format!("{base}/api/thread"))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status().as_u16(), 400);
+}
+
+/// `/api/post/{uri}` must keep its historical shape after the thread
+/// refactor — the Tauri client reads `thread.parent` / `thread.root`
+/// and has no `parents` / `replies` fields.
+#[tokio::test]
+async fn post_by_uri_stays_backwards_compatible() {
+    let base = appview_url();
+    let Some((c, _pool, _auth)) = ready().await else {
+        return;
+    };
+    let a = did_for_test("compat_a");
+    let b = did_for_test("compat_b");
+    let root = seed_post(&c, &a, "compat root").await;
+    let mid = seed_reply(&c, &b, &root, &root, "compat reply").await;
+    seed_like(&c, &a, &mid).await;
+
+    let body: Value = c
+        .get(format!("{base}/api/post/{mid}"))
+        .query(&[("viewer_did", a.as_str())])
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+
+    assert_eq!(body["post"]["uri"], json!(mid));
+    // The legacy nested shape: immediate parent + root, both hydrated.
+    assert_eq!(body["thread"]["parent"]["uri"], json!(root));
+    assert_eq!(body["thread"]["root"]["uri"], json!(root));
+    assert_eq!(body["like_count"], json!(1));
+    assert_eq!(body["repost_count"], json!(0));
+    assert_eq!(body["viewer_liked"], json!(true));
+    assert_eq!(body["viewer_reposted"], json!(false));
+    // The endpoint must NOT have grown the thread route's fields.
+    assert!(body.get("replies").is_none(), "unexpected `replies`: {body:?}");
+    assert!(body.get("parents").is_none(), "unexpected `parents`: {body:?}");
+
+    // And the two endpoints must agree about the parent / root.
+    let thread: Value = c
+        .get(format!("{base}/api/thread/{mid}"))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(
+        thread["parents"].as_array().unwrap().last().unwrap()["uri"],
+        body["thread"]["parent"]["uri"],
+        "/api/thread and /api/post disagree about the parent"
+    );
+    assert_eq!(thread["root"]["uri"], body["thread"]["root"]["uri"]);
+}
+
+/// Minimal percent-encoder for the `?uri=` form. Only the characters
+/// an `at://did:plc:…/app.twi.post/<rkey>` URI can contain that a query
+/// string would otherwise eat.
+fn urlencoding(s: &str) -> String {
+    let mut out = String::with_capacity(s.len() * 2);
+    for ch in s.chars() {
+        match ch {
+            'A'..='Z' | 'a'..='z' | '0'..='9' | '-' | '_' | '.' | '~' => out.push(ch),
+            other => {
+                let mut buf = [0u8; 4];
+                for b in other.encode_utf8(&mut buf).as_bytes() {
+                    out.push_str(&format!("%{b:02X}"));
+                }
+            }
+        }
+    }
+    out
+}

crates/at-blob/src/store.rs

@@ -1,7 +1,10 @@
 use anyhow::Result;
 use async_trait::async_trait;
+use at_crypto::cid::{cid_for_raw, sha256};
 use bytes::Bytes;
 use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+use tokio::sync::RwLock;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct BlobInfo {
@@ -19,20 +22,116 @@ pub trait BlobStore: Send + Sync {
     async fn public_url(&self, key: &str) -> Result<String>;
 }
 
-pub struct InMemoryBlobStore;
+/// In-process blob store backed by a `HashMap` guarded by a
+/// [`tokio::sync::RwLock`]. Used in tests and any dev/single-node
+/// deployment that doesn't need a real object store.
+///
+/// Behaves like [`crate::s3::S3BlobStore`] with respect to `BlobInfo`
+/// (same CID computation over the raw bytes, same field semantics) so
+/// tests can swap one for the other transparently. Data does not
+/// survive process restarts.
+#[derive(Default)]
+pub struct InMemoryBlobStore {
+    blobs: RwLock<HashMap<String, (Bytes, String /* mime */)>>,
+}
+
+impl InMemoryBlobStore {
+    pub fn new() -> Self {
+        Self::default()
+    }
+}
 
 #[async_trait]
 impl BlobStore for InMemoryBlobStore {
-    async fn put(&self, _key: &str, _data: Bytes, _mime: &str) -> Result<BlobInfo> {
+    async fn put(&self, key: &str, data: Bytes, mime: &str) -> Result<BlobInfo> {
-        unimplemented!("in-memory blob store placeholder")
+        let hash = sha256(&data);
+        let cid = cid_for_raw(0x55, hash)?;
+        let size = data.len() as u64;
+        self.blobs
+            .write()
+            .await
+            .insert(key.to_string(), (data, mime.to_string()));
+        Ok(BlobInfo {
+            cid: cid.to_string(),
+            mime_type: mime.to_string(),
+            size,
+            storage_key: key.to_string(),
+        })
     }
-    async fn get(&self, _key: &str) -> Result<Option<Bytes>> {
+
-        unimplemented!()
+    async fn get(&self, key: &str) -> Result<Option<Bytes>> {
+        Ok(self
+            .blobs
+            .read()
+            .await
+            .get(key)
+            .map(|(data, _mime)| data.clone()))
     }
-    async fn delete(&self, _key: &str) -> Result<()> {
+
-        unimplemented!()
+    async fn delete(&self, key: &str) -> Result<()> {
+        self.blobs.write().await.remove(key);
+        Ok(())
     }
-    async fn public_url(&self, _key: &str) -> Result<String> {
+
-        unimplemented!()
+    async fn public_url(&self, key: &str) -> Result<String> {
+        Ok(format!("/blob/{key}"))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn put_get_roundtrip() {
+        let store = InMemoryBlobStore::new();
+        let data = Bytes::from_static(b"hello world");
+        let info = store.put("k1", data.clone(), "text/plain").await.unwrap();
+        assert_eq!(info.storage_key, "k1");
+        assert_eq!(info.mime_type, "text/plain");
+        assert_eq!(info.size, data.len() as u64);
+
+        let got = store.get("k1").await.unwrap();
+        assert_eq!(got, Some(data));
+    }
+
+    #[tokio::test]
+    async fn get_missing_key_returns_none() {
+        let store = InMemoryBlobStore::new();
+        let got = store.get("does-not-exist").await.unwrap();
+        assert_eq!(got, None);
+    }
+
+    #[tokio::test]
+    async fn delete_then_get_returns_none() {
+        let store = InMemoryBlobStore::new();
+        store
+            .put("k2", Bytes::from_static(b"data"), "application/octet-stream")
+            .await
+            .unwrap();
+        store.delete("k2").await.unwrap();
+        let got = store.get("k2").await.unwrap();
+        assert_eq!(got, None);
+    }
+
+    #[tokio::test]
+    async fn delete_missing_key_is_ok() {
+        let store = InMemoryBlobStore::new();
+        store.delete("never-existed").await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn same_bytes_produce_same_cid() {
+        let store = InMemoryBlobStore::new();
+        let data = Bytes::from_static(b"identical payload");
+        let info_a = store
+            .put("key-a", data.clone(), "application/octet-stream")
+            .await
+            .unwrap();
+        let info_b = store
+            .put("key-b", data.clone(), "application/octet-stream")
+            .await
+            .unwrap();
+        assert_eq!(info_a.cid, info_b.cid);
     }
 }

crates/at-shared/src/config.rs

@@ -7,6 +7,17 @@ fn default_handle_sync_interval() -> u64 {
     300
 }
 
+/// Default for `APPVIEW_AUTH_REQUIRED`.
+///
+/// `true` — the AppView's private endpoints (notifications, home
+/// timeline) reject unauthenticated requests. Fail closed: an operator
+/// who forgets the variable gets the safe behaviour, and the only way
+/// to serve another user's notifications to an anonymous caller is to
+/// opt out explicitly.
+fn default_auth_required() -> bool {
+    true
+}
+
 #[derive(Debug, Clone, Deserialize)]
 pub struct AppConfig {
     pub pds_host: String,
@@ -46,6 +57,27 @@ pub struct AppConfig {
     /// directory. Default: 300s (5 minutes).
     #[serde(default = "default_handle_sync_interval")]
     pub appview_handle_sync_interval_secs: u64,
+    /// Whether the AppView enforces bearer-token auth on the endpoints
+    /// that serve a single user's private data (`/api/notifications*`,
+    /// `/api/timeline/home`). Default `true`.
+    ///
+    /// Set `APPVIEW_AUTH_REQUIRED=false` to get the pre-auth behaviour
+    /// (every endpoint public). That mode exists for two callers:
+    /// the fail-open integration suites, which seed synthetic DIDs the
+    /// PDS has never issued a token for, and an instance that is
+    /// already isolated at the network layer (VPN / private subnet).
+    /// The AppView warns loudly at startup when it is off.
+    #[serde(default = "default_auth_required")]
+    pub appview_auth_required: bool,
+    /// Browser origins allowed to call the AppView's `/api/*` routes,
+    /// from the comma-separated `APPVIEW_CORS_ORIGINS`. Empty means
+    /// "no allowlist configured" — the AppView then keeps the historic
+    /// `Access-Control-Allow-Origin: *` behaviour and warns at startup.
+    ///
+    /// Example (Tauri webview origins differ per platform):
+    /// `APPVIEW_CORS_ORIGINS=tauri://localhost,http://127.0.0.1:1430`
+    #[serde(default)]
+    pub appview_cors_origins: Vec<String>,
 }
 
 impl AppConfig {
@@ -82,6 +114,183 @@ impl AppConfig {
                 .ok()
                 .and_then(|s| s.parse().ok())
                 .unwrap_or_else(default_handle_sync_interval),
+            appview_auth_required: std::env::var("APPVIEW_AUTH_REQUIRED")
+                .ok()
+                .map(|s| parse_bool_env(&s))
+                .unwrap_or_else(default_auth_required),
+            appview_cors_origins: std::env::var("APPVIEW_CORS_ORIGINS")
+                .ok()
+                .map(|s| parse_csv_env(&s))
+                .unwrap_or_default(),
         })
     }
+
+    /// The `did:web:` DID of *this* PDS, derived from `PDS_PUBLIC_URL`.
+    ///
+    /// One derivation, two consumers: `com.atproto.server.describeServer`
+    /// (which used to return a hardcoded `did:web:pds.maarcadetweet.local`
+    /// no matter what the operator configured) and
+    /// `GET /.well-known/did.json`, which publishes the server's signing
+    /// key under exactly this id. If those two ever disagreed, a client
+    /// that trusts `describeServer` would fetch the key document of a
+    /// different identity.
+    pub fn pds_did(&self) -> String {
+        did_web_from_url(&self.pds_public_url)
+    }
+
+    /// Base URL the AppView uses to reach the PDS.
+    ///
+    /// `PDS_INTERNAL_URL` when set (the cluster-internal hostname),
+    /// otherwise `PDS_PUBLIC_URL`. Both the handle-sync resolver and the
+    /// signing-key fetch go through here, so the two can't end up
+    /// talking to different PDS instances.
+    pub fn pds_base_url(&self) -> String {
+        self.pds_internal_url
+            .clone()
+            .unwrap_or_else(|| self.pds_public_url.clone())
+    }
+}
+
+/// Interpret an environment variable as a boolean.
+///
+/// Accepts the spellings people actually type in a `.env` file. Anything
+/// unrecognised counts as `false` for an explicitly-set variable — the
+/// caller decides what an *absent* variable means (see
+/// [`default_auth_required`]), and a typo like `APPVIEW_AUTH_REQUIRED=ture`
+/// must never silently read as "on" when the operator's intent was to
+/// switch something off... nor as "off" for a security switch. Since
+/// this is only reached when the variable *is* set, and the only
+/// security-relevant user of it defaults to `true` when unset, we treat
+/// unknown values as `false` and rely on the startup warning to make a
+/// disabled auth switch impossible to miss in the logs.
+fn parse_bool_env(raw: &str) -> bool {
+    matches!(
+        raw.trim().to_ascii_lowercase().as_str(),
+        "1" | "true" | "yes" | "on"
+    )
+}
+
+/// Split a comma-separated environment variable into trimmed,
+/// non-empty entries. `"a, b,,c "` → `["a", "b", "c"]`.
+fn parse_csv_env(raw: &str) -> Vec<String> {
+    raw.split(',')
+        .map(|s| s.trim().to_string())
+        .filter(|s| !s.is_empty())
+        .collect()
+}
+
+/// Turn an `http(s)://host[:port][/path]` URL into a `did:web:` DID.
+///
+/// The did:web method spec maps the authority to the method-specific
+/// id, with two wrinkles that matter here:
+///
+///  - a port is **percent-encoded** (`:` → `%3A`), because a bare colon
+///    already separates the DID's own segments. `http://127.0.0.1:2583`
+///    is therefore `did:web:127.0.0.1%3A2583`, *not*
+///    `did:web:127.0.0.1:2583` (which would parse as host `127.0.0.1`
+///    plus a path segment `2583`).
+///  - path segments, if any, are appended separated by `:`.
+///
+/// The default ports (80/443) are kept rather than stripped: the
+/// resolution rule is a textual one, and a client that reverses this
+/// mapping has to end up at the same URL we serve the document from.
+pub fn did_web_from_url(url: &str) -> String {
+    // Strip the scheme. We accept a bare `host:port` too, which is what
+    // a misconfigured `PDS_PUBLIC_URL` often contains.
+    let rest = url
+        .trim()
+        .trim_start_matches("https://")
+        .trim_start_matches("http://")
+        .trim_end_matches('/');
+    // Drop any userinfo (`user@host`) and query/fragment — neither has
+    // a place in a did:web identifier.
+    let rest = rest.split(['?', '#']).next().unwrap_or(rest);
+    let rest = rest.rsplit('@').next().unwrap_or(rest);
+
+    let mut parts = rest.split('/');
+    let authority = parts.next().unwrap_or("");
+    let host = authority.replacen(':', "%3A", 1);
+    let mut did = format!("did:web:{host}");
+    for segment in parts.filter(|s| !s.is_empty()) {
+        did.push(':');
+        did.push_str(segment);
+    }
+    did
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn did_web_encodes_port_as_percent_3a() {
+        // The dev default. A literal colon here would be read as a
+        // did:web path segment, so it has to be percent-encoded.
+        assert_eq!(
+            did_web_from_url("http://127.0.0.1:2583"),
+            "did:web:127.0.0.1%3A2583"
+        );
+        assert_eq!(
+            did_web_from_url("https://pds.example.com:8443"),
+            "did:web:pds.example.com%3A8443"
+        );
+    }
+
+    #[test]
+    fn did_web_without_port_is_plain_host() {
+        assert_eq!(
+            did_web_from_url("https://pds.maarcadetweet.local"),
+            "did:web:pds.maarcadetweet.local"
+        );
+        // Trailing slash must not produce an empty path segment.
+        assert_eq!(
+            did_web_from_url("https://pds.example.com/"),
+            "did:web:pds.example.com"
+        );
+        // Scheme-less input is tolerated.
+        assert_eq!(did_web_from_url("pds.example.com"), "did:web:pds.example.com");
+    }
+
+    #[test]
+    fn did_web_appends_path_segments_with_colons() {
+        assert_eq!(
+            did_web_from_url("https://example.com/user/alice"),
+            "did:web:example.com:user:alice"
+        );
+        // Port + path together: only the port gets percent-encoded.
+        assert_eq!(
+            did_web_from_url("http://example.com:2583/pds"),
+            "did:web:example.com%3A2583:pds"
+        );
+    }
+
+    #[test]
+    fn did_web_ignores_userinfo_query_and_fragment() {
+        assert_eq!(
+            did_web_from_url("https://user@example.com?x=1#frag"),
+            "did:web:example.com"
+        );
+    }
+
+    #[test]
+    fn bool_env_accepts_common_spellings() {
+        for on in ["1", "true", "TRUE", "  yes ", "on"] {
+            assert!(parse_bool_env(on), "{on} should parse as true");
+        }
+        for off in ["0", "false", "no", "off", "", "nonsense"] {
+            assert!(!parse_bool_env(off), "{off} should parse as false");
+        }
+    }
+
+    #[test]
+    fn csv_env_trims_and_drops_empties() {
+        assert_eq!(
+            parse_csv_env("tauri://localhost, http://127.0.0.1:1430 ,,"),
+            vec![
+                "tauri://localhost".to_string(),
+                "http://127.0.0.1:1430".to_string()
+            ]
+        );
+        assert!(parse_csv_env("   ").is_empty());
+    }
 }

crates/pds-server/Cargo.toml

@@ -15,6 +15,7 @@ path = "src/main.rs"
 
 [dependencies]
 tokio = { workspace = true }
+dotenvy = { workspace = true }
 axum = { workspace = true }
 tower = { workspace = true }
 tower-http = { workspace = true }

crates/pds-server/src/jwt_issuer.rs

@@ -39,7 +39,13 @@ pub fn issue_access_jwt(
     let now = chrono::Utc::now().timestamp();
     let exp = now + 3600;
     let claims = JwtClaims {
-        iss: format!("did:web:{}", cfg.pds_public_url.trim_start_matches("http://").trim_start_matches("https://")),
+        // Same derivation as `describeServer` and `/.well-known/did.json`
+        // (`AppConfig::pds_did`), so a verifier can take `iss`, resolve
+        // the did:web document and arrive at the key this token is
+        // signed with. The previous inline version dropped the
+        // percent-encoding of the port, producing an `iss` that no
+        // did:web resolver could follow.
+        iss: cfg.pds_did(),
         sub: did.to_string(),
         aud: "did:web:appview.maarcadetweet.local".into(),
         iat: now,

crates/pds-server/src/main.rs

@@ -17,6 +17,12 @@ use tracing_subscriber::EnvFilter;
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
+    // Load `.env` from the working directory (and upwards) if present.
+    // Nothing else in the process reads it, so without this
+    // `cp .env.example .env && cargo run` fails with `missing env:
+    // PDS_HOST`. Real environment variables always win over the file.
+    let _ = dotenvy::dotenv();
+
     tracing_subscriber::fmt()
         .with_env_filter(EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("info")))
         .init();
@@ -67,6 +73,7 @@ pub fn router(state: AppState) -> Router {
     Router::new()
         .route("/", get(root))
         .route("/healthz", get(healthz))
+        .route("/.well-known/did.json", get(did_document))
         .route(
             "/xrpc/com.atproto.server.describeServer",
             get(describe_server),
@@ -157,9 +164,69 @@ async fn healthz() -> Json<serde_json::Value> {
     Json(json!({ "ok": true }))
 }
 
+/// `GET /.well-known/did.json` — the PDS's own DID document.
+///
+/// This is how the AppView (and any other relying party) learns the
+/// P-256 public key that the access JWTs in
+/// `Authorization: Bearer …` are signed with. Without it the AppView
+/// could not verify a token at all, and the only alternative would be
+/// shipping `PDS_JWT_SECRET` to a second service — a private signing
+/// key crossing a service boundary, for a check that needs nothing but
+/// the public half.
+///
+/// Nothing in this response is secret. `publicKeyMultibase` is the
+/// uncompressed P-256 point derived from `PDS_JWT_SECRET` by
+/// [`jwt_issuer::server_p256_public_multibase`]; the secret itself
+/// never leaves this process.
+///
+/// The document id is [`AppConfig::pds_did`], i.e. it follows
+/// `PDS_PUBLIC_URL` — so a `did:web:` resolver that starts from the DID,
+/// rebuilds the URL and fetches this path lands back here rather than at
+/// some other host's document.
+async fn did_document(State(state): State<AppState>) -> Result<Json<serde_json::Value>, (axum::http::StatusCode, Json<serde_json::Value>)> {
+    let did = state.cfg.pds_did();
+    let public_multibase = jwt_issuer::server_p256_public_multibase(&state.cfg).map_err(|e| {
+        // A malformed `PDS_JWT_SECRET` is the one way this fails, and
+        // it is exactly the failure that also breaks every token this
+        // server issues — surface it instead of publishing a document
+        // with a missing key.
+        (
+            axum::http::StatusCode::INTERNAL_SERVER_ERROR,
+            Json(json!({
+                "error": "InternalServerError",
+                "message": format!("server key unavailable: {e}"),
+            })),
+        )
+    })?;
+    Ok(Json(json!({
+        "@context": [
+            "https://www.w3.org/ns/did/v1",
+            "https://w3id.org/security/multikey/v1",
+        ],
+        "id": did,
+        "verificationMethod": [{
+            // `#atproto` is the fragment AT Proto uses for a repo's
+            // signing key; we reuse it for the server key so a generic
+            // did:web consumer finds it in the usual place.
+            "id": format!("{did}#atproto"),
+            "type": "Multikey",
+            "controller": did,
+            "publicKeyMultibase": public_multibase,
+        }],
+        "service": [{
+            "id": "#atproto_pds",
+            "type": "AtprotoPersonalDataServer",
+            "serviceEndpoint": state.cfg.pds_public_url,
+        }],
+    })))
+}
+
 async fn describe_server(State(state): State<AppState>) -> Json<DescribeServerResp> {
     Json(DescribeServerResp {
-        did: "did:web:pds.maarcadetweet.local".into(),
+        // Derived from `PDS_PUBLIC_URL`, never hardcoded — see
+        // `AppConfig::pds_did`. The same value ids the document at
+        // `/.well-known/did.json`.
+        did: state.cfg.pds_did(),
         available_user_domains: vec![state
             .cfg
             .pds_handle_dns_zone

crates/pds-server/tests/pds_integration.rs

@@ -38,11 +38,86 @@ async fn describe_server() {
         .json()
         .await
         .unwrap();
-    assert!(r["did"].is_string());
+    // The DID is derived from `PDS_PUBLIC_URL`, not hardcoded — so we
+    // assert the *shape* (any deployment must produce a did:web) and
+    // leave the exact value to `at_shared::config`'s unit tests.
+    let did = r["did"].as_str().expect("describeServer must return a did");
+    assert!(did.starts_with("did:web:"), "did = {did}");
     assert!(r["available_user_domains"].is_array());
     assert_eq!(r["invite_code_required"], json!(false));
 }
 
+/// `GET /.well-known/did.json` — the document the AppView fetches to
+/// learn the key our access tokens are signed with.
+///
+/// Two properties matter beyond "it returns JSON": the document's `id`
+/// must be the same DID `describeServer` advertises (otherwise a client
+/// that trusts one and resolves the other ends up at a different
+/// identity), and it must carry a usable `publicKeyMultibase`.
+#[tokio::test]
+async fn did_document_publishes_the_server_key() {
+    if !wait_for_pds().await {
+        eprintln!("pds not running, skipping");
+        return;
+    }
+    let c = client().await;
+    let doc: Value = c
+        .get(format!("{}/.well-known/did.json", PDS_URL))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+
+    let id = doc["id"].as_str().expect("did document needs an id");
+    assert!(id.starts_with("did:web:"), "id = {id}");
+
+    let described: Value = c
+        .get(format!("{}/xrpc/com.atproto.server.describeServer", PDS_URL))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(
+        described["did"].as_str().unwrap(),
+        id,
+        "describeServer and the did document must name the same identity"
+    );
+
+    let vm = &doc["verificationMethod"][0];
+    assert_eq!(vm["type"], json!("Multikey"));
+    assert_eq!(vm["controller"], json!(id));
+    assert_eq!(vm["id"], json!(format!("{id}#atproto")));
+    let key = vm["publicKeyMultibase"]
+        .as_str()
+        .expect("verificationMethod needs publicKeyMultibase");
+    // base58-btc multibase — the `z` prefix the AppView's decoder wants.
+    assert!(key.starts_with('z'), "key = {key}");
+
+    // And it really is the key our tokens verify against: mint a
+    // session and check the access JWT against the published key.
+    let handle = format!("didjson_{}.maarcadetweet.local", uuid::Uuid::new_v4().simple());
+    let acc: Value = c
+        .post(format!("{}/xrpc/com.atproto.server.createAccount", PDS_URL))
+        .json(&json!({"handle": handle, "password": "hunter2hunter2"}))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    let jwt = acc["access_jwt"].as_str().expect("access_jwt");
+    let claims = at_crypto::jwt::verify_jwt(jwt, key)
+        .expect("access token must verify against the published key");
+    assert_eq!(claims.sub, acc["did"].as_str().unwrap());
+    assert_eq!(claims.scope.as_deref(), Some("com.atproto.access"));
+    // `iss` is the same did:web the document identifies.
+    assert_eq!(claims.iss, id);
+}
+
 #[tokio::test]
 async fn create_account_session_refresh_resolve() {
     if !wait_for_pds().await {
@@ -758,8 +833,14 @@ async fn sync_list_repos_includes_recent_user() {
         return;
     }
     let (c, did, _jwt, _cids) = fresh_user_with_records().await;
-    // Page through listRepos with a small limit until we see our DID.
+    // Page through listRepos until we see our DID. Start the cursor
-    let mut cursor: Option<String> = None;
+    // immediately *below* the target rather than at the beginning of
+    // the table: `repos` grows without bound on a long-lived dev
+    // instance (a few thousand rows already), and scanning from the
+    // top made this test fail purely because the DID sorted past the
+    // iteration cap. Anchoring at the DID keeps the cursor round trip
+    // under test while staying independent of table size.
+    let mut cursor: Option<String> = Some(did_cursor_just_before(&did));
     let mut found = false;
     for _ in 0..50 {
         let url = match &cursor {
@@ -1022,6 +1103,23 @@ fn urlencode(s: &str) -> String {
         .collect()
 }
 
+/// The immediate keyset predecessor of `did`: the same string with
+/// its last byte decremented. `listRepos` filters with `did > cursor`,
+/// so paging from here puts `did` on the first page regardless of how
+/// many repos precede it in the table. Unlike [`did_cursor_lt`] — which
+/// decrements the *first* byte and therefore lands before every
+/// `did:...` — this stays adjacent to the target.
+///
+/// DIDs are ASCII (`did:plc:` + base32), so byte surgery is safe here.
+fn did_cursor_just_before(did: &str) -> String {
+    let mut bytes = did.as_bytes().to_vec();
+    match bytes.last_mut() {
+        Some(b) if *b > 0 => *b -= 1,
+        _ => return did.to_string(),
+    }
+    String::from_utf8(bytes).unwrap_or_else(|_| did.to_string())
+}
+
 fn did_cursor_lt(did: &str) -> String {
     let bytes = did.as_bytes();
     let mut prefix = Vec::with_capacity(bytes.len());

crates/tauri-app/src-tauri/src/appview_client.rs

@@ -1,8 +1,30 @@
 //! Thin HTTP client the Tauri commands use to talk to the AppView.
 //!
-//! All four methods return parsed JSON or a stringified error that the
+//! Every method returns parsed JSON or a stringified error that the
 //! Tauri command layer surfaces to the Svelte frontend as the
 //! `Result::Err` payload.
+//!
+//! # Authentication
+//!
+//! The AppView's *viewer-scoped* endpoints require the account's access
+//! JWT in an `Authorization: Bearer` header, and additionally check that
+//! the token's `sub` equals the `did` query parameter:
+//!
+//!   * `GET  /api/timeline/home`
+//!   * `GET  /api/notifications`
+//!   * `GET  /api/notifications/count`
+//!   * `POST /api/notifications/seen`
+//!
+//! Those four methods therefore take an `access_jwt` argument (last, the
+//! same position `pds_client.rs` uses). Everything else —
+//! `/api/profile*`, `/api/search`, `/api/post/{uri}`, `/api/thread`,
+//! `/api/followers`, `/api/following` — stays public and deliberately
+//! sends no token, so the read-only views keep working while logged out.
+//!
+//! On an auth failure the AppView answers `401` with
+//! `{"error":"AuthMissing"|"TokenInvalid","message":…}` or `403` with
+//! `{"error":"Forbidden",…}`. See [`status_error`] for why the response
+//! body must survive into the error message.
 
 use anyhow::{anyhow, Context, Result};
 use reqwest::Client;
@@ -58,9 +80,10 @@ pub struct SearchResponse {
 ///
 /// `like_count` and `repost_count` are included when the server
 /// resolves a real post; they're `None` for the "not in index"
-/// sentinel response (where `post` is null). The AppView has no
+/// sentinel response (where `post` is null). `/api/post/{uri}` is a
-/// auth yet, so we don't get `viewer_liked` / `viewer_reposted`
+/// public endpoint that takes no token, so there is no viewer to
-/// from the server.
+/// resolve against and we don't get `viewer_liked` /
+/// `viewer_reposted`; [`Self::fetch_thread`] with a `viewer_did` does.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct ThreadResponse {
     pub post: Option<PostDto>,
@@ -77,6 +100,104 @@ pub struct ThreadView {
     pub root: Option<PostDto>,
 }
 
+/// `GET /api/thread?uri=…` response — the *full* thread shape (the
+/// whole ancestor chain plus the direct replies), as opposed to the
+/// narrower `{ post, thread: { parent, root } }` of
+/// [`ThreadResponse`]. Both come from the same server-side thread
+/// walk, so they can never disagree about who the parent is.
+///
+/// `parents` is ordered root-first, `replies` oldest-first. The
+/// `viewer_*` flags are only populated when a `viewer_did` was passed;
+/// `None` means "unknown", not "false".
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ThreadFullResponse {
+    pub post: Option<PostDto>,
+    #[serde(default)]
+    pub parents: Vec<PostDto>,
+    #[serde(default)]
+    pub root: Option<PostDto>,
+    #[serde(default)]
+    pub replies: Vec<PostDto>,
+    #[serde(default)]
+    pub like_count: Option<i64>,
+    #[serde(default)]
+    pub repost_count: Option<i64>,
+    #[serde(default)]
+    pub viewer_liked: Option<bool>,
+    #[serde(default)]
+    pub viewer_reposted: Option<bool>,
+}
+
+/// One hydrated row of `GET /api/notifications`.
+///
+/// `kind` is `"like" | "repost" | "follow" | "reply"` — kept as a
+/// `String` rather than an enum so an unknown kind added server-side
+/// deserialises instead of failing the whole page; the frontend has
+/// the same fallback.
+///
+/// `read_at` is `None` while the notification is unread — that's the
+/// state the tray badge keys off.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct NotificationDto {
+    pub id: i64,
+    pub kind: String,
+    pub author_did: String,
+    pub author_handle: String,
+    #[serde(default)]
+    pub author_display_name: Option<String>,
+    #[serde(default)]
+    pub author_avatar_cid: Option<String>,
+    /// `null` for `"follow"`; the recipient's own post for
+    /// `"like"`/`"repost"`; the reply itself for `"reply"`.
+    #[serde(default)]
+    pub subject_uri: Option<String>,
+    #[serde(default)]
+    pub subject_text: Option<String>,
+    pub created_at: String,
+    /// The list's sort key, and the value the client echoes back as
+    /// `seen_at` when marking the page read.
+    pub indexed_at: String,
+    #[serde(default)]
+    pub read_at: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct NotificationsResponse {
+    pub notifications: Vec<NotificationDto>,
+    pub cursor: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct NotificationCountResponse {
+    pub count: i64,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct NotificationSeenResponse {
+    pub ok: bool,
+    pub updated: i64,
+}
+
+/// A minimal profile card as returned by `GET /api/followers` and
+/// `GET /api/following`. Deliberately not [`ProfileResponse`] — a page
+/// of 30 followers would otherwise be 30 post queries server-side.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ActorProfileDto {
+    pub did: String,
+    /// Without a leading `@` (the UI renders `@{handle}`).
+    pub handle: String,
+    #[serde(default)]
+    pub display_name: Option<String>,
+    #[serde(default)]
+    pub avatar_cid: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ActorListResponse {
+    pub profiles: Vec<ActorProfileDto>,
+    pub cursor: Option<String>,
+}
+
 #[derive(Clone)]
 pub struct AppViewClient {
     pub base_url: String,
@@ -94,16 +215,22 @@ impl AppViewClient {
         }
     }
 
-    /// `GET /api/timeline/home?did=&limit=&cursor=`
+    /// `GET /api/timeline/home?did=&limit=&cursor=` — **authenticated**.
+    ///
+    /// `access_jwt` goes out as `Authorization: Bearer`; the AppView
+    /// rejects the call with 401 without it and with 403 when the
+    /// token's `sub` doesn't match `did`.
     pub async fn fetch_timeline(
         &self,
         did: &str,
         cursor: Option<&str>,
         limit: u32,
+        access_jwt: &str,
     ) -> Result<TimelineResponse> {
         let mut req = self
             .client
             .get(format!("{}/api/timeline/home", self.base_url))
+            .bearer_auth(access_jwt)
             .query(&[("did", did), ("limit", &limit.to_string())]);
         if let Some(c) = cursor {
             req = req.query(&[("cursor", c)]);
@@ -113,13 +240,7 @@ impl AppViewClient {
             .await
             .context("appview: failed to send timeline request")?;
         if !resp.status().is_success() {
-            let status = resp.status();
+            return Err(status_error("timeline home", resp).await);
-            let body = resp.text().await.unwrap_or_default();
-            return Err(anyhow!(
-                "appview: timeline home returned {}: {}",
-                status,
-                body
-            ));
         }
         resp
             .json::<TimelineResponse>()
@@ -146,13 +267,7 @@ impl AppViewClient {
             .await
             .context("appview: failed to send profile request")?;
         if !resp.status().is_success() {
-            let status = resp.status();
+            return Err(status_error("profile", resp).await);
-            let body = resp.text().await.unwrap_or_default();
-            return Err(anyhow!(
-                "appview: profile returned {}: {}",
-                status,
-                body
-            ));
         }
         resp
             .json::<ProfileResponse>()
@@ -170,13 +285,7 @@ impl AppViewClient {
             .await
             .context("appview: failed to send profile-by-did request")?;
         if !resp.status().is_success() {
-            let status = resp.status();
+            return Err(status_error("profile-by-did", resp).await);
-            let body = resp.text().await.unwrap_or_default();
-            return Err(anyhow!(
-                "appview: profile-by-did returned {}: {}",
-                status,
-                body
-            ));
         }
         resp
             .json::<ProfileResponse>()
@@ -194,13 +303,7 @@ impl AppViewClient {
             .await
             .context("appview: failed to send search request")?;
         if !resp.status().is_success() {
-            let status = resp.status();
+            return Err(status_error("search", resp).await);
-            let body = resp.text().await.unwrap_or_default();
-            return Err(anyhow!(
-                "appview: search returned {}: {}",
-                status,
-                body
-            ));
         }
         resp
             .json::<SearchResponse>()
@@ -225,19 +328,215 @@ impl AppViewClient {
             .await
             .context("appview: failed to send post request")?;
         if !resp.status().is_success() {
-            let status = resp.status();
+            return Err(status_error("post", resp).await);
-            let body = resp.text().await.unwrap_or_default();
-            return Err(anyhow!(
-                "appview: post returned {}: {}",
-                status,
-                body
-            ));
         }
         resp
             .json::<ThreadResponse>()
             .await
             .context("appview: post JSON parse")
     }
+
+    /// `GET /api/thread?uri=…&viewer_did=…` — the full thread: the
+    /// whole ancestor chain (root first) plus the direct replies
+    /// (oldest first).
+    ///
+    /// We use the query-param spelling rather than
+    /// `/api/thread/<uri>` because the `at://` URI survives a
+    /// query-string round trip without the manual percent-encoding
+    /// [`Self::fetch_post`] needs — `reqwest`'s `.query()` does the
+    /// escaping itself.
+    pub async fn fetch_thread(
+        &self,
+        uri: &str,
+        viewer_did: Option<&str>,
+    ) -> Result<ThreadFullResponse> {
+        let mut req = self
+            .client
+            .get(format!("{}/api/thread", self.base_url))
+            .query(&[("uri", uri)]);
+        if let Some(v) = viewer_did {
+            req = req.query(&[("viewer_did", v)]);
+        }
+        let resp = req
+            .send()
+            .await
+            .context("appview: failed to send thread request")?;
+        if !resp.status().is_success() {
+            return Err(status_error("thread", resp).await);
+        }
+        resp
+            .json::<ThreadFullResponse>()
+            .await
+            .context("appview: thread JSON parse")
+    }
+
+    /// `GET /api/notifications?did=&limit=&cursor=` — **authenticated**;
+    /// newest first, same opaque-cursor pagination contract as the
+    /// timeline.
+    pub async fn fetch_notifications(
+        &self,
+        did: &str,
+        cursor: Option<&str>,
+        limit: u32,
+        access_jwt: &str,
+    ) -> Result<NotificationsResponse> {
+        let mut req = self
+            .client
+            .get(format!("{}/api/notifications", self.base_url))
+            .bearer_auth(access_jwt)
+            .query(&[("did", did), ("limit", &limit.to_string())]);
+        if let Some(c) = cursor {
+            req = req.query(&[("cursor", c)]);
+        }
+        let resp = req
+            .send()
+            .await
+            .context("appview: failed to send notifications request")?;
+        if !resp.status().is_success() {
+            return Err(status_error("notifications", resp).await);
+        }
+        resp
+            .json::<NotificationsResponse>()
+            .await
+            .context("appview: notifications JSON parse")
+    }
+
+    /// `GET /api/notifications/count?did=` — **authenticated**; unread
+    /// count for the NavRail badge. Cheap enough to poll (partial index
+    /// on the server side).
+    pub async fn notification_count(
+        &self,
+        did: &str,
+        access_jwt: &str,
+    ) -> Result<NotificationCountResponse> {
+        let resp = self
+            .client
+            .get(format!("{}/api/notifications/count", self.base_url))
+            .bearer_auth(access_jwt)
+            .query(&[("did", did)])
+            .send()
+            .await
+            .context("appview: failed to send notification-count request")?;
+        if !resp.status().is_success() {
+            return Err(status_error("notification count", resp).await);
+        }
+        resp
+            .json::<NotificationCountResponse>()
+            .await
+            .context("appview: notification count JSON parse")
+    }
+
+    /// `POST /api/notifications/seen` — **authenticated**; mark
+    /// everything indexed at or before `seen_at` as read. Passing `None`
+    /// marks *all* currently unread rows. Idempotent; a second call
+    /// reports `updated: 0`.
+    ///
+    /// The server accepts both `seenAt` and `seen_at`; we send the
+    /// camelCase spelling because that's what the wire contract
+    /// documents.
+    pub async fn mark_notifications_seen(
+        &self,
+        did: &str,
+        seen_at: Option<&str>,
+        access_jwt: &str,
+    ) -> Result<NotificationSeenResponse> {
+        let mut body = serde_json::json!({ "did": did });
+        if let Some(ts) = seen_at {
+            body["seenAt"] = Value::String(ts.to_string());
+        }
+        let resp = self
+            .client
+            .post(format!("{}/api/notifications/seen", self.base_url))
+            .bearer_auth(access_jwt)
+            .json(&body)
+            .send()
+            .await
+            .context("appview: failed to send notifications-seen request")?;
+        if !resp.status().is_success() {
+            return Err(status_error("notifications seen", resp).await);
+        }
+        resp
+            .json::<NotificationSeenResponse>()
+            .await
+            .context("appview: notifications seen JSON parse")
+    }
+
+    /// `GET /api/followers?did=&limit=&cursor=`
+    pub async fn fetch_followers(
+        &self,
+        did: &str,
+        cursor: Option<&str>,
+        limit: u32,
+    ) -> Result<ActorListResponse> {
+        self.actor_list("followers", did, cursor, limit).await
+    }
+
+    /// `GET /api/following?did=&limit=&cursor=`
+    pub async fn fetch_following(
+        &self,
+        did: &str,
+        cursor: Option<&str>,
+        limit: u32,
+    ) -> Result<ActorListResponse> {
+        self.actor_list("following", did, cursor, limit).await
+    }
+
+    /// Shared body of [`Self::fetch_followers`] and
+    /// [`Self::fetch_following`] — the two endpoints have an identical
+    /// request and response shape and differ only in the path segment.
+    async fn actor_list(
+        &self,
+        path: &str,
+        did: &str,
+        cursor: Option<&str>,
+        limit: u32,
+    ) -> Result<ActorListResponse> {
+        let mut req = self
+            .client
+            .get(format!("{}/api/{}", self.base_url, path))
+            .query(&[("did", did), ("limit", &limit.to_string())]);
+        if let Some(c) = cursor {
+            req = req.query(&[("cursor", c)]);
+        }
+        let resp = req
+            .send()
+            .await
+            .with_context(|| format!("appview: failed to send {path} request"))?;
+        if !resp.status().is_success() {
+            return Err(status_error(path, resp).await);
+        }
+        resp
+            .json::<ActorListResponse>()
+            .await
+            .with_context(|| format!("appview: {path} JSON parse"))
+    }
+}
+
+/// Turn a non-2xx AppView response into an `anyhow::Error` whose
+/// message carries the server's response body **verbatim**.
+///
+/// Keeping the body is load-bearing, not cosmetic. The AppView answers
+/// an expired or malformed access token with
+/// `401 {"error":"TokenInvalid","message":…}`, and the frontend's
+/// `safeInvoke` (`src/lib/api/client.ts`) decides whether to refresh the
+/// session and retry by sniffing the *stringified* Rust error for the
+/// literal substring `"TokenInvalid"` (or `"ExpiredSignature"`). The
+/// chain is therefore:
+///
+/// ```text
+/// AppView 401 body ──► status_error() ──► anyhow msg
+///   ──► lib.rs `.map_err(|e| e.to_string())` ──► Tauri IPC reject
+///   ──► safeInvoke's isTokenInvalid() ──► auth_refresh + retry once
+/// ```
+///
+/// Every link is a plain string, so swallowing the body here (e.g.
+/// formatting only the status code) silently breaks token renewal —
+/// the user's timeline just stops updating an hour after login. The
+/// unit tests below pin the substring so that can't regress.
+async fn status_error(label: &str, resp: reqwest::Response) -> anyhow::Error {
+    let status = resp.status();
+    let body = resp.text().await.unwrap_or_default();
+    anyhow!("appview: {} returned {}: {}", label, status, body)
 }
 
 /// Percent-encode every byte of `s` for use as a URL path segment.
@@ -265,6 +564,9 @@ fn percent_encode_path(s: &str) -> String {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::sync::{Arc, Mutex};
+    use tokio::io::{AsyncReadExt, AsyncWriteExt};
+    use tokio::net::TcpListener;
 
     #[test]
     fn percent_encode_path_at_uri() {
@@ -275,4 +577,241 @@ mod tests {
             "at%3A%2F%2Fdid%3Aplc%3Aabc%2Fapp.twi.post%2F3k2"
         );
     }
+
+    // -- mock AppView -------------------------------------------------
+    //
+    // A ~40-line HTTP/1.1 server on an ephemeral port, rather than a
+    // mocking crate, so the test adds no dependency to a workspace that
+    // currently has none for this. It answers every request with a
+    // canned status + body and records each request head so the tests
+    // can assert on the `Authorization` header we did (or deliberately
+    // did not) send.
+
+    /// The raw request heads (request line + header block) the mock saw,
+    /// in arrival order.
+    type Recorded = Arc<Mutex<Vec<String>>>;
+
+    /// Byte offset of the `\r\n\r\n` that ends the header block.
+    fn headers_end(buf: &[u8]) -> Option<usize> {
+        buf.windows(4).position(|w| w == b"\r\n\r\n")
+    }
+
+    /// Announced body length from a request head, if any. Needed so the
+    /// POST test drains the JSON body before the mock closes the socket
+    /// — closing mid-write would surface to `reqwest` as a connection
+    /// error instead of the 401 we're trying to assert on.
+    fn content_length(head: &str) -> usize {
+        head.lines()
+            .find_map(|l| {
+                let (k, v) = l.split_once(':')?;
+                k.trim()
+                    .eq_ignore_ascii_case("content-length")
+                    .then(|| v.trim().parse::<usize>().ok())?
+            })
+            .unwrap_or(0)
+    }
+
+    /// Serve `n` connections, answering each with `status`/`reason` and
+    /// `body`. Returns the base URL to point an [`AppViewClient`] at,
+    /// plus the recording handle.
+    async fn spawn_mock(
+        status: u16,
+        reason: &'static str,
+        body: &'static str,
+        n: usize,
+    ) -> (String, Recorded) {
+        let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+        let addr = listener.local_addr().unwrap();
+        let recorded: Recorded = Arc::new(Mutex::new(Vec::new()));
+        let rec = recorded.clone();
+        tokio::spawn(async move {
+            for _ in 0..n {
+                let Ok((mut sock, _)) = listener.accept().await else {
+                    return;
+                };
+                let mut buf: Vec<u8> = Vec::new();
+                let mut chunk = [0u8; 2048];
+                loop {
+                    let read = match sock.read(&mut chunk).await {
+                        Ok(0) | Err(_) => break,
+                        Ok(k) => k,
+                    };
+                    buf.extend_from_slice(&chunk[..read]);
+                    if let Some(p) = headers_end(&buf) {
+                        let head = String::from_utf8_lossy(&buf[..p]).into_owned();
+                        if buf.len() - (p + 4) >= content_length(&head) {
+                            rec.lock().unwrap().push(head);
+                            break;
+                        }
+                    }
+                }
+                // `connection: close` keeps every request on a fresh
+                // socket, so the recorded order matches the call order.
+                let resp = format!(
+                    "HTTP/1.1 {status} {reason}\r\n\
+                     content-type: application/json\r\n\
+                     content-length: {}\r\n\
+                     connection: close\r\n\r\n{body}",
+                    body.len()
+                );
+                let _ = sock.write_all(resp.as_bytes()).await;
+                let _ = sock.shutdown().await;
+            }
+        });
+        (format!("http://{addr}"), recorded)
+    }
+
+    /// Value of the `Authorization` header in a recorded request head,
+    /// or `None` when the request carried none.
+    fn auth_header(head: &str) -> Option<String> {
+        head.lines().find_map(|l| {
+            let (k, v) = l.split_once(':')?;
+            k.trim()
+                .eq_ignore_ascii_case("authorization")
+                .then(|| v.trim().to_string())
+        })
+    }
+
+    // -- the contract the TS retry chain depends on -------------------
+
+    /// The AppView's 401 body for an expired access token.
+    const TOKEN_INVALID_BODY: &str =
+        r#"{"error":"TokenInvalid","message":"ExpiredSignature"}"#;
+
+    /// **This is the test the token-renewal path hangs off.**
+    ///
+    /// `src/lib/api/client.ts`'s `safeInvoke` refreshes the session and
+    /// retries exactly once when `isTokenInvalid(e)` matches — and that
+    /// predicate is a substring search for `"TokenInvalid"` /
+    /// `"ExpiredSignature"` over the *stringified* error that came up
+    /// from Rust. The AppView only ever states the code in its JSON
+    /// body, so if [`status_error`] were to drop the body (or truncate
+    /// it to the status code) the retry would never fire and the desktop
+    /// client would sit on a dead timeline until the user restarts it.
+    ///
+    /// So: for each of the four authenticated endpoints, assert the code
+    /// survives verbatim all the way into `Error::to_string()` — which
+    /// is exactly what `lib.rs` hands the Tauri IPC layer via
+    /// `.map_err(|e| e.to_string())`.
+    #[tokio::test]
+    async fn token_invalid_code_survives_into_the_error_string() {
+        let (base, _rec) = spawn_mock(401, "Unauthorized", TOKEN_INVALID_BODY, 4).await;
+        let c = AppViewClient::new(base);
+
+        let errs = vec![
+            c.fetch_timeline("did:plc:me", None, 30, "stale")
+                .await
+                .unwrap_err()
+                .to_string(),
+            c.fetch_notifications("did:plc:me", None, 30, "stale")
+                .await
+                .unwrap_err()
+                .to_string(),
+            c.notification_count("did:plc:me", "stale")
+                .await
+                .unwrap_err()
+                .to_string(),
+            c.mark_notifications_seen("did:plc:me", None, "stale")
+                .await
+                .unwrap_err()
+                .to_string(),
+        ];
+
+        for e in &errs {
+            // The literal the TS `isTokenInvalid()` greps for. Both
+            // spellings it accepts are in this body.
+            assert!(
+                e.contains("TokenInvalid"),
+                "error must carry the AppView's code verbatim, got: {e}"
+            );
+            assert!(
+                e.contains("ExpiredSignature"),
+                "error must carry the AppView's message verbatim, got: {e}"
+            );
+            // The status is useful context, but it is NOT what the retry
+            // keys off — asserting it here documents that both travel.
+            assert!(e.contains("401"), "status should travel too, got: {e}");
+        }
+
+        // Each endpoint still labels itself, so a log line says which
+        // call failed.
+        assert!(errs[0].contains("timeline home"));
+        assert!(errs[1].contains("notifications"));
+        assert!(errs[2].contains("notification count"));
+        assert!(errs[3].contains("notifications seen"));
+    }
+
+    /// The 403 the AppView returns when the token is valid but its
+    /// `sub` doesn't match the `did` query parameter. Deliberately
+    /// *not* something `isTokenInvalid` matches: refreshing wouldn't
+    /// help, so the retry must not fire — but the code still has to
+    /// reach the UI so the message is actionable.
+    #[tokio::test]
+    async fn forbidden_body_survives_and_does_not_look_refreshable() {
+        let (base, _rec) = spawn_mock(
+            403,
+            "Forbidden",
+            r#"{"error":"Forbidden","message":"did does not match token subject"}"#,
+            1,
+        )
+        .await;
+        let c = AppViewClient::new(base);
+
+        let e = c
+            .fetch_timeline("did:plc:someone-else", None, 30, "good-jwt")
+            .await
+            .unwrap_err()
+            .to_string();
+
+        assert!(e.contains("Forbidden"), "got: {e}");
+        assert!(e.contains("403"), "got: {e}");
+        assert!(!e.contains("TokenInvalid"));
+        assert!(!e.contains("ExpiredSignature"));
+    }
+
+    /// The four viewer-scoped endpoints must actually put the JWT on
+    /// the wire — an empty or missing header is a 401 from the server.
+    #[tokio::test]
+    async fn authenticated_endpoints_send_the_bearer_header() {
+        let (base, rec) = spawn_mock(500, "Internal Server Error", "{}", 4).await;
+        let c = AppViewClient::new(base);
+
+        let _ = c.fetch_timeline("did:plc:me", None, 30, "jwt-abc").await;
+        let _ = c.fetch_notifications("did:plc:me", None, 30, "jwt-abc").await;
+        let _ = c.notification_count("did:plc:me", "jwt-abc").await;
+        let _ = c
+            .mark_notifications_seen("did:plc:me", Some("2026-09-09T10:00:00Z"), "jwt-abc")
+            .await;
+
+        let heads = rec.lock().unwrap().clone();
+        assert_eq!(heads.len(), 4, "every call should have reached the server");
+        for h in &heads {
+            assert_eq!(
+                auth_header(h).as_deref(),
+                Some("Bearer jwt-abc"),
+                "missing/!= bearer token in:\n{h}"
+            );
+        }
+        // The POST still carries its JSON body alongside the header.
+        assert!(heads[3].starts_with("POST /api/notifications/seen"));
+    }
+
+    /// The public half of the API must keep working while logged out,
+    /// so it must not grow an `Authorization` header by accident.
+    #[tokio::test]
+    async fn public_endpoints_send_no_authorization_header() {
+        let (base, rec) = spawn_mock(200, "OK", r#"{"posts":[],"q":"hi"}"#, 1).await;
+        let c = AppViewClient::new(base);
+        let r = c.fetch_search("hi", 30).await.unwrap();
+        assert_eq!(r.q, "hi");
+        assert!(auth_header(&rec.lock().unwrap()[0]).is_none());
+
+        let (base2, rec2) = spawn_mock(200, "OK", r#"{"profiles":[],"cursor":null}"#, 2).await;
+        let c2 = AppViewClient::new(base2);
+        c2.fetch_followers("did:plc:me", None, 30).await.unwrap();
+        c2.fetch_following("did:plc:me", None, 30).await.unwrap();
+        for h in rec2.lock().unwrap().iter() {
+            assert!(auth_header(h).is_none(), "unexpected auth header in:\n{h}");
+        }
+    }
 }

crates/tauri-app/src-tauri/src/lib.rs

@@ -354,6 +354,28 @@ async fn unfollow_user(
     }))
 }
 
+/// Access JWT for the AppView's viewer-scoped endpoints.
+///
+/// The four authenticated AppView calls (`timeline_home`,
+/// `fetch_notifications`, `notification_count`,
+/// `mark_notifications_seen`) all need the same thing: the stored
+/// session's access JWT, or a message the UI can render when there
+/// isn't one. Factored out so no call site can accidentally send an
+/// empty `Authorization: Bearer` header — which the AppView would
+/// answer with a 401 `TokenInvalid`, and the frontend would then burn a
+/// pointless refresh round trip on before failing anyway.
+///
+/// The message deliberately contains neither `TokenInvalid` nor
+/// `ExpiredSignature`: `safeInvoke`'s `isTokenInvalid()` greps for those
+/// substrings, and a logged-out client has nothing to refresh *with*.
+fn require_access_jwt(state: &AppState, what: &str) -> Result<String, String> {
+    state
+        .store
+        .load()
+        .map(|s| s.access_jwt)
+        .ok_or_else(|| format!("not logged in: {what} requires a signed-in session"))
+}
+
 #[tauri::command]
 async fn timeline_home(
     state: tauri::State<'_, AppState>,
@@ -362,9 +384,10 @@ async fn timeline_home(
     limit: Option<u32>,
 ) -> Result<appview_client::TimelineResponse, String> {
     let lim = limit.unwrap_or(30).clamp(1, 100);
+    let jwt = require_access_jwt(&state, "the home timeline")?;
     state
         .appview
-        .fetch_timeline(&did, cursor.as_deref(), lim)
+        .fetch_timeline(&did, cursor.as_deref(), lim, &jwt)
         .await
         .map_err(|e| e.to_string())
 }
@@ -381,6 +404,29 @@ async fn profile_get(
         .map_err(|e| e.to_string())
 }
 
+/// `profile_get_by_did(did)` — resolve a profile by DID rather than
+/// by handle (`GET /api/profile?did=…`).
+///
+/// This is the *only* correct lookup for an actor that came out of a
+/// notification or a follower list: the AppView synthesises a
+/// placeholder `handle` (a truncated DID, see `short_did_bare`) for
+/// actors it has neither a `profiles` row nor an indexed post for, and
+/// feeding that placeholder back into the handle lookup matches
+/// nothing — `resolve_profile` then answers with a synthetic empty
+/// profile. The DID in the notification / actor DTO is real, so we
+/// navigate by that instead.
+#[tauri::command]
+async fn profile_get_by_did(
+    state: tauri::State<'_, AppState>,
+    did: String,
+) -> Result<appview_client::ProfileResponse, String> {
+    state
+        .appview
+        .fetch_profile_by_did(&did)
+        .await
+        .map_err(|e| e.to_string())
+}
+
 #[tauri::command]
 async fn search(
     state: tauri::State<'_, AppState>,
@@ -407,6 +453,111 @@ async fn post_get(
         .map_err(|e| e.to_string())
 }
 
+/// `fetch_thread(uri, viewer_did?)` — the full thread around `uri`:
+/// the whole ancestor chain (root first) plus the direct replies
+/// (oldest first). `post_get` stays the narrower two-hop shape the
+/// timeline's inline thread modal uses; this is what a dedicated
+/// thread view wants.
+#[tauri::command]
+async fn fetch_thread(
+    state: tauri::State<'_, AppState>,
+    uri: String,
+    viewer_did: Option<String>,
+) -> Result<appview_client::ThreadFullResponse, String> {
+    state
+        .appview
+        .fetch_thread(&uri, viewer_did.as_deref())
+        .await
+        .map_err(|e| e.to_string())
+}
+
+/// `fetch_notifications(did, cursor?, limit?)` — one page of the
+/// recipient's notifications, newest first. Same limit clamp as
+/// `timeline_home` (the server clamps too, but doing it here means a
+/// bad `limit` never costs a round trip).
+#[tauri::command]
+async fn fetch_notifications(
+    state: tauri::State<'_, AppState>,
+    did: String,
+    cursor: Option<String>,
+    limit: Option<u32>,
+) -> Result<appview_client::NotificationsResponse, String> {
+    let lim = limit.unwrap_or(30).clamp(1, 100);
+    let jwt = require_access_jwt(&state, "notifications")?;
+    state
+        .appview
+        .fetch_notifications(&did, cursor.as_deref(), lim, &jwt)
+        .await
+        .map_err(|e| e.to_string())
+}
+
+/// `notification_count(did)` — unread count for the NavRail badge.
+#[tauri::command]
+async fn notification_count(
+    state: tauri::State<'_, AppState>,
+    did: String,
+) -> Result<appview_client::NotificationCountResponse, String> {
+    let jwt = require_access_jwt(&state, "the unread-notification count")?;
+    state
+        .appview
+        .notification_count(&did, &jwt)
+        .await
+        .map_err(|e| e.to_string())
+}
+
+/// `mark_notifications_seen(did, seen_at?)` — mark every notification
+/// indexed at or before `seen_at` as read. The frontend passes the
+/// `indexed_at` of the topmost row it actually rendered, so a
+/// notification that lands mid-scroll is never silently swallowed.
+/// Omitting `seen_at` marks everything currently unread.
+#[tauri::command]
+async fn mark_notifications_seen(
+    state: tauri::State<'_, AppState>,
+    did: String,
+    seen_at: Option<String>,
+) -> Result<appview_client::NotificationSeenResponse, String> {
+    let jwt = require_access_jwt(&state, "marking notifications seen")?;
+    state
+        .appview
+        .mark_notifications_seen(&did, seen_at.as_deref(), &jwt)
+        .await
+        .map_err(|e| e.to_string())
+}
+
+/// `fetch_followers(did, cursor?, limit?)` — one page of the actors
+/// who follow `did`.
+#[tauri::command]
+async fn fetch_followers(
+    state: tauri::State<'_, AppState>,
+    did: String,
+    cursor: Option<String>,
+    limit: Option<u32>,
+) -> Result<appview_client::ActorListResponse, String> {
+    let lim = limit.unwrap_or(30).clamp(1, 100);
+    state
+        .appview
+        .fetch_followers(&did, cursor.as_deref(), lim)
+        .await
+        .map_err(|e| e.to_string())
+}
+
+/// `fetch_following(did, cursor?, limit?)` — one page of the actors
+/// `did` follows.
+#[tauri::command]
+async fn fetch_following(
+    state: tauri::State<'_, AppState>,
+    did: String,
+    cursor: Option<String>,
+    limit: Option<u32>,
+) -> Result<appview_client::ActorListResponse, String> {
+    let lim = limit.unwrap_or(30).clamp(1, 100);
+    state
+        .appview
+        .fetch_following(&did, cursor.as_deref(), lim)
+        .await
+        .map_err(|e| e.to_string())
+}
+
 #[tauri::command]
 async fn status_pds(state: tauri::State<'_, AppState>) -> Result<serde_json::Value, String> {
     let sess = state.store.load();
@@ -791,8 +942,15 @@ pub fn run() {
             resolve_handle,
             timeline_home,
             profile_get,
+            profile_get_by_did,
             search,
             post_get,
+            fetch_thread,
+            fetch_notifications,
+            notification_count,
+            mark_notifications_seen,
+            fetch_followers,
+            fetch_following,
             like_post,
             unlike_post,
             repost_post,

crates/tauri-app/src-tauri/tauri.conf.json

@@ -40,7 +40,7 @@
         "https://releases.maarcadetweet.local/{{target}}/{{arch}}/{{current_version}}"
       ],
       "pubkey": "",
-      "_comment": "Auto-update is disabled for dev. To enable for releases: (1) stand up a release-artifacts server that serves update.json, (2) run `tauri signer generate` and paste the pubkey here, (3) flip active+dialog to true. Capabilities already include `updater:default` so the frontend can request update checks via the plugin once enabled."
+      "_comment": "Auto-update is inert in dev: nothing in the app calls the updater's check(), and `pubkey` is empty. Note that `active` and `dialog` above are Tauri v1 leftovers — the v2 updater plugin ignores unknown keys, so they do NOT switch anything on or off. The full production path (signer keys, pubkey, endpoints, bundle.createUpdaterArtifacts, latest.json format, per-platform build + artifact paths, and the still-missing check() call) is documented in docs/tauri-release.md. Enable it via a release config overlay passed to `tauri build --config`, so this dev config stays as is. Capabilities already include `updater:default` (check/download/install)."
     }
   },
   "bundle": {

crates/tauri-app/src/App.svelte

@@ -6,12 +6,16 @@
     fetchTimeline,
     fetchSearch,
     fetchPost,
+    errorMessage,
+    isAuthFailure,
+    notificationCount,
     openExternalUrl,
     showError,
     type Session,
     type Post,
   } from "./lib/api/client";
   import NavRail from "./lib/components/NavRail.svelte";
+  import NotificationsView from "./lib/components/NotificationsView.svelte";
   import StatusBar from "./lib/components/StatusBar.svelte";
   import PostCard from "./lib/components/PostCard.svelte";
   import ComposeBox from "./lib/components/ComposeBox.svelte";
@@ -21,7 +25,14 @@
   import Skeleton from "./lib/components/Skeleton.svelte";
   import Sidebar from "./lib/components/Sidebar.svelte";
 
-  type View = "home" | "compose" | "profile" | "user" | "search" | "settings";
+  type View =
+    | "home"
+    | "notifications"
+    | "compose"
+    | "profile"
+    | "user"
+    | "search"
+    | "settings";
 
   let view: View = $state("home");
   // Handle for the "user" view (i.e. someone else's profile). The
@@ -29,6 +40,13 @@
   // goes there). Selecting a handle (via the PostCard avatar link or
   // a future deep-link) navigates to "user" with `selectedHandle` set.
   let selectedHandle: string = $state("");
+  // DID for the "user" view, when the navigation had one. Set by
+  // `openActor` (notification rows, follower/following lists, the
+  // PostCards inside a profile feed) and cleared by
+  // `openUserProfile` (timeline / search, where only a handle is
+  // available). `<ProfileView>` prefers it over the handle — see the
+  // comment on `openActor`.
+  let selectedDid: string | null = $state(null);
   let currentUser: Session | null = $state(null);
   let status: { did?: string; handle?: string; authenticated: boolean } = $state({ authenticated: false });
 
@@ -40,6 +58,14 @@
   let seenUris: Set<string> = new Set();
   let _statusTimer: number | undefined;
 
+  // Unread-notification badge on the NavRail. Polled on the same 5s
+  // cadence as the timeline refresh (`startPoll`) — the count query is
+  // backed by a partial index server-side, so it's cheap enough to sit
+  // next to the timeline poll rather than needing its own slower
+  // timer. The poll shares `_pollTimer`, so `stopPoll` (logout /
+  // unmount) tears both down in one place.
+  let unreadCount: number = $state(0);
+
   // Home tab strip — "for you" is a placeholder (no real algo yet),
   // "following" is the live behavior. Mirrors the X-style "For you /
   // Following" tabs.
@@ -116,11 +142,44 @@
   }
 
   /// Navigate to the "user" profile view for `handle`. Called from
-  /// `<PostCard on_handle_click>` and the avatar/handle buttons in
+  /// `<PostCard on_handle_click>` on the timeline / search results and
-  /// the post header. The actual profile fetch happens inside
+  /// the avatar/handle buttons in the post header. The actual profile
-  /// `<ProfileView>` on mount.
+  /// fetch happens inside `<ProfileView>`.
+  ///
+  /// Handle-only path: those handles come from `posts.handle`, which
+  /// the AppView resolves from the record itself. Where a DID is
+  /// available, prefer [`openActor`].
   function openUserProfile(handle: string) {
     selectedHandle = handle;
+    selectedDid = null;
+    view = "user";
+    threadRoot = null;
+    threadParent = null;
+  }
+
+  /// Navigate to a profile by DID, with `handle` carried along only as
+  /// a label for the header while the fetch is in flight.
+  ///
+  /// This is the path every actor coming out of a notification or a
+  /// follower/following list must take. The AppView synthesises a
+  /// placeholder `handle` for actors it has neither a `profiles` row
+  /// nor an indexed post for — a truncated DID like `"did:plc:f5…"`
+  /// (`short_did_bare` in the AppView's `routes.rs`). Feeding that
+  /// back into the handle lookup matches nothing, and the server
+  /// answers with a synthetic empty profile instead of an error, so
+  /// the click reads as a dead end rather than as a failure. The DID
+  /// on the DTO is always real.
+  ///
+  /// We deliberately do NOT sniff the handle for the `…` placeholder
+  /// marker: that would bake the server's current display format into
+  /// the client. Passing the DID explicitly keeps the path correct
+  /// whatever the placeholder ends up looking like.
+  function openActor(did: string, handle: string) {
+    selectedHandle = handle;
+    // An empty DID would resolve to the "did is required" 400; fall
+    // back to the handle lookup in that case rather than guaranteeing
+    // an error.
+    selectedDid = did || null;
     view = "user";
     threadRoot = null;
     threadParent = null;
@@ -302,14 +361,57 @@
   let _pollTimer: number | undefined;
   function startPoll() {
     if (_pollTimer != null) return;
+    // Prime the badge immediately — otherwise a freshly logged-in
+    // user stares at a blank rail for a full interval.
+    void refreshUnreadCount();
     _pollTimer = window.setInterval(() => {
       if (view === "home") void refreshTimeline(false);
+      void refreshUnreadCount();
     }, 5000);
   }
   function stopPoll() {
     if (_pollTimer == null) return;
     window.clearInterval(_pollTimer);
     _pollTimer = undefined;
+    unreadCount = 0;
+  }
+
+  /// Pull the unread count for the NavRail badge. Swallows errors:
+  /// the badge is ambient information, and a transient AppView hiccup
+  /// shouldn't produce a toast every 5 seconds.
+  ///
+  /// One class of error is *not* swallowed-and-retried, though. Since
+  /// the AppView started requiring the access JWT on
+  /// `/api/notifications/count`, a rejected token surfaces here — and
+  /// by the time it does, `safeInvoke` has already spent its one
+  /// automatic refresh. Retrying on a 5s timer would then be a request
+  /// loop against a server that keeps answering 401/403 for as long as
+  /// the app is open. So an auth failure stops the poll outright; the
+  /// next successful login restarts it via the `session.subscribe`
+  /// handler in `onMount`.
+  async function refreshUnreadCount() {
+    if (!currentUser) return;
+    // While the notifications view is open the user is by definition
+    // reading them; the view marks the page seen itself and calls
+    // back into `onNotificationsSeen`. Polling on top of that would
+    // race the ack and flicker the badge back on.
+    if (view === "notifications") return;
+    try {
+      unreadCount = await notificationCount(currentUser.did);
+    } catch (e) {
+      if (isAuthFailure(e)) {
+        console.warn("notification poll stopped: session rejected", e);
+        stopPoll();
+        return;
+      }
+      /* otherwise ignore — keep the last known count */
+    }
+  }
+
+  /// Called by `<NotificationsView on_seen>` once it has acked the
+  /// first page. Zeroes the badge without waiting for the next poll.
+  function onNotificationsSeen() {
+    unreadCount = 0;
   }
 
   async function refreshTimeline(reset: boolean) {
@@ -335,7 +437,7 @@
         if (fresh.length > 0) userPosts = [...fresh, ...userPosts];
       }
     } catch (e) {
-      timelineError = String(e);
+      timelineError = errorMessage(e);
       // Keep whatever we had on a transient failure.
     } finally {
       timelineLoading = false;
@@ -355,7 +457,7 @@
       }
       timelineCursor = r.cursor;
     } catch (e) {
-      timelineError = String(e);
+      timelineError = errorMessage(e);
     } finally {
       timelineLoading = false;
     }
@@ -457,6 +559,35 @@
   }
 </script>
 
+<!--
+  Thread overlay. Defined once as a snippet because two views open a
+  thread through the same `openThread` helper — the timeline (a
+  PostCard's thread button) and the notifications list (a row with a
+  `subject_uri`). Rendering it twice from one definition keeps the
+  close button, the loading skeleton and the parent/root layout from
+  drifting apart.
+-->
+{#snippet threadModal()}
+  {#if threadRoot || threadLoading || threadError}
+    <div class="thread-modal">
+      <header class="thread-modal__head">
+        <span class="crumb">// thread</span>
+        <button class="btn--ghost" onclick={closeThread}>close</button>
+      </header>
+      {#if threadLoading}
+        <Skeleton rows={2} />
+      {:else if threadError}
+        <div class="toast toast--err">err: {threadError}</div>
+      {:else if threadRoot}
+        {#if threadParent && threadParent.uri !== threadRoot.uri}
+          <div class="thread-parent"><PostCard post={threadParent} on_handle_click={openUserProfile} on_reply={onReply} /></div>
+        {/if}
+        <PostCard post={threadRoot} on_handle_click={openUserProfile} on_reply={onReply} />
+      {/if}
+    </div>
+  {/if}
+{/snippet}
+
 {#if !currentUser}
   <div class="login-wrap">
     <LoginScreen
@@ -470,6 +601,7 @@
   <div class="shell">
     <NavRail
       {view}
+      unread={unreadCount}
       on_select={(v) => setView(v)}
     />
     <div class="main">
@@ -504,24 +636,7 @@
           {:else if userPosts.length === 0}
             <div class="empty">// timeline is empty. compose your first post →</div>
           {:else}
-            {#if threadRoot}
+            {@render threadModal()}
-              <div class="thread-modal">
-                <header class="thread-modal__head">
-                  <span class="crumb">// thread</span>
-                  <button class="btn--ghost" onclick={closeThread}>close</button>
-                </header>
-                {#if threadLoading}
-                  <Skeleton rows={2} />
-                {:else if threadError}
-                  <div class="toast toast--err">err: {threadError}</div>
-                {:else if threadRoot}
-                  {#if threadParent && threadParent.uri !== threadRoot.uri}
-                    <div class="thread-parent"><PostCard post={threadParent} on_handle_click={openUserProfile} on_reply={onReply} /></div>
-                  {/if}
-                  <PostCard post={threadRoot} on_handle_click={openUserProfile} on_reply={onReply} />
-                {/if}
-              </div>
-            {/if}
             {#each userPosts as p (p.uri)}
               <PostCard post={p} on_thread_click={openThread} on_handle_click={openUserProfile} on_reply={onReply} />
             {/each}
@@ -533,6 +648,22 @@
               </div>
             {/if}
           {/if}
+        {:else if view === "notifications"}
+          <div class="head">
+            <span class="prompt">$</span>
+            <span class="title">// benachrichtigungen —</span>
+            <span class="as">@{currentUser.handle}</span>
+            <span class="meta">
+              {unreadCount > 0 ? `${unreadCount} ungelesen` : "alles gelesen"}
+            </span>
+          </div>
+          {@render threadModal()}
+          <NotificationsView
+            did={currentUser.did}
+            on_thread_click={openThread}
+            on_actor_click={openActor}
+            on_seen={onNotificationsSeen}
+          />
         {:else if view === "compose"}
           <div class="head">
             <span class="prompt">$</span>
@@ -553,7 +684,9 @@
           </div>
           <ProfileView
             handle={selectedHandle}
+            did={selectedDid}
             on_thread_click={openThread}
+            on_actor_click={openActor}
             current_user_did={currentUser?.did ?? null}
           />
         {:else if view === "profile"}
@@ -565,7 +698,9 @@
             </div>
             <ProfileView
               handle={currentUser.handle}
+              did={currentUser.did}
               on_thread_click={openThread}
+              on_actor_click={openActor}
               current_user_did={currentUser.did}
             />
           {/if}

crates/tauri-app/src/lib/api/appview-auth.test.ts

@@ -0,0 +1,394 @@
+// The AppView auth contract, from the client's side.
+//
+// Same setup as `notifications.test.ts`: `@tauri-apps/api/core` is
+// mocked so no Tauri shell is needed, and every assertion is about the
+// exact sequence of commands we hand the Rust IPC layer.
+//
+// What's pinned here:
+//   * the **token-renewal chain** — a `TokenInvalid` coming out of the
+//     AppView (not the PDS) triggers exactly one `auth_refresh` + one
+//     retry, for each of the four now-authenticated endpoints;
+//   * that the chain fires for a **bare string** rejection, which is
+//     what `invoke` actually rejects with for our `Result<T, String>`
+//     commands — the shape the old `typeof e !== "object"` guard
+//     silently skipped;
+//   * that it fires **once**, never in a loop, and not at all when the
+//     refresh itself fails or when the error isn't refreshable;
+//   * that the **public** endpoints still work with no session at all
+//     and never reach for a refresh.
+//
+// The error strings below are verbatim what the Rust side produces:
+// `appview_client.rs`'s `status_error()` formats
+// `"appview: {label} returned {status}: {body}"`, and `lib.rs`
+// stringifies that into the command's `Err(String)`. The Rust test
+// `token_invalid_code_survives_into_the_error_string` pins the other
+// half of the same contract.
+//
+// Run with:
+//   npx vitest run src/lib/api/appview-auth.test.ts
+
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const invokeMock = vi.fn();
+
+vi.mock("@tauri-apps/api/core", () => ({
+  invoke: (...args: unknown[]) => invokeMock(...args),
+  isTauri: () => true,
+}));
+
+beforeEach(() => {
+  invokeMock.mockReset();
+});
+
+/// Exactly what a Tauri command rejects with once the AppView has
+/// refused an expired access token: a bare string, because our
+/// commands are `Result<T, String>` and `invoke` rejects with the
+/// deserialised payload — not an `Error`.
+function appviewTokenInvalid(label: string): string {
+  return (
+    `appview: ${label} returned 401 Unauthorized: ` +
+    `{"error":"TokenInvalid","message":"ExpiredSignature"}`
+  );
+}
+
+const FRESH_SESSION = {
+  did: "did:plc:me",
+  handle: "me.test",
+  access_jwt: "fresh-access",
+  refresh_jwt: "fresh-refresh",
+};
+
+/// The four endpoints that grew an auth guard, each with the command
+/// name the Rust side registers, the AppView's label in the error
+/// string, a caller, and the payload the retry should resolve with.
+const AUTHED = [
+  {
+    name: "timeline_home",
+    label: "timeline home",
+    payload: { posts: [], cursor: null },
+    call: async () => {
+      const { fetchTimeline } = await import("./client");
+      return fetchTimeline("did:plc:me");
+    },
+  },
+  {
+    name: "fetch_notifications",
+    label: "notifications",
+    payload: { notifications: [], cursor: null },
+    call: async () => {
+      const { fetchNotifications } = await import("./client");
+      return fetchNotifications("did:plc:me");
+    },
+  },
+  {
+    name: "notification_count",
+    label: "notification count",
+    payload: { count: 3 },
+    call: async () => {
+      const { notificationCount } = await import("./client");
+      return notificationCount("did:plc:me");
+    },
+  },
+  {
+    name: "mark_notifications_seen",
+    label: "notifications seen",
+    payload: { ok: true, updated: 2 },
+    call: async () => {
+      const { markNotificationsSeen } = await import("./client");
+      return markNotificationsSeen("did:plc:me", "2026-09-09T10:00:00Z");
+    },
+  },
+] as const;
+
+describe("AppView token renewal", () => {
+  for (const ep of AUTHED) {
+    it(`${ep.name}: a TokenInvalid from the AppView refreshes and retries once`, async () => {
+      invokeMock
+        // 1. the call, rejected by the AppView's auth guard
+        .mockRejectedValueOnce(appviewTokenInvalid(ep.label))
+        // 2. auth_refresh mints a new access JWT from the refresh JWT
+        .mockResolvedValueOnce(FRESH_SESSION)
+        // 3. the same call again, now with the fresh token
+        .mockResolvedValueOnce(ep.payload);
+
+      await expect(ep.call()).resolves.toBeDefined();
+
+      expect(invokeMock.mock.calls.map((c) => c[0])).toEqual([
+        ep.name,
+        "auth_refresh",
+        ep.name,
+      ]);
+      // The retry must repeat the *same* argument bag — a dropped
+      // cursor or limit here would silently change what the user sees.
+      expect(invokeMock.mock.calls[0][1]).toEqual(invokeMock.mock.calls[2][1]);
+    });
+  }
+
+  it("returns the retry's payload, not the failed first attempt", async () => {
+    const { notificationCount } = await import("./client");
+    invokeMock
+      .mockRejectedValueOnce(appviewTokenInvalid("notification count"))
+      .mockResolvedValueOnce(FRESH_SESSION)
+      .mockResolvedValueOnce({ count: 7 });
+
+    await expect(notificationCount("did:plc:me")).resolves.toBe(7);
+  });
+
+  it("fires for a bare-string rejection — the shape Tauri actually uses", async () => {
+    // Regression guard. `invoke` rejects with the deserialised
+    // `Err(String)` payload, i.e. a primitive string. A guard that
+    // bails on anything that isn't an object never sees the code and
+    // the retry silently never runs — the user's timeline just dies an
+    // hour after login with no error anyone would connect to auth.
+    const { fetchTimeline } = await import("./client");
+    invokeMock
+      .mockRejectedValueOnce(appviewTokenInvalid("timeline home"))
+      .mockResolvedValueOnce(FRESH_SESSION)
+      .mockResolvedValueOnce({ posts: [], cursor: null });
+
+    await expect(fetchTimeline("did:plc:me")).resolves.toEqual({
+      posts: [],
+      cursor: null,
+    });
+    expect(invokeMock).toHaveBeenCalledTimes(3);
+  });
+
+  it("also fires when the error arrives as an Error object", async () => {
+    const { fetchTimeline } = await import("./client");
+    invokeMock
+      .mockRejectedValueOnce(new Error(appviewTokenInvalid("timeline home")))
+      .mockResolvedValueOnce(FRESH_SESSION)
+      .mockResolvedValueOnce({ posts: [], cursor: null });
+
+    await expect(fetchTimeline("did:plc:me")).resolves.toBeDefined();
+    expect(invokeMock).toHaveBeenCalledTimes(3);
+  });
+
+  it("retries exactly once — a still-failing retry is not refreshed again", async () => {
+    const { fetchNotifications } = await import("./client");
+    invokeMock
+      .mockRejectedValueOnce(appviewTokenInvalid("notifications"))
+      .mockResolvedValueOnce(FRESH_SESSION)
+      .mockRejectedValueOnce(appviewTokenInvalid("notifications"));
+
+    await expect(fetchNotifications("did:plc:me")).rejects.toThrow(
+      /TokenInvalid/,
+    );
+    // Three calls, not five: no second refresh, no third attempt.
+    expect(invokeMock).toHaveBeenCalledTimes(3);
+    expect(invokeMock.mock.calls.filter((c) => c[0] === "auth_refresh")).toHaveLength(1);
+  });
+
+  it("propagates the original error when the refresh itself fails", async () => {
+    // The refresh JWT is good for 90 days, but it does eventually
+    // expire (or get revoked). At that point there's nothing left to
+    // do but surface the failure — retrying with the same dead token
+    // would just be a second 401.
+    const { notificationCount } = await import("./client");
+    invokeMock
+      .mockRejectedValueOnce(appviewTokenInvalid("notification count"))
+      .mockRejectedValueOnce("refresh token expired");
+
+    await expect(notificationCount("did:plc:me")).rejects.toThrow(
+      /TokenInvalid/,
+    );
+    expect(invokeMock.mock.calls.map((c) => c[0])).toEqual([
+      "notification_count",
+      "auth_refresh",
+    ]);
+  });
+
+  it("does not refresh on a 403 Forbidden — a new token wouldn't help", async () => {
+    // The AppView returns this when the token is perfectly valid but
+    // its `sub` doesn't match the `did` query parameter. Refreshing
+    // mints another token for the same subject, so a retry is pure
+    // waste.
+    const { fetchTimeline } = await import("./client");
+    invokeMock.mockRejectedValueOnce(
+      'appview: timeline home returned 403 Forbidden: ' +
+        '{"error":"Forbidden","message":"did does not match token subject"}',
+    );
+
+    await expect(fetchTimeline("did:plc:someone-else")).rejects.toThrow(
+      /Forbidden/,
+    );
+    expect(invokeMock).toHaveBeenCalledTimes(1);
+  });
+
+  it("does not refresh when the shell says there is no session at all", async () => {
+    // `require_access_jwt` in lib.rs. Nothing to refresh *from*, so the
+    // message deliberately carries neither `TokenInvalid` nor
+    // `ExpiredSignature`.
+    const { fetchNotifications } = await import("./client");
+    invokeMock.mockRejectedValueOnce(
+      "not logged in: notifications requires a signed-in session",
+    );
+
+    await expect(fetchNotifications("did:plc:me")).rejects.toThrow(
+      /not logged in/,
+    );
+    expect(invokeMock).toHaveBeenCalledTimes(1);
+  });
+
+  it("treats a 503 AuthUnavailable as transient, not as an auth failure", async () => {
+    // The AppView answers 503 `AuthUnavailable` when it cannot reach
+    // the PDS to fetch the verification key — it fails closed rather
+    // than guessing. Our token is fine; the *server* is temporarily
+    // unable to check it. So: no refresh (nothing is wrong with the
+    // token), and `isAuthFailure` must stay false so the background
+    // poll keeps trying instead of shutting itself down over an outage
+    // that will resolve on its own.
+    const { notificationCount, isAuthFailure } = await import("./client");
+    const err =
+      'appview: notification count returned 503 Service Unavailable: ' +
+      '{"error":"AuthUnavailable","message":"could not fetch PDS key"}';
+
+    invokeMock.mockRejectedValueOnce(err);
+    await expect(notificationCount("did:plc:me")).rejects.toThrow(
+      /AuthUnavailable/,
+    );
+    expect(invokeMock).toHaveBeenCalledTimes(1);
+    expect(isAuthFailure(err)).toBe(false);
+  });
+
+  it("does not refresh on a transient server error", async () => {
+    const { notificationCount } = await import("./client");
+    invokeMock.mockRejectedValueOnce(
+      "appview: notification count returned 500 Internal Server Error: db down",
+    );
+
+    await expect(notificationCount("did:plc:me")).rejects.toThrow(/500/);
+    expect(invokeMock).toHaveBeenCalledTimes(1);
+  });
+
+  it("an auth_* command never triggers a refresh (no login loop)", async () => {
+    const { session } = await import("./client");
+    invokeMock.mockRejectedValueOnce("TokenInvalid");
+
+    await expect(session.login("me.test", "pw")).rejects.toBeDefined();
+    expect(invokeMock.mock.calls.map((c) => c[0])).toEqual(["auth_login"]);
+  });
+});
+
+describe("public AppView endpoints", () => {
+  // These stay unauthenticated server-side, so they must keep working
+  // with no session in the store: one invoke, no bearer token to fetch,
+  // no refresh.
+  const PUBLIC = [
+    {
+      name: "search",
+      payload: { posts: [], q: "hi" },
+      call: async () => (await import("./client")).fetchSearch("hi"),
+    },
+    {
+      name: "profile_get",
+      payload: {
+        did: "did:plc:a",
+        handle: "a.test",
+        posts: [],
+        followers: 0,
+        following: 0,
+        post_count: 0,
+      },
+      call: async () => (await import("./client")).fetchProfile("a.test"),
+    },
+    {
+      name: "profile_get_by_did",
+      payload: {
+        did: "did:plc:a",
+        handle: "a.test",
+        posts: [],
+        followers: 0,
+        following: 0,
+        post_count: 0,
+      },
+      call: async () => (await import("./client")).fetchProfileByDid("did:plc:a"),
+    },
+    {
+      name: "post_get",
+      payload: { post: null, thread: { parent: null, root: null } },
+      call: async () =>
+        (await import("./client")).fetchPost("at://did:plc:a/app.twi.post/1"),
+    },
+    {
+      name: "fetch_thread",
+      payload: { post: null, parents: [], root: null, replies: [] },
+      call: async () =>
+        (await import("./client")).fetchThread("at://did:plc:a/app.twi.post/1"),
+    },
+    {
+      name: "fetch_followers",
+      payload: { profiles: [], cursor: null },
+      call: async () => (await import("./client")).fetchFollowers("did:plc:a"),
+    },
+    {
+      name: "fetch_following",
+      payload: { profiles: [], cursor: null },
+      call: async () => (await import("./client")).fetchFollowing("did:plc:a"),
+    },
+  ] as const;
+
+  for (const ep of PUBLIC) {
+    it(`${ep.name} resolves without a session and without refreshing`, async () => {
+      invokeMock.mockResolvedValueOnce(ep.payload);
+
+      await expect(ep.call()).resolves.toBeDefined();
+
+      expect(invokeMock).toHaveBeenCalledTimes(1);
+      expect(invokeMock.mock.calls[0][0]).toBe(ep.name);
+      expect(
+        invokeMock.mock.calls.some((c) => c[0] === "auth_refresh"),
+      ).toBe(false);
+    });
+  }
+
+  it("a public call's own failure surfaces untouched", async () => {
+    const { fetchSearch } = await import("./client");
+    invokeMock.mockRejectedValueOnce(
+      "appview: search returned 400 Bad Request: q is required",
+    );
+    await expect(fetchSearch("")).rejects.toThrow(/q is required/);
+    expect(invokeMock).toHaveBeenCalledTimes(1);
+  });
+});
+
+describe("isAuthFailure / errorMessage", () => {
+  it("recognises every shape the AppView's auth guard can answer with", async () => {
+    const { isAuthFailure } = await import("./client");
+    for (const msg of [
+      'appview: timeline home returned 401 Unauthorized: {"error":"AuthMissing","message":"no bearer"}',
+      'appview: notifications returned 401 Unauthorized: {"error":"TokenInvalid","message":"ExpiredSignature"}',
+      'appview: notification count returned 403 Forbidden: {"error":"Forbidden"}',
+      "not logged in: the home timeline requires a signed-in session",
+    ]) {
+      expect(isAuthFailure(msg)).toBe(true);
+      expect(isAuthFailure(new Error(msg))).toBe(true);
+    }
+  });
+
+  it("does not mistake a server or network failure for an auth failure", async () => {
+    const { isAuthFailure } = await import("./client");
+    expect(
+      isAuthFailure("appview: notifications returned 500: db down"),
+    ).toBe(false);
+    expect(
+      isAuthFailure("appview: failed to send timeline request"),
+    ).toBe(false);
+    expect(isAuthFailure(null)).toBe(false);
+    expect(isAuthFailure(undefined)).toBe(false);
+  });
+
+  it("swaps the raw 401 wire string for copy the user can act on", async () => {
+    const { errorMessage } = await import("./client");
+    const raw =
+      'appview: notifications returned 401 Unauthorized: {"error":"TokenInvalid","message":"ExpiredSignature"}';
+    expect(errorMessage(raw)).toBe(
+      "Sitzung abgelaufen oder abgelehnt — bitte neu anmelden.",
+    );
+    // Anything else is shown verbatim: there's nothing better to say
+    // about a 500 than what the server said.
+    expect(errorMessage("appview: search returned 500: db down")).toContain(
+      "500",
+    );
+  });
+});

crates/tauri-app/src/lib/api/client.ts

@@ -59,14 +59,22 @@ export async function getAppviewUrl(): Promise<string> {
  * webview it falls through to a normal `invoke` call.
  *
  * **Auto-refresh on 401**: the access JWT expires after 1 hour. When
- * the PDS rejects our token with `TokenInvalid` (the rusty
+ * the PDS *or the AppView* rejects our token with `TokenInvalid`
- * `routes::auth` handlers return `{"error":"TokenInvalid",...}`),
+ * (both return `{"error":"TokenInvalid",...}` — the PDS from its
- * we ask the Rust shell for a fresh access JWT via the
+ * `routes::auth` handlers, the AppView from the guard on
- * `auth_refresh` Tauri command. The Rust side reads the stored
+ * `/api/timeline/home`, `/api/notifications`,
- * refresh JWT (valid for 90 days) and rotates both. We retry
+ * `/api/notifications/count` and `/api/notifications/seen`), we ask
- * exactly once on the same `cmd` + `args`. The `auth_*` commands
+ * the Rust shell for a fresh access JWT via the `auth_refresh` Tauri
- * themselves are skipped so a failing login doesn't trigger an
+ * command. The Rust side reads the stored refresh JWT (valid for 90
- * infinite refresh loop.
+ * days) and rotates both. We retry exactly once on the same `cmd` +
+ * `args`. The `auth_*` commands themselves are skipped so a failing
+ * login doesn't trigger an infinite refresh loop.
+ *
+ * The whole chain is string-matching, end to end: the AppView states
+ * the code only in its JSON body, `appview_client.rs`'s
+ * `status_error()` formats that body into the `anyhow` message, and
+ * `lib.rs` stringifies it into the command's `Err(String)`. See the
+ * Rust-side test `token_invalid_code_survives_into_the_error_string`.
  */
 async function safeInvoke<T>(cmd: string, args?: Record<string, unknown>): Promise<T> {
   if (!isTauri()) {
@@ -82,17 +90,74 @@ async function safeInvoke<T>(cmd: string, args?: Record<string, unknown>): Promi
   }
 }
 
+/// Normalise whatever a rejected `invoke` handed us into a string.
+///
+/// This is not defensive padding — it is the difference between the
+/// retry chain working and not. Our Tauri commands are
+/// `Result<T, String>`, and `@tauri-apps/api`'s `invoke` rejects with
+/// the *deserialised* error payload, i.e. a bare JS **string**, not an
+/// `Error`. Anything that only reads `e.message` therefore sees
+/// nothing at all on the exact path that matters. Errors thrown
+/// locally (the browser-preview guard above, and the `Error` instances
+/// the tests use) still arrive as objects, so both shapes are handled.
+function errorText(e: unknown): string {
+  if (typeof e === "string") return e;
+  if (typeof e === "object" && e !== null) {
+    const m = (e as { message?: unknown }).message;
+    if (typeof m === "string") return m;
+  }
+  return String(e ?? "");
+}
+
 /// Sniff out a `TokenInvalid` response from the Rust error string.
-/// Returns true when the error message looks like an expired/
+/// Returns true when the error looks like an expired/invalid JWT —
-/// invalid JWT (the PDS uses a stable `"TokenInvalid"` code in its
+/// both the PDS and the AppView use a stable `"TokenInvalid"` code in
-/// JSON error body, which `@tauri-apps/api/core` surfaces verbatim).
+/// their JSON error body, which travels verbatim through the Rust
+/// error message and out over the Tauri IPC boundary.
 function isTokenInvalid(e: unknown): boolean {
-  if (typeof e !== "object" || e === null) return false;
+  const msg = errorText(e);
-  const msg = (e as { message?: string }).message ?? String(e);
   if (!msg) return false;
   return msg.includes("TokenInvalid") || msg.includes("ExpiredSignature");
 }
 
+/// True when an error means "this call will not succeed until the user
+/// signs in again" — as opposed to a transient network/server hiccup.
+///
+/// Covers everything the AppView's auth guard can answer with
+/// (`AuthMissing` / `TokenInvalid` on 401, `Forbidden` on 403) plus the
+/// Rust shell's own "no session stored" message from
+/// `require_access_jwt`. Callers that poll in the background use this
+/// to *stop* polling: by the time one of these surfaces, `safeInvoke`
+/// has already spent its one refresh attempt, so retrying on a timer
+/// would just be a request loop against a server that keeps saying no.
+export function isAuthFailure(e: unknown): boolean {
+  const msg = errorText(e);
+  if (!msg) return false;
+  return (
+    msg.includes("AuthMissing") ||
+    msg.includes("TokenInvalid") ||
+    msg.includes("ExpiredSignature") ||
+    msg.includes("Forbidden") ||
+    msg.includes("not logged in")
+  );
+}
+
+/// User-facing copy for a failed call, in the app's German UI voice.
+///
+/// An auth failure gets a sentence naming the actual remedy. The raw
+/// string a view would otherwise render —
+/// `appview: timeline home returned 401 Unauthorized:
+/// {"error":"TokenInvalid","message":"ExpiredSignature"}` — is precise
+/// and completely unactionable for the person reading it. Everything
+/// else falls through verbatim: a network error or a 500 is worth
+/// showing as-is, since there is nothing better to say about it.
+export function errorMessage(e: unknown): string {
+  if (isAuthFailure(e)) {
+    return "Sitzung abgelaufen oder abgelehnt — bitte neu anmelden.";
+  }
+  return String(e);
+}
+
 export type Session = {
   did: string;
   handle: string;
@@ -253,8 +318,10 @@ export type SearchResponse = {
 ///
 /// `like_count` and `repost_count` are present when the post was
 /// found; they're `undefined` (or absent) for the "not in index"
-/// sentinel response (where `post` is null). AppView has no auth
+/// sentinel response (where `post` is null). `/api/post/{uri}` is one
-/// yet, so `viewer_liked` / `viewer_reposted` aren't returned.
+/// of the AppView's public endpoints — it takes no token and so has no
+/// viewer to resolve against, hence no `viewer_liked` /
+/// `viewer_reposted`. Use [`fetchThread`] with a `viewerDid` for those.
 export type ThreadResponse = {
   post: Post | null;
   thread: {
@@ -370,6 +437,24 @@ export async function fetchProfile(handle: string): Promise<ProfileResponse> {
   return await safeInvoke<ProfileResponse>("profile_get", { handle });
 }
 
+/// Resolve a profile by DID (`GET /api/profile?did=…`) instead of by
+/// handle.
+///
+/// Use this — not [`fetchProfile`] — whenever the actor came out of a
+/// notification or a follower/following list. The AppView synthesises
+/// a placeholder `handle` for actors it has neither a profile row nor
+/// an indexed post for: a truncated DID with an ellipsis, e.g.
+/// `"did:plc:f5…"`. That string matches nothing on the way back in, and
+/// the server answers with a synthetic empty profile (`did: ""`, zero
+/// posts) rather than an error — so a handle-based navigation from
+/// those lists is a silent dead end. The DID in the DTO is always
+/// real, so navigate by that.
+export async function fetchProfileByDid(
+  did: string,
+): Promise<ProfileResponse> {
+  return await safeInvoke<ProfileResponse>("profile_get_by_did", { did });
+}
+
 export async function fetchSearch(
   q: string,
   limit: number = 30,
@@ -381,6 +466,189 @@ export async function fetchPost(uri: string): Promise<ThreadResponse> {
   return await safeInvoke<ThreadResponse>("post_get", { uri });
 }
 
+/// `GET /api/thread?uri=…` — the *full* thread around a post: the
+/// entire ancestor chain plus the direct replies, in one round trip.
+///
+/// `parents` is ordered root-first (so `parents[parents.length - 1]`
+/// is the immediate parent) and `replies` oldest-first. A `parents[0]`
+/// whose own `parent_uri` is non-null means "the chain continues
+/// above but wasn't loaded" — the walk is depth-limited server-side.
+///
+/// `post` is `null` when the URI isn't in the index; the counters are
+/// then absent too, so a single field check renders "post not found".
+/// `viewer_liked` / `viewer_reposted` are `undefined` when no
+/// `viewerDid` was passed — that means "unknown", not "false".
+export type ThreadFullResponse = {
+  post: Post | null;
+  parents: Post[];
+  root: Post | null;
+  replies: Post[];
+  like_count?: number;
+  repost_count?: number;
+  viewer_liked?: boolean;
+  viewer_reposted?: boolean;
+};
+
+export async function fetchThread(
+  uri: string,
+  viewerDid: string | null = null,
+): Promise<ThreadFullResponse> {
+  return await safeInvoke<ThreadFullResponse>("fetch_thread", {
+    uri,
+    viewerDid,
+  });
+}
+
+/// One row of `GET /api/notifications`, hydrated server-side with the
+/// author's profile and the subject post's text so the list renders
+/// without any follow-up fetch.
+///
+/// `kind` is typed as the four known values plus `string` so an
+/// unknown kind added upstream still type-checks here; the UI's
+/// `notificationText` falls back to a generic line.
+export type NotificationKind = "like" | "repost" | "follow" | "reply";
+
+export type Notification = {
+  id: number;
+  kind: NotificationKind | string;
+  author_did: string;
+  /// Without a leading `@` (the UI renders `@{handle}`). Never null —
+  /// the AppView falls back to a truncated DID.
+  author_handle: string;
+  author_display_name?: string | null;
+  author_avatar_cid?: string | null;
+  /// The post this is about. `null` for `"follow"`. For
+  /// `"like"`/`"repost"` it's the recipient's own post; for `"reply"`
+  /// it's the reply itself.
+  subject_uri: string | null;
+  subject_text?: string | null;
+  created_at: string;
+  /// When the AppView indexed it — the list's sort key and the value
+  /// to echo back as `seenAt`.
+  indexed_at: string;
+  /// `null` while unread.
+  read_at: string | null;
+};
+
+export type NotificationsResponse = {
+  notifications: Notification[];
+  cursor: string | null;
+};
+
+/// German UI copy for a notification row. Kept next to the type (and
+/// exported) so the mapping is unit-testable without mounting a
+/// component. An unrecognised `kind` gets a neutral fallback rather
+/// than an empty line.
+export function notificationText(kind: string): string {
+  switch (kind) {
+    case "like":
+      return "hat deinen Post geliked";
+    case "repost":
+      return "hat repostet";
+    case "follow":
+      return "folgt dir jetzt";
+    case "reply":
+      return "hat geantwortet";
+    default:
+      return "hat interagiert";
+  }
+}
+
+/// Single-glyph icon for a notification row, same switch as
+/// [`notificationText`]. Monospace glyphs rather than SVGs so the
+/// list keeps the terminal look of the rest of the UI.
+export function notificationIcon(kind: string): string {
+  switch (kind) {
+    case "like":
+      return "♥";
+    case "repost":
+      return "⇄";
+    case "follow":
+      return "+";
+    case "reply":
+      return "↩";
+    default:
+      return "•";
+  }
+}
+
+/// One page of notifications, newest first. Same opaque-cursor
+/// contract as [`fetchTimeline`]: pass the previous response's
+/// `cursor` to page down, and `cursor === null` means end of list.
+export async function fetchNotifications(
+  did: string,
+  cursor: string | null = null,
+  limit: number = 30,
+): Promise<NotificationsResponse> {
+  return await safeInvoke<NotificationsResponse>("fetch_notifications", {
+    did,
+    cursor,
+    limit,
+  });
+}
+
+/// Unread-notification count for the NavRail badge. Cheap enough to
+/// poll on the same cadence as the timeline refresh.
+export async function notificationCount(did: string): Promise<number> {
+  const r = await safeInvoke<{ count: number }>("notification_count", { did });
+  return r.count;
+}
+
+/// Mark every notification indexed at or before `seenAt` as read.
+/// Pass the `indexed_at` of the topmost row the user actually sees, so
+/// a notification arriving mid-scroll isn't swallowed. `null` marks
+/// everything currently unread. Idempotent — a repeat call reports
+/// `updated: 0`.
+export async function markNotificationsSeen(
+  did: string,
+  seenAt: string | null = null,
+): Promise<{ ok: boolean; updated: number }> {
+  return await safeInvoke<{ ok: boolean; updated: number }>(
+    "mark_notifications_seen",
+    { did, seenAt },
+  );
+}
+
+/// A minimal profile card from `GET /api/followers` / `/api/following`.
+/// Deliberately not a full `ProfileResponse` — a page of 30 followers
+/// would otherwise be 30 post queries server-side. Click a row and the
+/// UI navigates to the full profile by `handle`.
+export type ActorProfile = {
+  did: string;
+  handle: string;
+  display_name?: string | null;
+  avatar_cid?: string | null;
+};
+
+export type ActorListResponse = {
+  profiles: ActorProfile[];
+  cursor: string | null;
+};
+
+export async function fetchFollowers(
+  did: string,
+  cursor: string | null = null,
+  limit: number = 30,
+): Promise<ActorListResponse> {
+  return await safeInvoke<ActorListResponse>("fetch_followers", {
+    did,
+    cursor,
+    limit,
+  });
+}
+
+export async function fetchFollowing(
+  did: string,
+  cursor: string | null = null,
+  limit: number = 30,
+): Promise<ActorListResponse> {
+  return await safeInvoke<ActorListResponse>("fetch_following", {
+    did,
+    cursor,
+    limit,
+  });
+}
+
 /// `app.bsky.feed.like.create` — Tauri command. Builds the
 /// flat-shape like body on the Rust side, signs a commit, pushes
 /// to the AppView. Returns the new like's `uri` and `cid`.

crates/tauri-app/src/lib/api/notifications.test.ts

@@ -0,0 +1,368 @@
+// Unit tests for the notification / actor-list half of `client.ts`.
+//
+// Same setup as `client.test.ts`: `@tauri-apps/api/core` is mocked so
+// no Tauri shell is needed, and every assertion is about the exact
+// command name + argument bag we hand the Rust IPC layer. That
+// argument bag is the contract — Tauri's `invoke` serialises camelCase
+// JS keys to the snake_case Rust command parameters, so a typo here
+// surfaces at runtime as "command not found" or a null argument, not
+// at compile time.
+//
+// Covered:
+//   * `fetchNotifications` — command name, args, wire→object mapping
+//     (snake_case fields pass through verbatim), cursor pagination;
+//   * `notificationCount` — unwraps `{ count }` to a number;
+//   * `markNotificationsSeen` — sends the `seenAt` watermark;
+//   * `notificationText` / `notificationIcon` — the kind→copy map,
+//     including the fallback for an unknown kind;
+//   * `fetchFollowers` / `fetchFollowing` — distinct commands, same
+//     shape.
+//
+// Run with:
+//   npx vitest run src/lib/api/notifications.test.ts
+
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const invokeMock = vi.fn();
+
+vi.mock("@tauri-apps/api/core", () => ({
+  invoke: (...args: unknown[]) => invokeMock(...args),
+  isTauri: () => true,
+}));
+
+beforeEach(() => {
+  invokeMock.mockReset();
+});
+
+/// A full-fat wire row, exactly as `NotificationItem` serialises it
+/// server-side (snake_case, `read_at` present even when null).
+function wireNotification(over: Record<string, unknown> = {}) {
+  return {
+    id: 1,
+    kind: "like",
+    author_did: "did:plc:alice",
+    author_handle: "alice.test",
+    author_display_name: "Alice",
+    author_avatar_cid: "bafyavatar",
+    subject_uri: "at://did:plc:me/app.twi.post/3k2",
+    subject_text: "hello world",
+    created_at: "2026-09-09T10:00:00Z",
+    indexed_at: "2026-09-09T10:00:01Z",
+    read_at: null,
+    ...over,
+  };
+}
+
+describe("fetchNotifications", () => {
+  it("invokes fetch_notifications and maps the wire rows verbatim", async () => {
+    const { fetchNotifications } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      notifications: [wireNotification()],
+      cursor: "cur1",
+    });
+
+    const r = await fetchNotifications("did:plc:me");
+
+    expect(invokeMock).toHaveBeenCalledTimes(1);
+    expect(invokeMock).toHaveBeenCalledWith("fetch_notifications", {
+      did: "did:plc:me",
+      cursor: null,
+      limit: 30,
+    });
+    expect(r.cursor).toBe("cur1");
+    expect(r.notifications).toHaveLength(1);
+    const n = r.notifications[0];
+    expect(n.id).toBe(1);
+    expect(n.kind).toBe("like");
+    expect(n.author_handle).toBe("alice.test");
+    expect(n.author_display_name).toBe("Alice");
+    expect(n.author_avatar_cid).toBe("bafyavatar");
+    expect(n.subject_uri).toBe("at://did:plc:me/app.twi.post/3k2");
+    expect(n.subject_text).toBe("hello world");
+    expect(n.indexed_at).toBe("2026-09-09T10:00:01Z");
+    // `read_at: null` is the unread marker the badge keys off — it
+    // must survive as null, not become undefined.
+    expect(n.read_at).toBeNull();
+  });
+
+  it("forwards the cursor and limit for a follow-up page", async () => {
+    const { fetchNotifications } = await import("./client");
+    invokeMock.mockResolvedValueOnce({ notifications: [], cursor: null });
+
+    const r = await fetchNotifications("did:plc:me", "cur1", 50);
+
+    expect(invokeMock).toHaveBeenCalledWith("fetch_notifications", {
+      did: "did:plc:me",
+      cursor: "cur1",
+      limit: 50,
+    });
+    // A null cursor is the documented end-of-list sentinel.
+    expect(r.cursor).toBeNull();
+  });
+
+  it("handles a follow row (no subject) without inventing fields", async () => {
+    const { fetchNotifications } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      notifications: [
+        {
+          id: 7,
+          kind: "follow",
+          author_did: "did:plc:bob",
+          author_handle: "bob.test",
+          subject_uri: null,
+          created_at: "2026-09-09T09:00:00Z",
+          indexed_at: "2026-09-09T09:00:01Z",
+          read_at: "2026-09-09T09:30:00Z",
+        },
+      ],
+      cursor: null,
+    });
+
+    const [n] = (await fetchNotifications("did:plc:me")).notifications;
+    expect(n.kind).toBe("follow");
+    expect(n.subject_uri).toBeNull();
+    expect(n.subject_text).toBeUndefined();
+    expect(n.author_display_name).toBeUndefined();
+    expect(n.read_at).toBe("2026-09-09T09:30:00Z");
+  });
+
+  it("propagates a Tauri-side error verbatim", async () => {
+    const { fetchNotifications } = await import("./client");
+    invokeMock.mockRejectedValueOnce(
+      new Error("appview: notifications returned 400: did is required"),
+    );
+    await expect(fetchNotifications("")).rejects.toThrow(
+      /notifications returned 400/,
+    );
+  });
+});
+
+describe("notificationCount", () => {
+  it("unwraps the {count} envelope to a plain number", async () => {
+    const { notificationCount } = await import("./client");
+    invokeMock.mockResolvedValueOnce({ count: 12 });
+
+    const n = await notificationCount("did:plc:me");
+
+    expect(n).toBe(12);
+    expect(invokeMock).toHaveBeenCalledWith("notification_count", {
+      did: "did:plc:me",
+    });
+  });
+
+  it("returns 0 for a fully-read inbox", async () => {
+    const { notificationCount } = await import("./client");
+    invokeMock.mockResolvedValueOnce({ count: 0 });
+    await expect(notificationCount("did:plc:me")).resolves.toBe(0);
+  });
+});
+
+describe("markNotificationsSeen", () => {
+  it("sends the seenAt watermark", async () => {
+    const { markNotificationsSeen } = await import("./client");
+    invokeMock.mockResolvedValueOnce({ ok: true, updated: 4 });
+
+    const r = await markNotificationsSeen(
+      "did:plc:me",
+      "2026-09-09T10:00:01Z",
+    );
+
+    expect(r).toEqual({ ok: true, updated: 4 });
+    expect(invokeMock).toHaveBeenCalledWith("mark_notifications_seen", {
+      did: "did:plc:me",
+      seenAt: "2026-09-09T10:00:01Z",
+    });
+  });
+
+  it("omitting the watermark sends null (mark everything read)", async () => {
+    const { markNotificationsSeen } = await import("./client");
+    invokeMock.mockResolvedValueOnce({ ok: true, updated: 0 });
+
+    await markNotificationsSeen("did:plc:me");
+
+    expect(invokeMock).toHaveBeenCalledWith("mark_notifications_seen", {
+      did: "did:plc:me",
+      seenAt: null,
+    });
+  });
+});
+
+describe("notificationText / notificationIcon", () => {
+  it("maps each kind to its German line", async () => {
+    const { notificationText } = await import("./client");
+    expect(notificationText("like")).toBe("hat deinen Post geliked");
+    expect(notificationText("repost")).toBe("hat repostet");
+    expect(notificationText("follow")).toBe("folgt dir jetzt");
+    expect(notificationText("reply")).toBe("hat geantwortet");
+  });
+
+  it("falls back rather than rendering an empty line for an unknown kind", async () => {
+    const { notificationText } = await import("./client");
+    expect(notificationText("quote")).toBe("hat interagiert");
+    expect(notificationText("")).toBe("hat interagiert");
+  });
+
+  it("gives every known kind its own icon glyph", async () => {
+    const { notificationIcon } = await import("./client");
+    const icons = ["like", "repost", "follow", "reply"].map(notificationIcon);
+    expect(new Set(icons).size).toBe(4);
+    expect(icons.every((i) => i.length > 0)).toBe(true);
+    expect(notificationIcon("quote")).toBe("•");
+  });
+});
+
+describe("fetchFollowers / fetchFollowing", () => {
+  const wireProfile = {
+    did: "did:plc:carol",
+    handle: "carol.test",
+    display_name: "Carol",
+    avatar_cid: "bafycarol",
+  };
+
+  it("fetchFollowers hits the followers command", async () => {
+    const { fetchFollowers } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      profiles: [wireProfile],
+      cursor: null,
+    });
+
+    const r = await fetchFollowers("did:plc:me");
+
+    expect(invokeMock).toHaveBeenCalledWith("fetch_followers", {
+      did: "did:plc:me",
+      cursor: null,
+      limit: 30,
+    });
+    expect(r.profiles[0].handle).toBe("carol.test");
+    expect(r.profiles[0].display_name).toBe("Carol");
+    expect(r.cursor).toBeNull();
+  });
+
+  it("fetchFollowing hits the following command and pages", async () => {
+    const { fetchFollowing } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      profiles: [wireProfile],
+      cursor: "cur2",
+    });
+
+    const r = await fetchFollowing("did:plc:me", "cur1", 10);
+
+    expect(invokeMock).toHaveBeenCalledWith("fetch_following", {
+      did: "did:plc:me",
+      cursor: "cur1",
+      limit: 10,
+    });
+    expect(r.cursor).toBe("cur2");
+  });
+});
+
+describe("fetchProfileByDid", () => {
+  it("invokes profile_get_by_did with the DID", async () => {
+    const { fetchProfileByDid } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      did: "did:plc:f5abcdefghijklmnop",
+      handle: "alice.test",
+      posts: [],
+      followers: 2,
+      following: 3,
+      post_count: 0,
+    });
+
+    const p = await fetchProfileByDid("did:plc:f5abcdefghijklmnop");
+
+    expect(invokeMock).toHaveBeenCalledWith("profile_get_by_did", {
+      did: "did:plc:f5abcdefghijklmnop",
+    });
+    expect(p.did).toBe("did:plc:f5abcdefghijklmnop");
+    expect(p.followers).toBe(2);
+  });
+
+  it("resolves an actor whose only known handle is a truncated-DID placeholder", async () => {
+    // The dead end this endpoint exists to avoid: the AppView hands
+    // us `handle: "did:plc:f5a…"` (from `short_did_bare`) for an actor
+    // it has no profile row or indexed post for. Feeding that back
+    // into the *handle* lookup matches nothing and the server answers
+    // 200 with a synthetic empty profile — `did: ""`, zero counts —
+    // so the UI shows a blank page instead of an error. The DID
+    // lookup resolves the real row.
+    const { fetchProfile, fetchProfileByDid } = await import("./client");
+
+    const placeholderHandle = "did:plc:f5a…";
+    const realDid = "did:plc:f5abcdefghijklmnop";
+
+    // 1. What the handle path actually gets back today.
+    invokeMock.mockResolvedValueOnce({
+      did: "",
+      handle: placeholderHandle,
+      posts: [],
+      followers: 0,
+      following: 0,
+      post_count: 0,
+    });
+    const viaHandle = await fetchProfile(placeholderHandle);
+    expect(viaHandle.did).toBe("");
+    expect(viaHandle.post_count).toBe(0);
+
+    // 2. What the DID path gets back — the real profile.
+    invokeMock.mockResolvedValueOnce({
+      did: realDid,
+      handle: "alice.test",
+      posts: [],
+      followers: 5,
+      following: 1,
+      post_count: 12,
+    });
+    const viaDid = await fetchProfileByDid(realDid);
+    expect(viaDid.did).toBe(realDid);
+    expect(viaDid.handle).toBe("alice.test");
+    expect(viaDid.post_count).toBe(12);
+
+    // The two calls must be distinct commands — a shared one would
+    // reintroduce the ambiguity.
+    expect(invokeMock.mock.calls.map((c) => c[0])).toEqual([
+      "profile_get",
+      "profile_get_by_did",
+    ]);
+  });
+});
+
+describe("fetchThread", () => {
+  it("invokes fetch_thread with the viewer DID", async () => {
+    const { fetchThread } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      post: null,
+      parents: [],
+      root: null,
+      replies: [],
+    });
+
+    const r = await fetchThread("at://did:plc:me/app.twi.post/3k2", "did:plc:me");
+
+    expect(invokeMock).toHaveBeenCalledWith("fetch_thread", {
+      uri: "at://did:plc:me/app.twi.post/3k2",
+      viewerDid: "did:plc:me",
+    });
+    // `post: null` is the "not in our index" sentinel — one field
+    // check is enough to render "post not found".
+    expect(r.post).toBeNull();
+    expect(r.parents).toEqual([]);
+    expect(r.replies).toEqual([]);
+  });
+
+  it("defaults the viewer DID to null", async () => {
+    const { fetchThread } = await import("./client");
+    invokeMock.mockResolvedValueOnce({
+      post: null,
+      parents: [],
+      root: null,
+      replies: [],
+    });
+
+    await fetchThread("at://did:plc:me/app.twi.post/3k2");
+
+    expect(invokeMock).toHaveBeenCalledWith("fetch_thread", {
+      uri: "at://did:plc:me/app.twi.post/3k2",
+      viewerDid: null,
+    });
+  });
+});

crates/tauri-app/src/lib/components/NavRail.svelte

@@ -4,18 +4,35 @@
   // `$bindable`, use a callback prop to bubble state changes up to
   // the parent.
 
-  type View = "home" | "compose" | "profile" | "user" | "search" | "settings";
+  type View =
+    | "home"
+    | "notifications"
+    | "compose"
+    | "profile"
+    | "user"
+    | "search"
+    | "settings";
 
   let {
     view = "home",
     on_select,
+    unread = 0,
   }: {
     view?: View;
     on_select?: (v: View) => void;
+    /// Unread-notification count from `/api/notifications/count`.
+    /// The parent polls it and hands it down; `0` (or anything
+    /// below) hides the badge entirely rather than rendering a "0".
+    unread?: number;
   } = $props();
 
+  /// Badge label. Anything past 99 collapses to "99+" so a long
+  /// unread backlog can't widen the 88px rail.
+  const badge = $derived(unread > 99 ? "99+" : String(unread));
+
   const items: Array<{ id: View; label: string; key: string; icon: string }> = [
     { id: "home", label: "home", key: "g h", icon: "home" },
+    { id: "notifications", label: "notifs", key: "g n", icon: "bell" },
     { id: "compose", label: "compose", key: "c", icon: "compose" },
     { id: "profile", label: "profile", key: "p", icon: "profile" },
     { id: "search", label: "search", key: "/", icon: "search" },
@@ -37,6 +54,10 @@
           <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.6">
             <path d="M3 11l9-8 9 8v9a2 2 0 0 1-2 2h-3v-7H8v7H5a2 2 0 0 1-2-2z"/>
           </svg>
+        {:else if item.icon === "bell"}
+          <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round">
+            <path d="M18 15v-4a6 6 0 1 0-12 0v4l-2 3h16z"/><path d="M10 21h4"/>
+          </svg>
         {:else if item.icon === "compose"}
           <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.6" stroke-linecap="round">
             <text x="3" y="17" font-family="ui-monospace,monospace" font-size="14" font-weight="700" fill="currentColor" stroke="none">&gt;_</text>
@@ -55,6 +76,16 @@
             <circle cx="11" cy="11" r="7"/><path d="m20 20-3-3"/>
           </svg>
         {/if}
+        {#if item.id === "notifications" && unread > 0}
+          <!-- Live region so a screen reader announces a badge that
+               appears while the rail is already on screen. -->
+          <span
+            class="badge"
+            data-testid="notif-badge"
+            aria-live="polite"
+            aria-label={`${unread} ungelesene Benachrichtigungen`}
+          >{badge}</span>
+        {/if}
       </span>
       <span class="label">{item.label}</span>
     </button>
@@ -107,6 +138,26 @@
     height: 24px;
     display: grid;
     place-items: center;
+    /* Anchor for the unread badge, which overhangs the glyph's
+       top-right corner the way a tray badge does. */
+    position: relative;
+  }
+  .badge {
+    position: absolute;
+    top: -6px;
+    right: -10px;
+    min-width: 16px;
+    padding: 0 4px;
+    border-radius: var(--r-pill);
+    background: var(--orange);
+    color: var(--bg);
+    font-family: var(--font-mono);
+    font-size: 10px;
+    line-height: 16px;
+    font-weight: 700;
+    text-align: center;
+    font-variant-numeric: tabular-nums;
+    pointer-events: none;
   }
   .icon :global(svg) {
     width: 22px;

crates/tauri-app/src/lib/components/NavRail.test.ts

@@ -5,6 +5,10 @@
 //
 // Pattern: `let view = $state("home")` in the harness, then the
 // `on_select` callback updates it (same shape as App.svelte).
+//
+// The rail order is: home, notifications, compose, profile, search,
+// settings. The indices below follow that order — if you reorder the
+// `items` array in NavRail.svelte, update them here too.
 
 import { afterEach, beforeEach, describe, expect, it } from "vitest";
 import { mount, unmount, tick } from "svelte";
@@ -23,16 +27,16 @@ afterEach(() => {
   target.remove();
 });
 
-async function mountHarness() {
+async function mountHarness(props: { unread?: number } = {}) {
-  app = mount(NavRailHarness, { target });
+  app = mount(NavRailHarness, { target, props });
   await tick();
 }
 
 describe("NavRail (callback-prop pattern)", () => {
-  it("renders 5 buttons with home active", async () => {
+  it("renders 6 buttons with home active", async () => {
     await mountHarness();
     const btns = target.querySelectorAll("button.rail__btn");
-    expect(btns.length).toBe(5);
+    expect(btns.length).toBe(6);
     expect(btns[0].classList.contains("active")).toBe(true);
     expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("home");
   });
@@ -41,25 +45,68 @@ describe("NavRail (callback-prop pattern)", () => {
     await mountHarness();
     const btns = target.querySelectorAll("button.rail__btn");
 
-    btns[3].dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    btns[4].dispatchEvent(new MouseEvent("click", { bubbles: true }));
     await tick();
     expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("search");
-    expect(btns[3].classList.contains("active")).toBe(true);
+    expect(btns[4].classList.contains("active")).toBe(true);
     expect(btns[0].classList.contains("active")).toBe(false);
 
-    btns[1].dispatchEvent(new MouseEvent("click", { bubbles: true }));
-    await tick();
-    expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("compose");
-    expect(btns[1].classList.contains("active")).toBe(true);
-
     btns[2].dispatchEvent(new MouseEvent("click", { bubbles: true }));
     await tick();
-    expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("profile");
+    expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("compose");
     expect(btns[2].classList.contains("active")).toBe(true);
 
-    btns[4].dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    btns[3].dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    await tick();
+    expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("profile");
+    expect(btns[3].classList.contains("active")).toBe(true);
+
+    btns[5].dispatchEvent(new MouseEvent("click", { bubbles: true }));
     await tick();
     expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe("settings");
-    expect(btns[4].classList.contains("active")).toBe(true);
+    expect(btns[5].classList.contains("active")).toBe(true);
+  });
+
+  it("routes to the notifications view", async () => {
+    await mountHarness();
+    const btns = target.querySelectorAll("button.rail__btn");
+
+    btns[1].dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    await tick();
+    expect(target.querySelector('[data-testid="view-value"]')?.textContent).toBe(
+      "notifications",
+    );
+    expect(btns[1].classList.contains("active")).toBe(true);
+  });
+});
+
+describe("NavRail unread badge", () => {
+  it("renders no badge at zero unread", async () => {
+    await mountHarness({ unread: 0 });
+    expect(target.querySelector('[data-testid="notif-badge"]')).toBeNull();
+  });
+
+  it("renders the count on the notifications button", async () => {
+    await mountHarness({ unread: 3 });
+    const badge = target.querySelector('[data-testid="notif-badge"]');
+    expect(badge).not.toBeNull();
+    expect(badge?.textContent?.trim()).toBe("3");
+    // The badge must sit on the notifications entry, not on some
+    // other rail button.
+    const btns = target.querySelectorAll("button.rail__btn");
+    expect(btns[1].contains(badge!)).toBe(true);
+  });
+
+  it("caps a large backlog at 99+ so the 88px rail can't widen", async () => {
+    await mountHarness({ unread: 1234 });
+    const badge = target.querySelector('[data-testid="notif-badge"]');
+    expect(badge?.textContent?.trim()).toBe("99+");
+  });
+
+  it("keeps 99 unabbreviated (the cap is exclusive)", async () => {
+    await mountHarness({ unread: 99 });
+    expect(
+      target.querySelector('[data-testid="notif-badge"]')?.textContent?.trim(),
+    ).toBe("99");
   });
 });

crates/tauri-app/src/lib/components/NavRailHarness.svelte

@@ -5,12 +5,26 @@
 
   import NavRail from "./NavRail.svelte";
 
-  type View = "home" | "compose" | "profile" | "user" | "search" | "settings";
+  type View =
+    | "home"
+    | "notifications"
+    | "compose"
+    | "profile"
+    | "user"
+    | "search"
+    | "settings";
+
+  // `unread` is a prop so the badge test can drive it without going
+  // through the polling path in App.svelte. Defaults to 0 (no badge),
+  // which is what every non-badge test expects.
+  let { unread = 0 }: { unread?: number } = $props();
+
   let view: View = $state("home");
 </script>
 
 <NavRail
   {view}
+  {unread}
   on_select={(v) => {
     view = v;
   }}

crates/tauri-app/src/lib/components/NotificationsView.svelte

@@ -0,0 +1,367 @@
+<script lang="ts">
+  import Avatar from "./Avatar.svelte";
+  import Skeleton from "./Skeleton.svelte";
+  import {
+    errorMessage,
+    fetchNotifications,
+    markNotificationsSeen,
+    notificationIcon,
+    notificationText,
+    type Notification,
+  } from "../api/client";
+
+  type Props = {
+    /// Recipient DID — whose notifications to list.
+    did: string;
+    /// Opens the thread for a notification's `subject_uri`. Wired to
+    /// App.svelte's existing `openThread` helper, so a notification
+    /// and a PostCard's thread button land in the same modal.
+    on_thread_click?: (uri: string) => void;
+    /// Navigates to the author's profile. Takes the DID *and* the
+    /// handle, and the DID is what the navigation resolves by: the
+    /// AppView hands us a placeholder handle (a truncated DID, see
+    /// `short_did_bare`) for any author it has neither a profile row
+    /// nor an indexed post for, and that placeholder resolves to a
+    /// synthetic empty profile on the way back in. `author_did` is
+    /// always real, so it's the one field worth navigating on. The
+    /// handle still travels along for the header label while the
+    /// profile loads.
+    on_actor_click?: (did: string, handle: string) => void;
+    /// Fired once the first page is marked read, so the parent can
+    /// zero the NavRail badge without waiting for the next poll.
+    on_seen?: () => void;
+  };
+
+  let { did, on_thread_click, on_actor_click, on_seen }: Props = $props();
+
+  let items: Notification[] = $state([]);
+  let cursor: string | null = $state(null);
+  let loading: boolean = $state(false);
+  let error: string | null = $state(null);
+  /// Guards `load()` against a re-entrant `$effect` run: the effect
+  /// tracks `did`, but `load` writes `$state` the effect would
+  /// otherwise see as a self-write (the same depth-guard problem
+  /// ProfileView documents around `untrack`).
+  let loadedDid: string | null = null;
+
+  async function load() {
+    loading = true;
+    error = null;
+    try {
+      const r = await fetchNotifications(did, null, 30);
+      items = r.notifications;
+      cursor = r.cursor;
+      // Watermark the read marker at the newest row we actually
+      // rendered — never `null` — so a notification that lands while
+      // the user is scrolling isn't silently marked as seen.
+      const top = r.notifications[0]?.indexed_at ?? null;
+      if (top) {
+        try {
+          await markNotificationsSeen(did, top);
+          // Reflect it locally too: the rows are already on screen,
+          // and re-fetching just to flip `read_at` would be a wasted
+          // round trip.
+          items = items.map((n) =>
+            n.read_at ? n : { ...n, read_at: top },
+          );
+          on_seen?.();
+        } catch (e) {
+          // A failed ack is not a failed load — the list is usable,
+          // the badge just stays until the next attempt.
+          console.warn("mark_notifications_seen failed", e);
+        }
+      }
+    } catch (e) {
+      error = errorMessage(e);
+    } finally {
+      loading = false;
+    }
+  }
+
+  async function loadMore() {
+    if (!cursor || loading) return;
+    loading = true;
+    try {
+      const r = await fetchNotifications(did, cursor, 30);
+      // De-dupe on `id`: the keyset cursor is stable, but a row
+      // indexed between two page fetches can otherwise shift a row
+      // across the page boundary.
+      const seen = new Set(items.map((n) => n.id));
+      items = [...items, ...r.notifications.filter((n) => !seen.has(n.id))];
+      cursor = r.cursor;
+    } catch (e) {
+      error = errorMessage(e);
+    } finally {
+      loading = false;
+    }
+  }
+
+  $effect(() => {
+    if (!did || loadedDid === did) return;
+    loadedDid = did;
+    void load();
+  });
+
+  /// Display label for the author — the profile's display name when
+  /// the AppView has one cached, else the handle (which the server
+  /// guarantees is non-empty, falling back to a truncated DID).
+  function authorName(n: Notification): string {
+    return n.author_display_name || n.author_handle;
+  }
+
+  /// Same relative-time rendering as PostCard's `timeAgo`, on
+  /// `indexed_at` (the list's sort key) rather than `created_at`.
+  function timeAgo(iso: string): string {
+    const timestamp = new Date(iso).getTime();
+    if (!Number.isFinite(timestamp)) return iso;
+    const seconds = Math.max(0, Math.floor((Date.now() - timestamp) / 1000));
+    if (seconds < 60) return `${seconds}s`;
+    if (seconds < 3600) return `${Math.floor(seconds / 60)}m`;
+    if (seconds < 86400) return `${Math.floor(seconds / 3600)}h`;
+    return `${Math.floor(seconds / 86400)}d`;
+  }
+
+  function openSubject(n: Notification) {
+    if (!n.subject_uri) return;
+    on_thread_click?.(n.subject_uri);
+  }
+</script>
+
+<section class="notifs">
+  {#if error}
+    <div class="notifs__err">err: {error}</div>
+  {/if}
+
+  {#if loading && items.length === 0}
+    <Skeleton rows={3} />
+  {:else if items.length === 0}
+    <div class="notifs__empty">// keine Benachrichtigungen.</div>
+  {:else}
+    <ul class="notifs__list">
+      {#each items as n (n.id)}
+        <li class="notifs__item" class:notifs__item--unread={!n.read_at}>
+          <!--
+            The whole row is the click target when there's a subject
+            to open; for a "follow" (no subject) the row is inert and
+            only the handle button navigates. `type="button"` +
+            `disabled` keeps the keyboard order honest instead of
+            faking it with a div.
+          -->
+          <button
+            class="notifs__row"
+            type="button"
+            disabled={!n.subject_uri}
+            aria-label={`${authorName(n)} ${notificationText(n.kind)}`}
+            onclick={() => openSubject(n)}
+          >
+            <span class="notifs__icon" data-kind={n.kind} aria-hidden="true">
+              {notificationIcon(n.kind)}
+            </span>
+            <span class="notifs__avatar">
+              <Avatar
+                did={n.author_did}
+                cid={n.author_avatar_cid ?? null}
+                name={authorName(n)}
+                size={32}
+              />
+            </span>
+            <span class="notifs__body">
+              <span class="notifs__line">
+                <span class="notifs__name">{authorName(n)}</span>
+                <span class="notifs__text">{notificationText(n.kind)}</span>
+                <span class="notifs__age">{timeAgo(n.indexed_at)}</span>
+              </span>
+              {#if n.subject_text}
+                <span class="notifs__subject">{n.subject_text}</span>
+              {/if}
+            </span>
+          </button>
+          <button
+            class="notifs__handle"
+            type="button"
+            title={n.author_did}
+            onclick={() => on_actor_click?.(n.author_did, n.author_handle)}
+          >@{n.author_handle}</button>
+        </li>
+      {/each}
+    </ul>
+    {#if cursor}
+      <div class="notifs__loadmore">
+        <button
+          class="notifs__btn"
+          type="button"
+          disabled={loading}
+          onclick={() => void loadMore()}
+        >
+          {loading ? "loading…" : "load more"}
+        </button>
+      </div>
+    {/if}
+  {/if}
+</section>
+
+<style>
+  .notifs {
+    padding: 0 0 var(--s-6);
+  }
+  .notifs__err {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    padding: var(--s-2) var(--s-3);
+    margin: 0 var(--s-5) var(--s-3);
+    border-left: 3px solid var(--red);
+    background: var(--orange-3);
+    color: var(--red);
+    border-radius: 0 var(--r-sm) var(--r-sm) 0;
+  }
+  .notifs__empty {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    color: var(--text-dim);
+    padding: var(--s-4) var(--s-5);
+    font-style: italic;
+  }
+  .notifs__list {
+    list-style: none;
+    margin: 0;
+    padding: 0;
+  }
+  /* One row per notification: the clickable body plus the handle
+     button, which is a separate target so "open the thread" and "go
+     to the author" don't fight over the same click. */
+  .notifs__item {
+    display: flex;
+    align-items: center;
+    gap: var(--s-2);
+    padding: 0 var(--s-4) 0 0;
+    border-bottom: 1px solid var(--line);
+  }
+  /* Unread rows get the orange left rail + tint the rest of the app
+     uses for "needs attention" (same tokens as the settings hover
+     state), so the read/unread split is visible without a legend. */
+  .notifs__item--unread {
+    background: var(--orange-8);
+    box-shadow: inset 3px 0 0 var(--orange);
+  }
+  .notifs__row {
+    flex: 1 1 auto;
+    min-width: 0;
+    display: flex;
+    align-items: center;
+    gap: var(--s-3);
+    padding: var(--s-3) var(--s-4);
+    background: transparent;
+    border: 0;
+    text-align: left;
+    cursor: pointer;
+    color: var(--text);
+    font-family: var(--font-mono);
+    transition: background-color var(--dur) var(--ease);
+  }
+  .notifs__row:hover:not(:disabled) {
+    background: var(--orange-3);
+  }
+  .notifs__row:disabled {
+    cursor: default;
+  }
+  .notifs__icon {
+    flex: 0 0 auto;
+    width: 1.25rem;
+    text-align: center;
+    font-size: var(--fs-100);
+    color: var(--text-dim);
+  }
+  /* Per-kind accent: likes red, reposts green, follows/replies cyan
+     — all straight from the token palette, no new hex values. */
+  .notifs__icon[data-kind="like"] { color: var(--red); }
+  .notifs__icon[data-kind="repost"] { color: var(--green); }
+  .notifs__icon[data-kind="follow"] { color: var(--cyan); }
+  .notifs__icon[data-kind="reply"] { color: var(--orange); }
+  .notifs__avatar {
+    flex: 0 0 auto;
+    line-height: 0;
+  }
+  .notifs__body {
+    display: flex;
+    flex-direction: column;
+    gap: 2px;
+    min-width: 0;
+  }
+  .notifs__line {
+    display: flex;
+    align-items: baseline;
+    gap: var(--s-2);
+    min-width: 0;
+  }
+  .notifs__name {
+    color: var(--text);
+    font-weight: 700;
+    font-size: var(--fs-50);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+  .notifs__text {
+    color: var(--text-dim);
+    font-size: var(--fs-50);
+    white-space: nowrap;
+  }
+  .notifs__age {
+    color: var(--text-dim);
+    font-size: var(--fs-50);
+    font-variant-numeric: tabular-nums;
+    margin-left: auto;
+    flex: 0 0 auto;
+  }
+  /* Subject preview — one line, clipped. The full text is a click
+     away in the thread, so wrapping here would only push rows apart. */
+  .notifs__subject {
+    color: var(--text-dim);
+    font-size: var(--fs-50);
+    font-family: var(--font-sans);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+  .notifs__handle {
+    flex: 0 0 auto;
+    background: transparent;
+    border: 0;
+    color: var(--text-dim);
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    cursor: pointer;
+    padding: var(--s-1) var(--s-2);
+    border-radius: var(--r-sm);
+    transition: color var(--dur) var(--ease);
+  }
+  .notifs__handle:hover {
+    color: var(--orange);
+  }
+  .notifs__loadmore {
+    display: flex;
+    justify-content: center;
+    padding: var(--s-4) var(--s-5);
+  }
+  .notifs__btn {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    padding: 0.4rem 0.8rem;
+    border-radius: var(--r-sm);
+    border: 1px solid var(--line-2);
+    background: transparent;
+    color: var(--text-dim);
+    cursor: pointer;
+    transition:
+      color var(--dur) var(--ease),
+      border-color var(--dur) var(--ease);
+  }
+  .notifs__btn:hover:not(:disabled) {
+    color: var(--orange);
+    border-color: var(--orange);
+  }
+  .notifs__btn:disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+  }
+</style>

crates/tauri-app/src/lib/components/NotificationsView.test.ts

@@ -0,0 +1,261 @@
+// Regression guard for the actor-navigation path out of the
+// notifications list.
+//
+// The AppView guarantees `author_handle` is non-empty, but it does NOT
+// guarantee it's a real handle: for an author it has neither a
+// `profiles` row nor an indexed post for, it synthesises a placeholder
+// from the DID (`short_did_bare` in the AppView's `routes.rs`) — e.g.
+// `"did:plc:f5…"`, a truncated DID with an ellipsis. Navigating with
+// that string resolves to nothing, and `/api/profile/<handle>` answers
+// with a *synthetic empty profile* rather than an error, so the click
+// silently dead-ends on a blank page.
+//
+// The fix is to hand the navigation callback the real `author_did`
+// alongside the handle. These tests pin that: the callback must
+// receive the DID from the DTO, for both a real-handle author and a
+// placeholder-handle one.
+
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { mount, unmount, tick } from "svelte";
+
+const fetchNotificationsMock = vi.fn();
+const markNotificationsSeenMock = vi.fn();
+
+vi.mock("../api/client", async () => {
+  // Keep the real `notificationText` / `notificationIcon` — the row
+  // copy is part of what we're rendering — and stub only the two
+  // functions that would otherwise need a Tauri runtime.
+  const actual =
+    await vi.importActual<typeof import("../api/client")>("../api/client");
+  return {
+    ...actual,
+    fetchNotifications: (...args: unknown[]) => fetchNotificationsMock(...args),
+    markNotificationsSeen: (...args: unknown[]) =>
+      markNotificationsSeenMock(...args),
+    // Avatar resolves blobs through this; every fixture below has a
+    // null avatar CID so it never fires, but stub it so a stray call
+    // can't reach for the Tauri shell.
+    fetchBlob: () => Promise.reject(new Error("no blob in test")),
+  };
+});
+
+import NotificationsView from "./NotificationsView.svelte";
+
+let target: HTMLDivElement;
+let app: ReturnType<typeof mount> | null = null;
+
+beforeEach(() => {
+  target = document.createElement("div");
+  document.body.appendChild(target);
+  fetchNotificationsMock.mockReset();
+  markNotificationsSeenMock.mockReset();
+  markNotificationsSeenMock.mockResolvedValue({ ok: true, updated: 1 });
+});
+
+afterEach(() => {
+  if (app) unmount(app);
+  app = null;
+  target.remove();
+});
+
+/// Let the component's load effect and its awaited promises settle.
+/// The mocked fetch resolves immediately, so a handful of microtask
+/// turns plus a Svelte flush is enough.
+async function flush(turns = 6) {
+  for (let i = 0; i < turns; i++) {
+    await Promise.resolve();
+    await tick();
+  }
+}
+
+function row(over: Record<string, unknown> = {}) {
+  return {
+    id: 1,
+    kind: "like",
+    author_did: "did:plc:realauthor",
+    author_handle: "alice.test",
+    author_avatar_cid: null,
+    subject_uri: "at://did:plc:me/app.twi.post/3k2",
+    subject_text: "hello",
+    created_at: "2026-09-09T10:00:00Z",
+    indexed_at: "2026-09-09T10:00:01Z",
+    read_at: null,
+    ...over,
+  };
+}
+
+describe("NotificationsView actor navigation", () => {
+  it("hands the callback the author DID, not just the handle", async () => {
+    fetchNotificationsMock.mockResolvedValue({
+      notifications: [row()],
+      cursor: null,
+    });
+    const onActorClick = vi.fn();
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me", on_actor_click: onActorClick },
+    });
+    await flush();
+
+    const handleBtn = target.querySelector("button.notifs__handle");
+    expect(handleBtn).not.toBeNull();
+    handleBtn!.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    await tick();
+
+    expect(onActorClick).toHaveBeenCalledTimes(1);
+    expect(onActorClick).toHaveBeenCalledWith(
+      "did:plc:realauthor",
+      "alice.test",
+    );
+  });
+
+  it("resolves an author whose handle is only a truncated-DID placeholder", async () => {
+    // Exactly what the AppView returns for an author it has never
+    // seen post and has no profile row for: `handle` is
+    // `short_did_bare(author_did)`, which matches nothing on the way
+    // back in. The DID beside it is real.
+    fetchNotificationsMock.mockResolvedValue({
+      notifications: [
+        row({
+          id: 2,
+          kind: "follow",
+          author_did: "did:plc:f5abcdefghijklmnop",
+          author_handle: "did:plc:f5a…",
+          subject_uri: null,
+          subject_text: undefined,
+        }),
+      ],
+      cursor: null,
+    });
+    const onActorClick = vi.fn();
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me", on_actor_click: onActorClick },
+    });
+    await flush();
+
+    target
+      .querySelector("button.notifs__handle")!
+      .dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    await tick();
+
+    const [didArg, handleArg] = onActorClick.mock.calls[0];
+    // The DID must be the full, real one — never the truncated
+    // display string.
+    expect(didArg).toBe("did:plc:f5abcdefghijklmnop");
+    expect(didArg).not.toContain("…");
+    // The placeholder still travels as the label, which is fine — it
+    // is not what the lookup keys off.
+    expect(handleArg).toBe("did:plc:f5a…");
+  });
+
+  it("renders the kind copy and marks the first page seen at the top row", async () => {
+    fetchNotificationsMock.mockResolvedValue({
+      notifications: [row({ kind: "follow", subject_uri: null })],
+      cursor: null,
+    });
+    const onSeen = vi.fn();
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me", on_seen: onSeen },
+    });
+    await flush();
+
+    expect(target.textContent).toContain("folgt dir jetzt");
+    // The read watermark is the newest rendered row's `indexed_at` —
+    // never null, so a notification landing mid-scroll survives.
+    expect(markNotificationsSeenMock).toHaveBeenCalledWith(
+      "did:plc:me",
+      "2026-09-09T10:00:01Z",
+    );
+    expect(onSeen).toHaveBeenCalledTimes(1);
+  });
+
+  it("a follow row has no thread target, so its row button is inert", async () => {
+    fetchNotificationsMock.mockResolvedValue({
+      notifications: [row({ kind: "follow", subject_uri: null })],
+      cursor: null,
+    });
+    const onThreadClick = vi.fn();
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me", on_thread_click: onThreadClick },
+    });
+    await flush();
+
+    const rowBtn = target.querySelector<HTMLButtonElement>("button.notifs__row");
+    expect(rowBtn?.disabled).toBe(true);
+    rowBtn!.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    await tick();
+    expect(onThreadClick).not.toHaveBeenCalled();
+  });
+
+  it("shows actionable copy when the AppView rejects the session", async () => {
+    // Since `/api/notifications` grew an auth guard, this is what a
+    // rejected token looks like by the time it reaches the view: the
+    // AppView's JSON body, wrapped by `appview_client.rs`'s
+    // `status_error()` and stringified across the Tauri IPC boundary.
+    // `safeInvoke` has already spent its one refresh attempt getting
+    // here, so the only thing left to tell the user is "log in again" —
+    // rendering the raw wire string would be accurate and useless.
+    fetchNotificationsMock.mockRejectedValue(
+      'appview: notifications returned 401 Unauthorized: ' +
+        '{"error":"TokenInvalid","message":"ExpiredSignature"}',
+    );
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me" },
+    });
+    await flush();
+
+    expect(target.textContent).toContain("bitte neu anmelden");
+    expect(target.textContent).not.toContain("TokenInvalid");
+    expect(target.textContent).not.toContain("401");
+    // A failed load must not leave the spinner up or ack a page it
+    // never rendered.
+    expect(markNotificationsSeenMock).not.toHaveBeenCalled();
+  });
+
+  it("still shows a server error verbatim — there's nothing better to say", async () => {
+    fetchNotificationsMock.mockRejectedValue(
+      "appview: notifications returned 500 Internal Server Error: db down",
+    );
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me" },
+    });
+    await flush();
+
+    expect(target.textContent).toContain("500");
+    expect(target.textContent).toContain("db down");
+  });
+
+  it("opens the thread for a row that has a subject", async () => {
+    fetchNotificationsMock.mockResolvedValue({
+      notifications: [row()],
+      cursor: null,
+    });
+    const onThreadClick = vi.fn();
+
+    app = mount(NotificationsView, {
+      target,
+      props: { did: "did:plc:me", on_thread_click: onThreadClick },
+    });
+    await flush();
+
+    target
+      .querySelector("button.notifs__row")!
+      .dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    await tick();
+
+    expect(onThreadClick).toHaveBeenCalledWith(
+      "at://did:plc:me/app.twi.post/3k2",
+    );
+  });
+});

crates/tauri-app/src/lib/components/ProfileView.svelte

@@ -9,22 +9,49 @@
     getAppviewUrl,
     followUser,
     unfollowUser,
+    fetchFollowers,
+    fetchFollowing,
+    fetchProfileByDid,
     showInfo,
     showError,
+    type ActorProfile,
   } from "../api/client";
   import { localStorageKey } from "../utils/localstorage";
-  import { onDestroy, onMount, untrack } from "svelte";
+  import { onDestroy, untrack } from "svelte";
 
   type Props = {
     handle: string;
+    /// DID of the profile to show, when the caller already knows it.
+    /// Takes precedence over `handle`: the AppView synthesises a
+    /// placeholder handle (a truncated DID — `short_did_bare`) for
+    /// actors it has neither a `profiles` row nor an indexed post for,
+    /// and feeding that back into the handle lookup resolves to a
+    /// synthetic empty profile. Navigation out of a notification or a
+    /// follower list therefore passes the DID; `handle` is still
+    /// supplied so the header has a label while the fetch is in
+    /// flight. `null`/absent keeps the handle lookup (PostCard header,
+    /// search, the current user's own profile).
+    did?: string | null;
     on_thread_click?: (uri: string) => void;
     /// DID of the authenticated user. When this matches the
     /// profile's DID, the "edit profile" button is shown; the
     /// /user-profile/<handle> route is then the user's own
     /// profile (and the avatar / bio are editable).
     current_user_did?: string | null;
+    /// Navigate to another profile. Receives `(did, handle)` and the
+    /// caller resolves by DID — see the `did` prop above for why the
+    /// handle alone is not a reliable key. Used by the follower /
+    /// following list rows and by the PostCards in the feed (which
+    /// carry a real `post.did`).
+    on_actor_click?: (did: string, handle: string) => void;
   };
-  let { handle, on_thread_click, current_user_did }: Props = $props();
+  let {
+    handle,
+    did = null,
+    on_thread_click,
+    current_user_did,
+    on_actor_click,
+  }: Props = $props();
 
   type State =
     | { kind: "loading" }
@@ -91,6 +118,15 @@
   async function load() {
     viewModel = { kind: "loading" };
     try {
+      // DID lookup wins when the caller supplied one — see the `did`
+      // prop. `/api/profile?did=…` is an exact match on the `posts` /
+      // `profiles` DID column, so it works for an actor whose only
+      // known "handle" is the server's truncated-DID placeholder.
+      if (did) {
+        const data = (await fetchProfileByDid(did)) as AppViewProfile;
+        viewModel = { kind: "ready", data };
+        return;
+      }
       // Absolute URL because the Tauri webview's origin is the Vite
       // dev server (port 1430), not the AppView (port 2584) — a
       // relative `/api/profile/…` would resolve against Vite, hit a
@@ -145,8 +181,25 @@
     };
   });
 
-  onMount(() => {
+  /// Identity of the profile currently loaded, as an opaque key. A
-    void load();
+  /// plain (non-`$state`) variable on purpose: the effect below reads
+  /// it, and making it reactive would turn "remember what we loaded"
+  /// into a self-write that trips Svelte 5's depth guard — the same
+  /// pattern the banner effect documents around `untrack`.
+  let loadedKey: string | null = null;
+
+  // Reload whenever the profile *identity* changes, not just on
+  // mount. App.svelte keeps this component mounted across a
+  // profile→profile navigation (the view stays `"user"`, only the
+  // props change), so an `onMount`-only load would leave the previous
+  // user's posts and counts on screen under the new name — which is
+  // exactly the path a follower-list or notification click takes.
+  $effect(() => {
+    const key = did ? `did:${did}` : `handle:${handle}`;
+    if (!did && !handle) return;
+    if (loadedKey === key) return;
+    loadedKey = key;
+    untrack(() => void load());
   });
 
   onDestroy(() => {
@@ -299,6 +352,93 @@
 
   type Tab = "posts" | "replies" | "likes";
   let activeTab: Tab = $state("posts");
+
+  // ─── follower / following list ──────────────────────────────────
+  //
+  // Clicking a count opens an inline list under the counts row rather
+  // than navigating away — the user came here for this profile, and a
+  // separate route would cost a second profile fetch on the way back.
+  // Clicking the same count again closes it (the counts double as the
+  // toggle, the way a disclosure does).
+  type ActorListKind = "followers" | "following";
+  let actorKind: ActorListKind | null = $state(null);
+  let actors: ActorProfile[] = $state([]);
+  let actorCursor: string | null = $state(null);
+  let actorLoading: boolean = $state(false);
+  let actorError: string | null = $state(null);
+
+  async function toggleActorList(kind: ActorListKind) {
+    if (actorKind === kind) {
+      closeActorList();
+      return;
+    }
+    if (viewModel.kind !== "ready") return;
+    const did = viewModel.data.did;
+    actorKind = kind;
+    actors = [];
+    actorCursor = null;
+    actorError = null;
+    actorLoading = true;
+    try {
+      const r =
+        kind === "followers"
+          ? await fetchFollowers(did, null, 30)
+          : await fetchFollowing(did, null, 30);
+      // Guard against a fast double-click on the other count: only
+      // commit if we're still the list the user asked for.
+      if (actorKind !== kind) return;
+      actors = r.profiles;
+      actorCursor = r.cursor;
+    } catch (e) {
+      if (actorKind === kind) actorError = String(e);
+    } finally {
+      if (actorKind === kind) actorLoading = false;
+    }
+  }
+
+  async function loadMoreActors() {
+    if (viewModel.kind !== "ready") return;
+    const kind = actorKind;
+    if (!kind || !actorCursor || actorLoading) return;
+    const did = viewModel.data.did;
+    actorLoading = true;
+    try {
+      const r =
+        kind === "followers"
+          ? await fetchFollowers(did, actorCursor, 30)
+          : await fetchFollowing(did, actorCursor, 30);
+      if (actorKind !== kind) return;
+      // De-dupe on DID — a follow edge indexed between two page
+      // fetches can otherwise repeat a row across the boundary.
+      const seen = new Set(actors.map((a) => a.did));
+      actors = [...actors, ...r.profiles.filter((a) => !seen.has(a.did))];
+      actorCursor = r.cursor;
+    } catch (e) {
+      if (actorKind === kind) actorError = String(e);
+    } finally {
+      if (actorKind === kind) actorLoading = false;
+    }
+  }
+
+  function closeActorList() {
+    actorKind = null;
+    actors = [];
+    actorCursor = null;
+    actorError = null;
+    actorLoading = false;
+  }
+
+  // Switching to another profile must not leave the previous user's
+  // follower list on screen. Keyed on the same `(did, handle)`
+  // identity the load effect uses, so the two can't disagree about
+  // when "the profile changed".
+  let actorListKey: string | null = null;
+  $effect(() => {
+    const key = did ? `did:${did}` : `handle:${handle}`;
+    if (actorListKey === key) return;
+    actorListKey = key;
+    untrack(() => closeActorList());
+  });
 </script>
 
 <section class="profile">
@@ -426,17 +566,105 @@
         <dt>posts</dt>
         <dd>{viewModel.data.post_count}</dd>
       </div>
+      <!--
+        The follower / following counts are buttons: they open the
+        matching actor list inline (and close it on a second click).
+        The post count stays inert — there's no endpoint behind it
+        that the feed below doesn't already show.
+
+        The button lives *inside* the `<dd>` rather than wrapping the
+        `dt`/`dd` pair, because a `<dl>` may only contain `dt`/`dd`
+        (via an optional `div`) — a button in between would be invalid
+        markup. `aria-label` puts the term back on the control so a
+        screen reader still hears "followers", not a bare number.
+      -->
       <div>
         <dt>followers</dt>
-        <dd>{viewModel.data.followers}</dd>
+        <dd>
+          <button
+            class="profile__count-btn"
+            class:profile__count-btn--open={actorKind === "followers"}
+            type="button"
+            aria-expanded={actorKind === "followers"}
+            aria-label={`${viewModel.data.followers} followers anzeigen`}
+            onclick={() => void toggleActorList("followers")}
+          >{viewModel.data.followers}</button>
+        </dd>
       </div>
       <div>
         <dt>following</dt>
-        <dd>{viewModel.data.following}</dd>
+        <dd>
+          <button
+            class="profile__count-btn"
+            class:profile__count-btn--open={actorKind === "following"}
+            type="button"
+            aria-expanded={actorKind === "following"}
+            aria-label={`${viewModel.data.following} following anzeigen`}
+            onclick={() => void toggleActorList("following")}
+          >{viewModel.data.following}</button>
+        </dd>
       </div>
     </dl>
   {/if}
 
+  <!-- ─── follower / following list ─────────────────────────────── -->
+  {#if actorKind}
+    <div class="actors">
+      <header class="actors__head">
+        <span class="actors__title">// {actorKind}</span>
+        <button
+          class="actors__close"
+          type="button"
+          onclick={closeActorList}
+        >close</button>
+      </header>
+      {#if actorError}
+        <div class="actors__err">err: {actorError}</div>
+      {/if}
+      {#if actorLoading && actors.length === 0}
+        <div class="actors__empty">// loading…</div>
+      {:else if actors.length === 0}
+        <div class="actors__empty">// niemand hier.</div>
+      {:else}
+        <ul class="actors__list">
+          {#each actors as a (a.did)}
+            <li>
+              <button
+                class="actors__row"
+                type="button"
+                title={a.did}
+                onclick={() => on_actor_click?.(a.did, a.handle)}
+              >
+                <Avatar
+                  did={a.did}
+                  cid={a.avatar_cid ?? null}
+                  name={a.display_name ?? a.handle}
+                  size={32}
+                />
+                <span class="actors__names">
+                  <span class="actors__name">{a.display_name ?? a.handle}</span>
+                  <span class="actors__handle">@{a.handle}</span>
+                </span>
+              </button>
+            </li>
+          {/each}
+        </ul>
+        {#if actorCursor}
+          <div class="actors__loadmore">
+            <button
+              class="actors__more"
+              type="button"
+              disabled={actorLoading}
+              onclick={() => void loadMoreActors()}
+            >
+              {actorLoading ? "loading…" : "load more"}
+            </button>
+          </div>
+        {/if}
+      {/if}
+    </div>
+  {/if}
+
   <!-- ─── tabs ──────────────────────────────────────────────────── -->
   <nav class="profile__tabs" aria-label="Profile sections">
     <button
@@ -465,7 +693,17 @@
   <div class="profile__feed">
     {#if viewModel.kind === "ready"}
       {#each viewModel.data.posts as p (p.uri)}
-        <PostCard post={p} on_thread_click={on_thread_click} />
+        <!--
+          The feed's PostCards carry a real `post.did`, so we route
+          their header clicks through the same DID-first path as the
+          actor list rather than through the (possibly decorated)
+          `post.handle`.
+        -->
+        <PostCard
+          post={p}
+          on_thread_click={on_thread_click}
+          on_handle_click={(h) => on_actor_click?.(p.did, h)}
+        />
       {/each}
       {#if viewModel.data.posts.length === 0}
         <div class="profile__empty">// no posts yet.</div>
@@ -705,6 +943,157 @@
     font-variant-numeric: tabular-nums;
   }
 
+  /* The count button inherits the `dd` typography so the clickable
+     followers/following numbers read identically to the inert post
+     count — only the hover/open colour marks them as interactive. */
+  .profile__count-btn {
+    background: none;
+    border: 0;
+    padding: 0;
+    margin: 0;
+    color: inherit;
+    font: inherit;
+    font-variant-numeric: tabular-nums;
+    cursor: pointer;
+    border-bottom: 2px solid transparent;
+    transition:
+      color var(--dur) var(--ease),
+      border-color var(--dur) var(--ease);
+  }
+  .profile__count-btn:hover {
+    color: var(--orange);
+  }
+  .profile__count-btn--open {
+    color: var(--orange);
+    border-bottom-color: var(--orange);
+  }
+
+  /* ─── follower / following list ─────────────────────────── */
+  .actors {
+    border-top: 1px solid var(--line);
+    border-bottom: 1px solid var(--line);
+    background: var(--bg-elev);
+  }
+  .actors__head {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    gap: var(--s-3);
+    padding: var(--s-2) var(--s-4);
+    border-bottom: 1px solid var(--line);
+  }
+  .actors__title {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    color: var(--orange);
+    letter-spacing: var(--tracking-label);
+    font-weight: 700;
+  }
+  .actors__close {
+    background: transparent;
+    border: 1px solid var(--line-2);
+    color: var(--text-dim);
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    padding: 0.2rem 0.6rem;
+    border-radius: var(--r-sm);
+    cursor: pointer;
+    transition:
+      color var(--dur) var(--ease),
+      border-color var(--dur) var(--ease);
+  }
+  .actors__close:hover {
+    color: var(--orange);
+    border-color: var(--orange);
+  }
+  .actors__err {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    color: var(--red);
+    padding: var(--s-2) var(--s-4);
+  }
+  .actors__empty {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    color: var(--text-dim);
+    font-style: italic;
+    padding: var(--s-3) var(--s-4);
+  }
+  .actors__list {
+    list-style: none;
+    margin: 0;
+    padding: 0;
+    /* Cap the inline list so it never pushes the feed off screen —
+       "load more" keeps the rest reachable. */
+    max-height: 320px;
+    overflow-y: auto;
+  }
+  .actors__row {
+    width: 100%;
+    display: flex;
+    align-items: center;
+    gap: var(--s-3);
+    padding: var(--s-2) var(--s-4);
+    background: transparent;
+    border: 0;
+    border-bottom: 1px solid var(--line);
+    text-align: left;
+    cursor: pointer;
+    color: var(--text);
+    transition: background-color var(--dur) var(--ease);
+  }
+  .actors__row:hover {
+    background: var(--orange-8);
+  }
+  .actors__names {
+    display: flex;
+    flex-direction: column;
+    min-width: 0;
+  }
+  .actors__name {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    font-weight: 700;
+    color: var(--text);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+  .actors__handle {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    color: var(--text-dim);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+  .actors__loadmore {
+    display: flex;
+    justify-content: center;
+    padding: var(--s-3);
+  }
+  .actors__more {
+    font-family: var(--font-mono);
+    font-size: var(--fs-50);
+    padding: 0.4rem 0.8rem;
+    border-radius: var(--r-sm);
+    border: 1px solid var(--line-2);
+    background: transparent;
+    color: var(--text-dim);
+    cursor: pointer;
+    transition:
+      color var(--dur) var(--ease),
+      border-color var(--dur) var(--ease);
+  }
+  .actors__more:hover:not(:disabled) {
+    color: var(--orange);
+    border-color: var(--orange);
+  }
+  .actors__more:disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+  }
+
   /* ─── tabs ──────────────────────────────────────────────── */
   .profile__tabs {
     display: flex;

docs/architecture.md

@@ -0,0 +1,253 @@
+# Architektur
+
+Vertiefung zum Überblick im README: wer schreibt was, wo liegen die Daten, und
+auf welchem Weg kommt ein Post vom Client bis in die Timeline zurück.
+
+## Prozesse und Datenflüsse
+
+```
+                        ┌───────────────────────────────────┐
+                        │  Tauri-Client (Desktop)           │
+                        │  Svelte 5 (Webview)               │
+                        │       │ invoke()                  │
+                        │  src-tauri (Rust-IPC)             │
+                        │   pds_client.rs  appview_client.rs│
+                        └───────┬───────────────────┬───────┘
+                     Schreiben  │                   │  Lesen
+                     XRPC/HTTPS │                   │  REST/HTTP
+                                ▼                   ▼
+    ┌──────────────────────────────────┐   ┌──────────────────────────────┐
+    │ pds-server  (axum, :2583)        │   │ appview  (axum, :2584)       │
+    │                                  │   │                              │
+    │  /xrpc/com.atproto.*             │   │  GET /api/timeline/home  🔒  │
+    │  /xrpc/app.bsky.actor.profile.*  │   │  GET /api/profile[/:handle]  │
+    │  /blob/:cid                      │   │  GET /api/search             │
+    │  /healthz                        │   │  GET /api/post|thread/*uri   │
+    │  /.well-known/did.json ──────────┼───┼─▶ Schlüssel für 🔒           │
+    │                                  │   │  GET /api/notifications…  🔒 │
+    │                                  │   │  GET /api/followers|following│
+    │                                  │   │  GET /healthz                │
+    │  at-lexicon  Validierung (160)   │   │                              │
+    │  at-repo/at-mst  MST + Commit    │   │  indexer.rs  Upserts         │
+    │  at-crypto   Signatur, CID, JWT  │   │  handle_sync.rs  Worker      │
+    │  at-identity PLC / did:web       │   │  ingest.rs   interner Writer │
+    │  at-blob     MinIO               │   │                              │
+    └───┬────────────┬───────────┬─────┘   └──────┬──────────────┬────────┘
+        │            │           │                │              ▲
+        │            │           │  POST /internal/ingest-commit │
+        │            │           └───────────────────────────────┤
+        │            │                            │              │
+        ▼            ▼                            ▼              │
+  ┌───────────┐  ┌────────┐              ┌─────────────────┐     │
+  │ Postgres  │  │ MinIO  │              │ Postgres        │     │
+  │ pds :5434 │  │ :9100  │              │ appview :5435   │     │
+  └───────────┘  └────────┘              └─────────────────┘     │
+        │                                                        │
+        │  (heute: kein eigener Firehose-Ausgang)                 │
+        ▼                                                        │
+   ┌──────────────────────────────────────────┐                  │
+   │ Jetstream-Relay (extern, WebSocket)      │──────────────────┘
+   │ JETSTREAM_URL                            │   at-firehose
+   └──────────────────────────────────────────┘   JetstreamConsumer
+```
+
+🔒 = Bearer-Token nötig, und der `sub` des Tokens muss der angefragten DID
+entsprechen. Die AppView verifiziert die ES256-Signatur mit dem öffentlichen
+Schlüssel, den die PDS in ihrem DID-Dokument veröffentlicht — `PDS_JWT_SECRET`
+verlässt die PDS nie. Details in [`deployment.md`](deployment.md), Abschnitt 6.
+
+Zwei Wege führen in die AppView, und das ist Absicht:
+
+1. **Direkter Push (schnell, lokal).** Jeder erfolgreiche Commit auf der PDS
+   wird per `POST /internal/ingest-commit` an die AppView geschoben
+   (`crates/pds-server/src/appview_push.rs`). Best effort, 5 s Timeout, blockiert
+   den Record-Write nie. Damit sieht der Nutzer seinen eigenen Post sofort.
+2. **Jetstream (global, verzögert).** `at-firehose::JetstreamConsumer` hängt an
+   einem externen Jetstream-Relay und liefert alles, was in den konfigurierten
+   Collections weltweit passiert.
+
+Wichtig für das Verständnis der Topologie: **die eigene PDS speist den
+Jetstream nicht.** Es gibt keinen `com.atproto.sync.subscribeRepos`-Endpoint im
+PDS-Router. Der Firehose-Weg ist ein reiner Konsum-Pfad für fremde Repos; die
+eigenen Records erreichen die AppView ausschließlich über den Push aus
+Punkt 1 (noch offen).
+
+## Crates
+
+| Crate | Typ | Aufgabe |
+|---|---|---|
+| `at-lexicon` | lib | Lexicon-Schemas laden (`Lex::from_json`) und Records validieren. `LexRegistry` in der PDS kennt `app.twi.post` (160 Zeichen), `app.bsky.feed.like`, `app.bsky.feed.repost`, `app.bsky.actor.profile` — alle vier per `include_str!` einkompiliert |
+| `at-crypto` | lib | secp256k1/P-256-Keypairs, DAG-CBOR-CIDs, multibase/base58btc, JWT (`issue_jwt` / `verify_jwt`), PLC-Operationen inkl. `did_plc_from_op` |
+| `at-identity` | lib | Handle- und DID-Auflösung. Drei Resolver hinter dem Trait `DidHandleResolver`: `PlcClient` (PLC-Directory), `WebResolver` (`.well-known/did.json`), `PdsHandleResolver` (fragt die lokale PDS) |
+| `at-mst` | lib | Merkle-Search-Tree: Knoten, `split_around`, `wrap_with_split`, spec-konformes `encode_key` |
+| `at-repo` | lib | Repo-Abstraktion über einem `Blockstore`, Commit-Erzeugung + Signatur, TID-Revisionen (`rev.rs`) |
+| `at-blob` | lib | `S3BlobStore` gegen MinIO (unsignierte PUT/GET/DELETE) und `InMemoryBlobStore` (gleiche CID-Semantik, für Tests/Single-Node ohne Objektspeicher), MIME-Sniffing (`infer`), `ping()` für den Startup-Check |
+| `at-firehose` | lib | `JetstreamConsumer`: WebSocket, Collection-Filter, Cursor-Resume, exponentielles Reconnect-Backoff, `connected`-Flag für `/healthz` |
+| `at-shared` | lib | `AppConfig::from_env()`, `AtError` mit HTTP-Status-Mapping, DID- und Zeit-Helfer |
+| `pds-server` | bin | axum-HTTP-PDS. Routen, Auth/JWT, Repo-Writes, Blob-Upload, AppView-Push |
+| `appview` | bin | axum-REST-API + Jetstream-Indexer + Handle-Sync-Worker + interner Ingest-Endpoint |
+| `tauri-app` | bin (eigener Workspace) | Desktop-Client. Svelte-5-Frontend, Rust-IPC-Layer mit HTTP-Clients für PDS und AppView |
+
+`crates/tauri-app/src-tauri/Cargo.toml` deklariert ein eigenes `[workspace]`,
+das Crate ist also **nicht** Teil des Root-Workspaces. `cargo build --workspace`
+im Repo-Root baut den Client nicht mit, und sein Build-Output landet in
+`crates/tauri-app/src-tauri/target/`.
+
+## Schreibpfad: ein Post entsteht
+
+`ComposeBox` → `invoke("post_create")` → `src-tauri/src/lib.rs` →
+`PdsHttpClient::create_record` → `POST /xrpc/com.atproto.repo.createRecord`.
+
+Serverseitig (`crates/pds-server/src/routes/repo.rs` +
+`routes/helpers.rs::apply_repo_write`):
+
+1. `Authorization: Bearer <access_jwt>` prüfen — verifiziert gegen den aus
+   `PDS_JWT_SECRET` abgeleiteten P-256-Serverschlüssel. `claims.sub` muss der
+   `repo`-DID entsprechen.
+2. Lexicon-Validierung über `state.lex` (abschaltbar mit `validate: false` im
+   Request-Body). Hier greift das 160-Zeichen-Limit von `app.twi.post`.
+3. Transaktion öffnen und `SELECT … FROM repos WHERE did = $1 FOR UPDATE` —
+   der Row-Lock serialisiert konkurrierende Writes desselben Repos.
+4. Record als DAG-CBOR kodieren, CID bilden, Block in den Blockstore legen,
+   MST aktualisieren.
+5. `repo.commit()` signiert den neuen Commit mit dem User-Signing-Key; `rev`
+   ist eine TID.
+6. Blocks + neuer Head landen in `repo_blocks` / `repos`, Commit der
+   Transaktion.
+7. Antwort mit `uri` (`at://did/collection/rkey`), `cid` und dem Commit-Objekt.
+8. Danach — außerhalb des kritischen Pfads — der Push an die AppView.
+
+Der Blockstore in `AppState` ist ein `MemoryBlockstore`; Persistenz kommt aus
+`repo_blocks`. Nach einem Neustart wird der Speicher pro Write aus der DB
+rehydriert.
+
+## Lesepfad: die Timeline
+
+`GET /api/timeline/home?did=…&limit=…&cursor=…`
+(`crates/appview/src/routes.rs`):
+
+1. `SELECT subject_did FROM follows WHERE follower_did = $1`.
+2. Zielmenge = Followees + eigene DID, dedupliziert, auf
+   `MAX_FOLLOWED_DIDS = 1000` gedeckelt (sortiert, damit die Kürzung stabil
+   ist; die eigene DID bleibt garantiert drin).
+3. Ist die Menge leer bzw. nur die eigene DID, fällt die Abfrage auf den
+   globalen Recent-Feed zurück — Cold-Start für neue Accounts.
+4. Posts aus `posts` mit
+   `collection IN ('app.twi.post','app.bsky.feed.post')`.
+5. Paginierung über einen opaken Cursor `base64url(micros):uri`
+   (`routes/cursor.rs`), passend zu den Indizes aus
+   `0002_pagination_indexes.sql`.
+6. `decorate_handles` ersetzt leere Handles anzeigeseitig durch
+   `@<erste-12-Zeichen-der-DID>…` — die DB-Zeile bleibt unangetastet, das
+   Nachfüllen erledigt der Handle-Sync-Worker.
+
+Limits: Default 30, Maximum 100.
+
+Die vollständige, aktuelle Routenliste steht in
+`crates/appview/src/routes.rs::router` — sie wächst gerade (Thread-Kontext,
+Notifications, Follower-Listen) und wird hier bewusst nicht dupliziert.
+
+## Indexer
+
+`crates/appview/src/firehose.rs` ist der Event-Dispatcher, `indexer.rs` macht
+die Schreibarbeit. Behandelte Event-Arten:
+
+* `commit` → `apply_commit`, dispatcht auf die Collection:
+  `app.twi.post` / `app.bsky.feed.post`, `app.bsky.feed.like`,
+  `app.bsky.feed.repost`, `app.bsky.graph.follow`, `app.bsky.actor.profile`.
+  Alles andere wird übersprungen (der Cursor darf trotzdem weiterlaufen).
+* `identity` → `backfill_handle`: schreibt den neuen Handle in alle
+  `posts`-Zeilen der DID.
+* `account` → `handle_account`.
+
+Alle Schreibpfade sind Upserts, das Replay nach einem Reconnect ist damit
+unschädlich. Fehlerhafte Events rücken den Cursor **nicht** vor.
+
+`ingest.rs` bedient denselben Indexer über HTTP, mit den Aktionen
+`create` / `delete`; für `app.bsky.graph.follow`-Deletes braucht der Aufrufer
+`subject_did` im Body, weil der Record-Wert bei Deletes nicht garantiert
+mitkommt.
+
+## Datenbanken und Tabellen
+
+### PDS-DB (`DATABASE_URL_PDS`, Compose-Port 5434)
+
+| Tabelle | Inhalt |
+|---|---|
+| `users` | `did` (PK), `handle` (unique), `email`, `password_hash` (argon2id), `signing_key`, `rotation_key` |
+| `repos` | Ein Head pro DID: `rev` (TID), `head_cid`, `head_commit` (CBOR), `prev_commit` |
+| `repo_blocks` | `(did, cid)` → CBOR-Block. MST-Knoten **und** Records. `0002_blob_mime.sql` ergänzt einen `cid`-Index |
+| `blobs` | `cid` (PK), `did`, `mime_type`, `size`, `storage_key` (S3-Key) |
+| `sessions` | Access-/Refresh-JWT mit Ablaufzeiten und `revoked_at` |
+| `plc_ops` | Audit-Log der signierten PLC-Operationen, `submitted`-Flag |
+
+Trigger `users_touch` pflegt `users.updated_at`.
+
+### AppView-DB (`DATABASE_URL_APPVIEW`, Compose-Port 5435)
+
+Stand der Migrationen zum Zeitpunkt dieses Dokuments; maßgeblich bleibt
+`migrations/appview/`.
+
+| Tabelle | Inhalt |
+|---|---|
+| `posts` | `uri` (PK), `did`, `handle`, `rkey`, `collection`, `text`, `cid`, `parent_uri`, `root_uri`, `langs`, `created_at`, `indexed_at`. Später ergänzt: `embed` (JSONB), `reply_parent_handle`, `reply_root_handle`, `reply_root_uri` (0003), `like_count`, `repost_count` (0004), `avatar_cid` (0005), `handle_sync_attempted_at` (0006) |
+| `likes` / `reposts` | `uri` (PK), `did`, `post_uri`, `post_cid`. `0004_like_repost_counters.sql` ergänzt je einen Unique-Index auf `(did, post_uri)` gegen Doppel-Likes und dedupliziert vorhandene Zeilen. Die Zähler auf `posts` pflegt der Indexer selbst (`UPDATE posts SET like_count = like_count + 1 …`, beim Entfernen mit `GREATEST(…, 0)`) — es gibt keine DB-Trigger dafür |
+| `follows` | `(follower_did, subject_did)` als PK — die Basis des Timeline-Filters |
+| `profiles` | `did` (PK), `handle`, `display_name`, `description`, `avatar_cid`, `banner_cid`, drei Counter. Angelegt in `0005_profiles.sql` inkl. Backfill aus `posts` |
+| `jetstream_cursor` | Genau eine Zeile (`id = 1`), `cursor` = Mikrosekunden seit Epoch |
+| `timeline_cache` | In `0001_init.sql` angelegt, aber von keinem Code-Pfad gelesen oder geschrieben — Platzhalter für materialisierte Timelines |
+
+Suche läuft über den Trigram-GIN-Index `posts_text_trgm_idx` (`pg_trgm`), nicht
+über Full-Text-Search.
+
+### MinIO
+
+Zwei Buckets aus dem Compose-Init: `maarcadetweet-pds` und
+`maarcadetweet-appview`. Genutzt wird faktisch nur der erste — `S3_BUCKET_APPVIEW`
+ist zwar Pflichtvariable in `AppConfig`, wird aber von keinem Code-Pfad gelesen.
+`at-blob` spricht MinIO ohne Signature V4, die Buckets brauchen deshalb
+`anonymous download`.
+
+Blobs sind doppelt referenziert: der Objekt-Key liegt in `blobs.storage_key`,
+zusätzlich hält die PDS den Block im lokalen Blockstore. Fällt MinIO aus, kann
+`uploadBlob` weiterlaufen und `GET /blob/:cid` aus dem lokalen Bestand bedienen
+(die Startup-Warnung sagt genau das).
+
+## Identität
+
+* `createAccount` erzeugt zwei secp256k1-Keypairs (Signing + Rotation), baut
+  daraus eine `PlcOperation`, signiert sie und leitet die DID **deterministisch
+  aus der CID der signierten Op** ab (`did_plc_from_op`).
+* Das Submit ans PLC-Directory ist best effort. Schlägt es fehl, bleibt die DID
+  lokal gültig — sie ist dann nur global nicht auflösbar
+  (`plc submit failed (dev ok)` im Log).
+* `com.atproto.identity.resolveHandle` ist polymorph: beginnt der Wert mit
+  `did:`, wird per Primärschlüssel in `users` gesucht, sonst über den Handle
+  (mit Suffix-Matching gegen `PDS_HANDLE_DNS_ZONE`). Genau diesen Pfad nutzt
+  der `PdsHandleResolver` der AppView, damit lokale Nutzer — auch
+  `did:key:`-Accounts — ohne Umweg über plc.directory einen Handle bekommen.
+* Reihenfolge im Handle-Sync-Worker: lokale PDS → PLC → `did:web`. Andere
+  DID-Methoden werden übersprungen.
+
+## Client
+
+Der Webview ruft nie direkt HTTP: die CSP erlaubt `connect-src 'self' ipc:
+http://ipc.localhost`, alle Netzwerkaufrufe laufen über `invoke()` in den
+Rust-Layer (`pds_client.rs` für Schreiben/Auth, `appview_client.rs` für Lesen).
+`store.rs` hält die Session.
+
+Die Backend-URLs kommen aus `MAARCADETWEET_PDS_URL` und
+`MAARCADETWEET_APPVIEW_URL` mit den Defaults `http://127.0.0.1:2583` und
+`http://127.0.0.1:2584`; sie werden beim Start in `AppState` eingefroren und
+sind zur Laufzeit nicht umschaltbar.
+
+Registrierte Tauri-Plugins: `notification`, `dialog`, `shell`, `updater`,
+`window-state`. Die Capability `default` (`capabilities/default.json`) gibt dem
+`main`-Window unter anderem `updater:default` frei — der Updater ist damit
+vorbereitet, aber in `tauri.conf.json` deaktiviert (siehe
+[tauri-release.md](tauri-release.md)).
+
+## Lesehinweise für den Betrieb
+
+Ports, Umgebungsvariablen, Health-Checks und das Neustart-Verhalten des
+Jetstream-Cursors stehen in [deployment.md](deployment.md).

docs/deployment.md

@@ -0,0 +1,583 @@
+# Deployment
+
+Wie der Stack real betrieben wird: zwei Rust-Binaries (`pds-server`, `appview`),
+zwei Postgres-Datenbanken und ein MinIO-Bucket-Paar. Der Tauri-Client wird
+separat gebaut (siehe [tauri-release.md](tauri-release.md)), der Aufbau der
+Komponenten steht in [architecture.md](architecture.md).
+
+## Voraussetzungen
+
+| Komponente | Version | Woher belegt |
+|---|---|---|
+| Rust-Toolchain | ≥ 1.80 | `rust-version` in `Cargo.toml` |
+| Docker + Compose | aktuell | `docker-compose.yml` |
+| PostgreSQL | 16 | `postgres:16-alpine` im Compose-File |
+| MinIO | latest | `minio/minio` im Compose-File |
+| Node + npm | Node 20, npm 10.8.2 | `packageManager` in `crates/tauri-app/package.json` — nur für den Desktop-Client nötig |
+
+Ein C-Compiler/Linker wird für `rusqlite` (Feature `bundled`) und die
+Crypto-Crates gebraucht.
+
+## 1. Infrastruktur starten
+
+```bash
+docker compose up -d
+```
+
+Das Compose-File startet vier Container:
+
+| Container | Dienst | Host-Port | Zugangsdaten (Default) |
+|---|---|---|---|
+| `maarcadetweet-pds-db` | Postgres für die PDS | `5434` → 5432 | `pds` / `pds`, DB `pds` |
+| `maarcadetweet-appview-db` | Postgres für die AppView | `5435` → 5432 | `appview` / `appview`, DB `appview` |
+| `maarcadetweet-minio` | S3-kompatibler Blob-Store | `9100` (API), `9101` (Konsole) | `minioadmin` / `minioadmin` |
+| `maarcadetweet-minio-init` | Einmal-Job | — | legt die Buckets an und beendet sich |
+
+`minio-init` legt `maarcadetweet-pds` und `maarcadetweet-appview` an und setzt
+beide auf `anonymous download`. Das ist kein Zufall: `at-blob` liest Blobs über
+ein einfaches `GET ${endpoint}/${bucket}/${key}` ohne Signatur.
+
+Alle drei Langläufer haben Healthchecks (`pg_isready` bzw.
+`/minio/health/live`), Zustand prüfen mit `docker compose ps`.
+
+**Für Produktion ändern:** Die Passwörter im Compose-File sind Dev-Defaults und
+stehen im Klartext. Wer den Stack öffentlich betreibt, ersetzt sie (und die
+korrespondierenden Werte in `.env`) oder betreibt Postgres/MinIO ganz außerhalb
+von Compose. Die Ports 5434/5435/9100/9101 sind auf allen Interfaces gemappt —
+in Produktion auf `127.0.0.1:` binden.
+
+## 2. Migrationen
+
+**Migrationen laufen automatisch beim Start der Binaries.** Es gibt keinen
+separaten Migrationsschritt und kein Skript in `scripts/` (das Verzeichnis ist
+leer).
+
+* `crates/pds-server/src/main.rs`: `sqlx::migrate!("../../migrations/pds").run(&db)`
+* `crates/appview/src/main.rs`: `sqlx::migrate!("../../migrations/appview").run(&db)`
+
+`sqlx::migrate!` ist ein Makro: die `.sql`-Dateien werden **zur Compile-Zeit in
+das Binary eingebettet**. Konsequenzen für den Betrieb:
+
+* Eine neue Migration wird erst nach einem Rebuild wirksam — das Binary allein
+  neu zu starten reicht nicht.
+* Der Migrationsstand liegt in der Tabelle `_sqlx_migrations` der jeweiligen DB.
+  Wird eine bereits angewendete Datei nachträglich geändert, bricht der Start
+  mit einem Checksum-Fehler ab.
+* Die Datenbanken müssen die Extensions `uuid-ossp`, `pgcrypto` (PDS) bzw.
+  `uuid-ossp`, `pg_trgm` (AppView) anlegen dürfen (`CREATE EXTENSION` in
+  `0001_init.sql`). Beim offiziellen Postgres-Image ist der Compose-User
+  Superuser; bei managed Postgres müssen die Extensions vorab freigeschaltet
+  sein.
+* `migrations/appview/0001_init.sql` legt die Cursor-Zeile an
+  (`INSERT INTO jetstream_cursor (id, cursor) VALUES (1, 0)`) — ohne sie fällt
+  die AppView auf Cursor `0` zurück und startet ohne Resume.
+
+Maßgeblich ist immer der Inhalt von `migrations/pds/` bzw.
+`migrations/appview/` — beim Schreiben dieses Dokuments `0001_init` und
+`0002_blob_mime` auf der PDS-Seite, `0001_init` bis `0008_notifications` auf
+der AppView-Seite.
+
+Die Dateinamen folgen dem `<version>_<name>.sql`-Schema von sqlx, ein manueller
+Lauf mit `sqlx-cli` (`sqlx migrate run --source migrations/appview`) ist damit
+prinzipiell kompatibel. `sqlx-cli` ist aber **nicht** Teil des Workspaces und
+wird nirgends im Code oder in CI verwendet — der dokumentierte Weg bleibt der
+automatische Lauf beim Start.
+
+Im Code gibt es keine `sqlx::query!`-Makros (nur die Laufzeit-Varianten
+`sqlx::query` / `query_as` / `query_scalar`). Für den Build wird also **keine**
+erreichbare Datenbank und kein `.sqlx`-Offline-Cache gebraucht.
+
+## 3. Umgebungsvariablen
+
+`cp .env.example .env` und anpassen — das reicht für den Dev-Betrieb. Beide
+Binaries rufen als erstes in `main()` `dotenvy::dotenv()` auf (`dotenvy` ist
+Workspace-Dependency und in `crates/pds-server` wie `crates/appview`
+eingebunden) und laden damit eine `.env` aus dem Arbeitsverzeichnis bzw. den
+übergeordneten Verzeichnissen. **Echte Umgebungsvariablen gewinnen** über die
+Werte aus der Datei; ist keine `.env` vorhanden, passiert schlicht nichts.
+
+Im Serverbetrieb ist die Datei damit optional: systemd (`EnvironmentFile=`)
+oder die Container-Runtime setzen die Variablen direkt, und sie überschreiben
+eine versehentlich mitdeployte `.env`.
+
+### Pflicht (fehlt eine, bricht `AppConfig::from_env()` mit `missing env: X` ab)
+
+Quelle: `crates/at-shared/src/config.rs`. Beide Binaries lesen dieselbe
+`AppConfig`, also braucht **auch die AppView die PDS-Variablen** und umgekehrt.
+
+| Variable | Bedeutung |
+|---|---|
+| `PDS_HOST` | Listen-Adresse der PDS (`format!("{host}:{port}")` → `TcpListener::bind`) |
+| `PDS_PORT` | Listen-Port der PDS, `u16` |
+| `PDS_PUBLIC_URL` | Öffentliche Basis-URL der PDS. Geht in den DID-Doc-`serviceEndpoint` (`routes/auth.rs`), in den JWT-`iss` (`jwt_issuer.rs`), als `public_base` in den Blob-Store und als Fallback für `PDS_INTERNAL_URL` |
+| `PDS_HANDLE_DNS_ZONE` | Handle-Suffix inkl. führendem Punkt, z. B. `.maarcadetweet.local`. Wird in `com.atproto.identity.resolveHandle` beim Suffix-Matching benutzt und (ohne Punkt) als `availableUserDomains` in `describeServer` gemeldet |
+| `PDS_JWT_SECRET` | **Hex-String** (≥ 32 Bytes, gültiger P-256-Skalar), aus dem der Serverschlüssel für die Access-/Refresh-JWTs abgeleitet wird — siehe Fallstricke unten |
+| `APPVIEW_HOST` | Listen-Adresse der AppView |
+| `APPVIEW_PORT` | Listen-Port der AppView, `u16` |
+| `APPVIEW_PUBLIC_URL` | Öffentliche Basis-URL der AppView; die PDS benutzt sie als Fallback-Ziel für den Ingest-Push |
+| `JETSTREAM_URL` | WebSocket-URL des Jetstream-Relays |
+| `JETSTREAM_COLLECTIONS` | Komma-separierte Liste der Collections im `subscribe`-Filter. Leere Einträge werden verworfen |
+| `DATABASE_URL_PDS` | Postgres-DSN der PDS-DB |
+| `DATABASE_URL_APPVIEW` | Postgres-DSN der AppView-DB |
+| `S3_ENDPOINT` | Basis-URL des Blob-Stores (MinIO) |
+| `S3_REGION` | Region-String; wird im aktuellen `at-blob` nur mitgeführt, nicht signiert |
+| `S3_ACCESS_KEY` | MinIO-Access-Key |
+| `S3_SECRET_KEY` | MinIO-Secret-Key |
+| `S3_BUCKET_PDS` | Bucket, in den die PDS Blobs schreibt |
+| `S3_BUCKET_APPVIEW` | Bucket für die AppView — Pflichtfeld in der Config, wird aber von keinem Code-Pfad gelesen |
+| `PLC_DIRECTORY_URL` | PLC-Directory. Die PDS submittet dort neue `did:plc:`-Ops (best effort), die AppView löst darüber Handles auf |
+
+### Optional
+
+| Variable | Default | Bedeutung |
+|---|---|---|
+| `PDS_INTERNAL_URL` | `PDS_PUBLIC_URL` | Cluster-interne PDS-URL, die die AppView für ihren `PdsHandleResolver` nutzt |
+| `APPVIEW_INTERNAL_URL` | `APPVIEW_PUBLIC_URL` | Cluster-interne AppView-URL für den Commit-Push der PDS (`crates/pds-server/src/state.rs`) |
+| `APPVIEW_INGEST_SECRET` | unset | Shared Secret für `POST /internal/ingest-commit`. Unset = Dev-Modus, der Endpoint akzeptiert anonyme Requests. Gesetzt = Header `X-Ingest-Secret` muss (konstantzeitverglichen) passen. Muss auf **beiden** Seiten identisch gesetzt sein |
+| `APPVIEW_HANDLE_SYNC_INTERVAL_SECS` | `300` | Intervall des Handle-Sync-Workers. Nicht parsbare Werte fallen still auf den Default zurück |
+| `RUST_LOG` | `info` | `tracing_subscriber::EnvFilter::try_from_default_env()` in beiden Binaries und im Tauri-Client |
+
+### Nur für den Desktop-Client
+
+Gelesen in `crates/tauri-app/src-tauri/src/lib.rs`:
+
+| Variable | Default |
+|---|---|
+| `MAARCADETWEET_PDS_URL` | `http://127.0.0.1:2583` |
+| `MAARCADETWEET_APPVIEW_URL` | `http://127.0.0.1:2584` |
+
+### Nur für Tests
+
+Die Integrationstests in `crates/appview/tests/` und
+`crates/pds-server/tests/` lesen `DATABASE_URL_APPVIEW` bzw. `DATABASE_URL_PDS`
+direkt und überspringen sich selbst, wenn die Variable fehlt.
+
+### Fallstricke
+
+`.env.example` deckt inzwischen alle Variablen ab, die der Code liest — auch
+die optionalen (`PDS_INTERNAL_URL`, `APPVIEW_INTERNAL_URL`,
+`APPVIEW_HANDLE_SYNC_INTERVAL_SECS`, `APPVIEW_INGEST_SECRET`,
+`MAARCADETWEET_PDS_URL`, `MAARCADETWEET_APPVIEW_URL`), die dort auskommentiert
+mit ihrem Default stehen. Zwei Punkte bleiben trotzdem erklärungsbedürftig:
+
+1. **`PDS_JWT_SECRET` ist kein beliebiger String, sondern ein P-256-Skalar.**
+   `jwt_issuer.rs::server_p256_keypair` macht
+   `hex::decode(secret.trim_start_matches("0x"))`, verlangt ≥ 32 Bytes und
+   gibt die ersten 32 Bytes an `p256::SecretKey::from_bytes()`. Der Wert muss
+   also **Hex sein und ein gültiger Skalar der P-256-Kurve** — lauter Nullen
+   (oder ein Wert ≥ Gruppenordnung) wird abgelehnt.
+
+   Der Fehler zeigt sich spät und breit: Der Prozess **startet normal**, weil
+   der Schlüssel erst beim ersten Zugriff abgeleitet wird. Danach antwortet
+   aber alles mit `500`, was `server_p256_public_multibase` bzw.
+   `server_p256_keypair` benutzt — nicht nur
+   `createAccount` / `createSession` / `refreshSession` (`routes/auth.rs`),
+   sondern auch jeder Record-Write, weil dort der Access-Token gegen genau
+   diesen Serverschlüssel verifiziert wird: `routes/repo.rs`,
+   `routes/feed.rs`, `routes/blob.rs`, `routes/profile.rs`.
+
+   `.env.example` enthält einen gültigen Zufallswert als Beispiel. Für jede
+   echte Instanz einen eigenen erzeugen:
+
+   ```bash
+   openssl rand -hex 32
+   ```
+
+2. **`S3_BUCKET_APPVIEW` ist Pflicht, aber ungenutzt.** `AppConfig` verlangt
+   die Variable, kein Code-Pfad greift auf `cfg.s3_bucket_appview` zu. Der
+   Wert muss trotzdem gesetzt sein, sonst startet keins der Binaries.
+   (In `.env.example` ist das entsprechend vermerkt.)
+
+Beachtenswert bleibt außerdem `JETSTREAM_COLLECTIONS`: Die Liste in
+`.env.example` enthält jetzt alle Collections, die der Indexer kennt —
+`app.twi.post` (das eigene 160-Zeichen-Lexicon, `POST_COLLECTIONS` in
+`crates/appview/src/indexer.rs`), `app.bsky.feed.post`, `app.bsky.feed.like`,
+`app.bsky.feed.repost`, `app.bsky.graph.follow` und
+`app.bsky.actor.profile`. Wird `app.twi.post` daraus entfernt, tauchen eigene
+Posts nur noch über den direkten PDS→AppView-Push auf, nicht über den
+Firehose-Weg.
+
+## 4. Release-Build
+
+```bash
+cargo build --release -p pds-server -p appview
+```
+
+Ergebnis: `target/release/pds-server` und `target/release/appview`. Das
+Release-Profil im Workspace-`Cargo.toml` setzt `lto = "thin"`,
+`codegen-units = 1`, `opt-level = 3`, `strip = true` — die Binaries sind ohne
+Debug-Symbole, für Crash-Analysen also vorher separat sichern.
+
+Da die Migrationen einkompiliert werden, gehören `migrations/` und die
+`lexicons/*.json` (via `include_str!` in `crates/pds-server/src/state.rs`) zum
+Build-Input, nicht zum Laufzeit-Deployment. Auf dem Zielhost muss nur das
+Binary liegen.
+
+## 5. systemd
+
+Beispiel für einen Host, auf dem die Binaries unter `/opt/maarcadetweet/bin`
+liegen und `/etc/maarcadetweet/env` die Variablen aus Abschnitt 3 enthält
+(Modus `0600`, wegen `PDS_JWT_SECRET` und `APPVIEW_INGEST_SECRET`).
+
+`/etc/systemd/system/maarcadetweet-pds.service`:
+
+```ini
+[Unit]
+Description=maarcadetweet PDS
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=maarcadetweet
+Group=maarcadetweet
+EnvironmentFile=/etc/maarcadetweet/env
+ExecStart=/opt/maarcadetweet/bin/pds-server
+Restart=on-failure
+RestartSec=5
+# Logs gehen über tracing auf stdout/stderr ins Journal
+StandardOutput=journal
+StandardError=journal
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=true
+
+[Install]
+WantedBy=multi-user.target
+```
+
+`/etc/systemd/system/maarcadetweet-appview.service`:
+
+```ini
+[Unit]
+Description=maarcadetweet AppView
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=maarcadetweet
+Group=maarcadetweet
+EnvironmentFile=/etc/maarcadetweet/env
+ExecStart=/opt/maarcadetweet/bin/appview
+Restart=on-failure
+RestartSec=5
+StandardOutput=journal
+StandardError=journal
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=true
+
+[Install]
+WantedBy=multi-user.target
+```
+
+Hinweise:
+
+* Beide Units brauchen dieselbe `EnvironmentFile` — beide Binaries bauen die
+  vollständige `AppConfig`.
+* `dotenvy::dotenv()` sucht die `.env` ab dem Arbeitsverzeichnis aufwärts.
+  Ohne `WorkingDirectory=` ist das unter systemd `/`, es wird also keine
+  gefunden — die `EnvironmentFile` ist die einzige Quelle. Läge doch eine
+  `.env` im Arbeitsverzeichnis, hätten die systemd-Variablen trotzdem Vorrang.
+* `Type=simple` ist korrekt: keins der Binaries forkt oder meldet Readiness.
+  Eine `Type=notify`-Integration existiert nicht.
+* Es gibt **keinen** Signal-Handler für graceful Shutdown. `systemctl stop`
+  beendet den Prozess hart; bei der AppView bedeutet das, dass der letzte
+  Cursor-Flush nur passiert, wenn der Kanal regulär geschlossen wird —
+  praktisch also mit bis zu 100 Events Verlust (siehe Abschnitt 9). Das ist
+  unkritisch, weil der Cursor beim Resume ohnehin leicht in die Vergangenheit
+  zeigt und Events idempotent verarbeitet werden.
+* Eine Abhängigkeit `After=` auf Postgres/MinIO ist nur nötig, wenn diese auf
+  demselben Host laufen. Die AppView bricht beim Start ab, wenn ihre DB nicht
+  erreichbar ist (`PgPool::connect` ohne Retry); die PDS nutzt
+  `PgPoolOptions` mit `acquire_timeout(10s)`, bricht aber ebenfalls ab, wenn
+  der erste Connect scheitert. `Restart=on-failure` fängt das ab.
+
+## 6. Authentifizierung
+
+Die AppView prüft seit Phase 9 Bearer-Tokens. Wie das zusammenhängt:
+
+1. Die PDS stellt beim Login ein ES256-Access-JWT aus (`sub` = DID,
+   `scope` = `com.atproto.access`, eine Stunde gültig).
+2. Die PDS veröffentlicht den *öffentlichen* Teil ihres P-256-Schlüssels unter
+   `GET /.well-known/did.json`. `PDS_JWT_SECRET` verlässt den PDS-Prozess nicht.
+3. Die AppView holt dieses Dokument beim Start von `PDS_INTERNAL_URL`
+   (Fallback: `PDS_PUBLIC_URL`), cached den Schlüssel und lädt ihn bei einem
+   Verifikationsfehler einmal nach — höchstens einmal pro Minute, damit
+   Müll-Tokens kein Werkzeug werden, die PDS zu fluten. Ein Schlüsselwechsel
+   braucht also keinen Neustart der AppView.
+
+Ist die PDS beim Start nicht erreichbar, warnt die AppView nur und startet
+trotzdem — sie indiziert den Firehose, was von der lokalen PDS unabhängig ist.
+Der Schlüssel wird dann beim ersten authentifizierten Request geholt. Klappt
+auch das nicht, antwortet sie `503 AuthUnavailable`: **fail closed**, nie
+fail open.
+
+### Welche Endpoints
+
+| Endpoint | Zugriff |
+|---|---|
+| `/api/timeline/home`, `/api/notifications`, `/api/notifications/count`, `/api/notifications/seen` | Token nötig, `sub` muss dem `did`-Parameter entsprechen |
+| `/api/profile*`, `/api/search`, `/api/post/*`, `/api/thread*`, `/api/followers`, `/api/following` | öffentlich (in AT Proto öffentliche Records) |
+| `/internal/ingest-commit` | `APPVIEW_INGEST_SECRET`, server-zu-server |
+
+### Fehlercodes
+
+| Fall | Status | `error` |
+|---|---|---|
+| Header fehlt oder ist kein Bearer | 401 | `AuthMissing` |
+| Signatur falsch, abgelaufen, falscher `scope` | 401 | `TokenInvalid` |
+| Token gültig, aber `sub` ≠ `did` | 403 | `Forbidden` |
+| Schlüssel der PDS nicht beschaffbar | 503 | `AuthUnavailable` |
+
+`TokenInvalid` ist ein Vertrag mit dem Desktop-Client: daran erkennt er, dass
+er sein Access-JWT erneuern und den Request einmal wiederholen muss. Wer den
+Code umbenennt, loggt jeden Nutzer eine Stunde nach dem Login aus.
+
+### `APPVIEW_AUTH_REQUIRED=false`
+
+Schaltet die Prüfung ab und stellt das alte Verhalten her — gedacht für eine
+Instanz hinter VPN und für die fail-open-Integrationstests. Die AppView warnt
+beim Start in Großbuchstaben. Öffentlich erreichbar heißt das: jeder kann die
+Notifications jeder DID lesen und als gelesen markieren.
+
+## 7. Reverse-Proxy
+
+### PDS
+
+Die PDS muss öffentlich erreichbar sein, damit andere AT-Protocol-Dienste und
+der Client sie ansprechen können. Routen aus `crates/pds-server/src/main.rs`:
+
+```
+GET  /
+GET  /healthz
+GET  /xrpc/com.atproto.server.describeServer
+POST /xrpc/com.atproto.server.createAccount
+POST /xrpc/com.atproto.server.createSession
+POST /xrpc/com.atproto.server.refreshSession
+POST /xrpc/com.atproto.identity.resolveHandle
+POST /xrpc/com.atproto.repo.createRecord
+POST /xrpc/com.atproto.repo.deleteRecord
+POST /xrpc/com.atproto.feed.like.create
+POST /xrpc/com.atproto.uploadBlob
+GET  /xrpc/com.atproto.sync.getRepo
+GET  /xrpc/com.atproto.sync.getBlocks
+GET  /xrpc/com.atproto.sync.getLatestCommit
+GET  /xrpc/com.atproto.sync.getRecord
+GET  /xrpc/com.atproto.sync.listRepos
+GET  /xrpc/com.atproto.sync.getBlob
+GET  /xrpc/app.bsky.actor.profile.get
+POST /xrpc/app.bsky.actor.profile.set
+GET  /blob/:cid
+```
+
+nginx-Skizze:
+
+```nginx
+server {
+    listen 443 ssl http2;
+    server_name pds.example.org;
+
+    # TLS-Konfiguration hier
+
+    location / {
+        proxy_pass         http://127.0.0.1:2583;
+        proxy_http_version 1.1;
+        proxy_set_header   Host              $host;
+        proxy_set_header   X-Forwarded-Proto $scheme;
+        proxy_set_header   X-Forwarded-For   $proxy_add_x_forwarded_for;
+
+        # uploadBlob: MAX_BLOB_SIZE in routes/blob.rs ist 1 MiB.
+        # Der Proxy darf nicht enger sein, sonst kommt statt der
+        # XRPC-Fehlerantwort ein nginx-413 beim Client an.
+        client_max_body_size 1m;
+    }
+}
+```
+
+`PDS_PUBLIC_URL` muss auf genau diese öffentliche URL zeigen — der Wert landet
+im DID-Doc-`serviceEndpoint`, im JWT-`iss` und als Basis der Blob-URLs.
+
+**Noch offen:** Die PDS liefert selbst **kein** `/.well-known/did.json` und
+kein `/.well-known/atproto-did` aus (im Router nicht vorhanden). `at-identity`
+kann solche Dokumente *auflösen*, aber wer `did:web`-Handles auf dieser PDS
+betreiben will, muss die Dateien vorerst statisch über den Proxy ausliefern.
+Die Service-DID wird inzwischen aus `PDS_PUBLIC_URL` abgeleitet
+(`AppConfig::pds_did()`, did:web mit `%3A`-kodiertem Port) und von
+`describeServer` **und** `/.well-known/did.json` identisch ausgeliefert. Das
+heißt auch: ändert sich `PDS_PUBLIC_URL`, ändert sich die Service-DID.
+
+### AppView
+
+Die AppView setzt ihr CORS selbst (`cors_layer()` in
+`crates/appview/src/routes.rs`). Ohne `APPVIEW_CORS_ORIGINS` bleibt es beim
+alten `Access-Control-Allow-Origin: *` — die AppView warnt dann beim Start.
+Mit gesetzter Variable gilt eine Allowlist:
+
+```
+APPVIEW_CORS_ORIGINS=tauri://localhost,http://tauri.localhost,http://127.0.0.1:1430
+```
+
+Der Tauri-Webview ruft die AppView von einem anderen Origin aus auf — im Dev
+die Vite-Adresse, im Bundle `tauri://localhost` (macOS/Linux) bzw.
+`http://tauri.localhost` (Windows). Alle drei gehören in die Liste, sonst
+scheitert der Preflight.
+
+`/internal/ingest-commit` liegt bewusst **außerhalb** der CORS-Schicht: die
+Route wird von der PDS server-zu-server aufgerufen, nie von einem Browser. Ein
+`Access-Control-Allow-Origin` darauf würde ausschließlich einer Webseite
+helfen, in den Index zu schreiben.
+
+Für ein öffentliches Deployment heißt das:
+
+* `POST /internal/ingest-commit` gehört **nicht** ins Internet. Entweder im
+  Proxy blocken (`location /internal/ { deny all; }`) oder die AppView nur auf
+  dem internen Interface lauschen lassen und den Public-Vhost nur auf `/api/`
+  und `/healthz` mappen.
+* `APPVIEW_INGEST_SECRET` setzen, sobald die AppView irgendwie erreichbar ist —
+  ohne das Secret ist der Ingest-Endpoint unauthentifiziert.
+* Wer den Wildcard-Origin einschränken will, muss den Header im Proxy
+  überschreiben, nicht nur ergänzen — sonst stehen zwei Werte drin:
+
+```nginx
+location /api/ {
+    proxy_pass http://127.0.0.1:2584;
+    proxy_hide_header Access-Control-Allow-Origin;
+    add_header Access-Control-Allow-Origin "tauri://localhost" always;
+}
+
+location /internal/ { deny all; }
+```
+
+Eine Konfigurierbarkeit der erlaubten Origins über eine Umgebungsvariable gibt
+es im Code **nicht** — das ist noch offen.
+
+### CSP im Client
+
+`tauri.conf.json` setzt `connect-src 'self' ipc: http://ipc.localhost`. Die
+HTTP-Aufrufe an PDS/AppView laufen über den Rust-IPC-Layer
+(`src-tauri/src/pds_client.rs`, `appview_client.rs`), nicht aus dem Webview —
+die CSP muss also für neue Backend-URLs nicht angefasst werden.
+
+## 8. Health-Checks und Logs
+
+### PDS
+
+```
+GET /healthz  →  {"ok": true}
+GET /          →  {"name":"maarcadetweet-pds","version":"0.1.0"}
+```
+
+`/healthz` ist ein reiner Liveness-Probe ohne DB-Zugriff — ein `200` bedeutet
+nicht, dass Postgres erreichbar ist.
+
+Beim Start pingt die PDS zusätzlich MinIO (`S3BlobStore::ping`, ein `HEAD` auf
+`${S3_ENDPOINT}/${S3_BUCKET_PDS}`; `2xx` und `404` gelten als erreichbar). Ein
+Fehlschlag ist **kein** Startabbruch, sondern eine Warnung:
+
+```
+s3 ping failed at startup; uploadBlob will serve from local blockstore only
+```
+
+### AppView
+
+```
+GET /healthz  →  {"ok":true,"lag_ms":…,"events_processed":…,"jetstream_connected":…}
+GET /          →  {"name":"maarcadetweet-appview","version":"0.1.0"}
+```
+
+Diese drei Felder sind der eigentliche Monitoring-Hook:
+
+* `jetstream_connected` — `false` heißt: WebSocket ist weg, der Consumer
+  reconnectet mit Backoff (1 s, verdoppelnd bis `max_backoff_secs = 30`).
+* `events_processed` — monoton steigender Zähler. Stagniert er bei
+  `jetstream_connected: true`, kommt nichts an.
+* `lag_ms` — Differenz zwischen lokaler Uhr und `time_us` des letzten Events,
+  auf `0` geklemmt, wenn negativ. `0` heißt also auch „noch kein Event gesehen".
+
+### Logs
+
+Beide Binaries loggen über `tracing_subscriber::fmt()` mit
+`EnvFilter::try_from_default_env()` auf stdout/stderr, Fallback-Filter `info`.
+Unter systemd landet alles im Journal:
+
+```bash
+journalctl -u maarcadetweet-pds -f
+journalctl -u maarcadetweet-appview -f
+```
+
+Empfehlung für den Betrieb (aus `.env.example` abgeleitet, `sqlx` sonst sehr
+gesprächig):
+
+```
+RUST_LOG=info,sqlx=warn
+```
+
+Log-Zeilen, auf die es sich lohnt zu achten:
+
+| Meldung | Bedeutung |
+|---|---|
+| `jetstream error: …` / `reconnecting in Ns` | Firehose-Verbindung verloren |
+| `apply_commit failed; NOT advancing cursor` | Indexer-Fehler, Event wird beim nächsten Replay erneut versucht |
+| `cursor flush failed` | Cursor-Schreibvorgang auf die DB schlug fehl |
+| `s3 ping failed at startup` | MinIO beim PDS-Start nicht erreichbar |
+| `plc submit failed (dev ok)` | PLC-Directory nicht erreichbar; die DID bleibt lokal gültig, ist aber global nicht registriert |
+
+## 9. Neustart-Verhalten
+
+**PDS.** Zustandslos bis auf Postgres und MinIO. Der In-Memory-Blockstore
+(`MemoryBlockstore` in `state.rs`) wird beim Start neu aufgebaut; persistent
+sind `repo_blocks`, `repos`, `users`, `blobs`, `sessions`, `plc_ops` in der
+PDS-DB. Migrationen laufen bei jedem Start (idempotent über
+`_sqlx_migrations`).
+
+**AppView — Jetstream-Cursor.** Der Fortschritt liegt in der Tabelle
+`jetstream_cursor` (genau eine Zeile, `id = 1`, Spalte `cursor` =
+Mikrosekunden seit Epoch). Der Ablauf:
+
+1. Beim Start liest `indexer::cursor_get` die Zeile. Ist der Wert `> 0`, wird
+   der Consumer mit `with_cursor(...)` gebaut und schickt `cursor` im
+   `subscribe`-Options-Frame an Jetstream — die Verbindung setzt dort fort
+   statt am Live-Ende. Bei `0` startet er ohne Cursor.
+2. Der Handler zählt jedes Event. Nur jedes 100. Event schickt er einen Tick
+   in einen `mpsc`-Kanal (Kapazität 32, `try_send` — bei vollem Kanal wird der
+   Tick verworfen).
+3. Ein Hintergrund-Task sammelt die Ticks und schreibt alle 500 ms das Maximum
+   per `UPDATE jetstream_cursor SET cursor = GREATEST(cursor, $1)`. Der Cursor
+   kann dadurch nie zurückspringen.
+4. Schlägt `apply_commit` fehl, wird der Cursor für dieses Event **nicht**
+   vorgerückt — der Reconnect liefert es erneut.
+
+Praktische Folge: Nach einem Neustart werden bis zu ~100 Events (plus die
+letzten 500 ms) erneut verarbeitet. Alle Indexer-Schreibpfade sind als Upserts
+gebaut, das Replay ist also unschädlich. Umgekehrt gilt: War die AppView länger
+weg als Jetstreams Backfill-Fenster, sind die Events dazwischen verloren; ein
+Backfill-Werkzeug dafür existiert nicht (noch offen).
+
+**Eigene Posts sind vom Cursor unabhängig.** Die PDS pusht jeden lokalen Commit
+direkt an `POST /internal/ingest-commit`. Der Push ist best effort mit 5 s
+Timeout und blockiert den Record-Write nie — fällt er aus, kommt der Record
+später über Jetstream (sofern die Collection in `JETSTREAM_COLLECTIONS` steht,
+siehe Abschnitt 3).
+
+**Handle-Sync.** Läuft als eigener Task alle
+`APPVIEW_HANDLE_SYNC_INTERVAL_SECS` Sekunden und füllt leere `posts.handle`
+nach — zuerst über die lokale PDS (`PdsHandleResolver`, 2 s Timeout), dann PLC
+bzw. `did:web`. Nach einem Neustart holt der erste Durchlauf das nach; der
+Zustand ist reine Anzeigekosmetik.
+
+## 10. Was noch offen ist
+
+* Kein Compose-Service für `pds-server` / `appview` — das Compose-File deckt nur
+  Postgres und MinIO ab. Es gibt kein Dockerfile im Repo.
+* `at-blob` spricht ausschließlich MinIO ohne Signature V4 (siehe Modul-Doku in
+  `crates/at-blob/src/s3.rs`); echtes AWS S3 funktioniert damit nicht.
+* Kein Graceful-Shutdown, keine Readiness- (im Unterschied zur Liveness-)Probe.
+* `aud` wird beim Token-Check nicht validiert (`verify_jwt` setzt
+  `validate_aud = false`), obwohl die PDS `did:web:appview.maarcadetweet.local`
+  einsetzt. Signatur, Ablauf, `scope` und `sub` werden geprüft.
+* Notifications werden nie gelöscht; ein Unlike/Unfollow lässt die Zeile stehen.
+* Kein Backfill-Werkzeug für Jetstream-Lücken.

docs/tauri-release.md

@@ -0,0 +1,311 @@
+# Tauri-Release und Auto-Update
+
+Der Desktop-Client ist auf Auto-Update vorbereitet, aber nicht scharf
+geschaltet. Dieses Dokument beschreibt den vollständigen Weg von den
+Signing-Keys bis zum ausgelieferten `latest.json` — und was dafür im Repo noch
+fehlt.
+
+Alle Pfade sind relativ zu `crates/tauri-app/`, sofern nicht anders angegeben.
+
+## Ist-Zustand
+
+| Baustein | Stand |
+|---|---|
+| Rust-Plugin | `tauri_plugin_updater::Builder::new().build()` ist in `src-tauri/src/lib.rs` registriert |
+| Capability | `src-tauri/capabilities/default.json` enthält `updater:default` → `allow-check`, `allow-download`, `allow-install`, `allow-download-and-install` für das `main`-Window |
+| Config | `src-tauri/tauri.conf.json`, Block `plugins.updater`: leerer `pubkey`, Platzhalter-Endpoint `https://releases.maarcadetweet.local/{{target}}/{{arch}}/{{current_version}}` |
+| Updater-Artefakte | `bundle.createUpdaterArtifacts` ist **nicht** gesetzt (Default: aus) — der Build erzeugt keine `.sig`-Dateien und kein `.app.tar.gz` |
+| Aufruf im Client | **Fehlt.** Weder das npm-Paket `@tauri-apps/plugin-updater` noch ein `check()`-Aufruf existieren (weder in `src/` noch in `src-tauri/src/`) |
+| CLI | `@tauri-apps/cli` ist als devDependency installiert, lokal geprüft: `npx tauri --version` → `tauri-cli 2.11.4` |
+| Plugin-Version | `tauri-plugin-updater` 2.10.1 laut `src-tauri/Cargo.lock` |
+
+**Wichtig:** Die Felder `active` und `dialog` in `plugins.updater` stammen aus
+Tauri v1. Der v2-Updater kennt sie nicht — seine `Config` besteht aus
+`endpoints`, `pubkey`, `windows`, `dangerousInsecureTransportProtocol`,
+`dangerousAcceptInvalidCerts`, `dangerousAcceptInvalidHostnames`. Unbekannte
+Schlüssel werden beim Deserialisieren still ignoriert. `"active": false`
+schaltet den Updater also **nicht** ab; dass heute nichts passiert, liegt
+allein daran, dass niemand `check()` aufruft. Wer den Updater wirklich
+deaktivieren will, entfernt den `plugins.updater`-Block und die
+`tauri_plugin_updater`-Registrierung.
+
+## 1. Signing-Keys erzeugen
+
+Der Updater akzeptiert nur signierte Artefakte. Das Schlüsselpaar wird einmal
+erzeugt und danach nie wieder gewechselt — ein neuer Public Key macht alle
+installierten Clients update-unfähig.
+
+```bash
+cd crates/tauri-app
+npx tauri signer generate -w ~/.tauri/maarcadetweet.key
+```
+
+Optionen laut `npx tauri signer generate --help`:
+
+| Flag | Bedeutung |
+|---|---|
+| `-w, --write-keys <PFAD>` | Privaten Schlüssel in eine Datei schreiben (sonst nur stdout) |
+| `-p, --password <PW>` | Passwort für den privaten Schlüssel setzen |
+| `-f, --force` | Vorhandene Datei überschreiben |
+| `--ci` | Keine interaktiven Rückfragen |
+
+Ergebnis: `~/.tauri/maarcadetweet.key` (privat, **niemals** ins Repo) und
+`~/.tauri/maarcadetweet.key.pub` (öffentlich, base64). Der Inhalt der
+`.pub`-Datei ist genau das, was in `pubkey` gehört.
+
+Für den Build-Rechner bzw. die CI:
+
+```bash
+export TAURI_SIGNING_PRIVATE_KEY="$(cat ~/.tauri/maarcadetweet.key)"
+export TAURI_SIGNING_PRIVATE_KEY_PASSWORD="…"
+```
+
+`TAURI_SIGNING_PRIVATE_KEY` akzeptiert den Schlüsselinhalt oder einen Pfad.
+Fehlt die Variable beim Build mit aktivierten Updater-Artefakten, bricht das
+Bundling ab.
+
+## 2. Konfiguration — ohne den Dev-Zustand zu brechen
+
+Die laufende `src-tauri/tauri.conf.json` soll unangetastet bleiben (leerer
+`pubkey`, keine Updater-Artefakte). Die CLI kann Konfigurationen zur Build-Zeit
+zusammenführen:
+
+```
+-c, --config <CONFIG>   JSON strings or paths to JSON, JSON5 or TOML files to
+                        merge with the default configuration file
+```
+
+Der saubere Weg ist deshalb eine **Release-Overlay-Datei**, die nur die
+Release-Unterschiede enthält. Anlegen als
+`crates/tauri-app/src-tauri/tauri.release.conf.json` (existiert noch nicht):
+
+```json
+{
+  "bundle": {
+    "createUpdaterArtifacts": true
+  },
+  "plugins": {
+    "updater": {
+      "endpoints": [
+        "https://releases.example.org/maarcadetweet/latest.json"
+      ],
+      "pubkey": "dW50cnVzdGVkIGNvbW1lbnQ6…HIER_DER_INHALT_VON_.key.pub…",
+      "windows": {
+        "installMode": "passive"
+      }
+    }
+  }
+}
+```
+
+Build damit:
+
+```bash
+cd crates/tauri-app
+npx tauri build --config src-tauri/tauri.release.conf.json
+```
+
+Feldbedeutungen (geprüft an `tauri-plugin-updater` 2.11 / `tauri-utils` 2.9):
+
+| Feld | Bedeutung |
+|---|---|
+| `bundle.createUpdaterArtifacts` | `true` erzeugt die Updater-Artefakte (`.sig`, unter macOS zusätzlich das `.app.tar.gz`). Alternativ `"v1Compatible"` für v1-Clients |
+| `plugins.updater.pubkey` | Public Key aus Schritt 1. Pflichtfeld — fehlt es ganz, scheitert das Deserialisieren der Plugin-Config |
+| `plugins.updater.endpoints` | Liste von URLs, der Reihe nach probiert. Müssen `https` sein: in Release-Builds bricht ein `http`-Endpoint mit `InsecureTransportProtocol` ab (im Debug-Build nur eine Warnung), es sei denn `dangerousInsecureTransportProtocol` ist gesetzt |
+| `plugins.updater.windows.installMode` | `passive` (Default), `basicUi` oder `quiet` |
+
+### Endpoint-Platzhalter
+
+In der Endpoint-URL werden ersetzt: `{{current_version}}`, `{{target}}`,
+`{{arch}}` und `{{bundle_type}}`. Achtung auf einen Fallstrick — der bereits in
+der Config stehende Platzhalter-Endpoint benutzt genau diese Form:
+
+* `{{target}}` wird in der **URL** nur durch das Betriebssystem ersetzt
+  (`linux`, `darwin`, `windows`) — nicht durch `darwin-aarch64`.
+* `{{arch}}` liefert die Architektur (`x86_64`, `aarch64`, `i686`, `armv7`,
+  `riscv64`).
+* `{{bundle_type}}` liefert den laufenden Bundle-Typ: `app`, `msi`, `nsis`,
+  `appimage`, `deb` oder `rpm` — bzw. `unknown`, wenn er nicht bestimmbar ist.
+
+Ein statisches `latest.json` (eine Datei für alle Plattformen) ist der
+einfachere Weg und kommt ohne Platzhalter aus.
+
+## 3. `latest.json`
+
+Der Updater versteht zwei Formate. Für einen einfachen Static-File-Server ist
+das **statische Format** richtig:
+
+```json
+{
+  "version": "0.2.0",
+  "notes": "Thread-Ansicht, schnellere Timeline",
+  "pub_date": "2026-01-15T10:00:00Z",
+  "platforms": {
+    "darwin-aarch64": {
+      "signature": "<Inhalt von maarcadetweet.app.tar.gz.sig>",
+      "url": "https://releases.example.org/maarcadetweet/0.2.0/maarcadetweet_aarch64.app.tar.gz"
+    },
+    "darwin-x86_64": {
+      "signature": "…",
+      "url": "https://releases.example.org/maarcadetweet/0.2.0/maarcadetweet_x64.app.tar.gz"
+    },
+    "linux-x86_64": {
+      "signature": "…",
+      "url": "https://releases.example.org/maarcadetweet/0.2.0/maarcadetweet_0.2.0_amd64.AppImage"
+    },
+    "windows-x86_64": {
+      "signature": "…",
+      "url": "https://releases.example.org/maarcadetweet/0.2.0/maarcadetweet_0.2.0_x64-setup.exe"
+    }
+  }
+}
+```
+
+Regeln, die der Plugin-Code vorgibt:
+
+* **Schlüssel der `platforms`-Map:** Der Updater sucht in dieser Reihenfolge
+  nach `{os}-{arch}-{installer}` und danach nach `{os}-{arch}`.
+  `os` ∈ `linux` | `darwin` | `windows`, `arch` ∈ `i686` | `x86_64` | `armv7` |
+  `aarch64` | `riscv64`, `installer` ∈ `appimage` | `deb` | `rpm` | `app` |
+  `msi` | `nsis`. Die Kurzform `darwin-aarch64` reicht also; die lange Form
+  `windows-x86_64-nsis` ist nur nötig, wenn man MSI und NSIS gleichzeitig
+  ausliefert.
+* **`version`** wird als Semver geparst. Ein Update wird nur angeboten, wenn
+  `release.version > current_version` — die Version kommt aus dem Feld
+  `version` in `tauri.conf.json` (heute `0.1.0`). Ein Release ohne
+  Versionsbump wird stillschweigend ignoriert.
+* **`signature`** ist der **Inhalt** der zugehörigen `.sig`-Datei, nicht deren
+  URL.
+* **`notes`** und **`pub_date`** sind optional; `pub_date` als RFC 3339.
+* Ein dynamischer Endpoint darf mit **`204 No Content`** antworten, wenn es
+  kein Update gibt. Dann liefert er statt der `platforms`-Map ein flaches
+  Objekt mit `version`, `url` und `signature` für genau die anfragende
+  Plattform.
+
+## 4. Build pro Plattform
+
+`tauri build` ist ein Cross-Build nur eingeschränkt — jede Plattform wird auf
+ihrem eigenen Host (oder Runner) gebaut.
+
+```bash
+cd crates/tauri-app
+
+# macOS (Apple Silicon)
+npx tauri build --config src-tauri/tauri.release.conf.json
+
+# macOS Universal (beide Rust-Targets müssen installiert sein)
+npx tauri build --target universal-apple-darwin \
+                --config src-tauri/tauri.release.conf.json
+
+# Windows / Linux jeweils auf dem passenden Host, gleicher Aufruf
+```
+
+Ablauf laut `build.beforeBuildCommand` in `tauri.conf.json`: erst
+`npm run build` (Vite → `crates/tauri-app/dist`, entspricht `frontendDist:
+"../dist"`), dann der Cargo-Release-Build, dann das Bundling.
+`bundle.targets` steht auf `"all"`.
+
+Nützliche Flags (aus `npx tauri build --help`):
+
+| Flag | Zweck |
+|---|---|
+| `-t, --target <TRIPLE>` | Ziel-Triple, oder `universal-apple-darwin` |
+| `-b, --bundles <LISTE>` | Nur bestimmte Bundle-Typen erzeugen |
+| `--no-bundle` | Nur das Binary, kein Installer |
+| `-c, --config <PFAD>` | Config-Overlay (siehe oben) |
+| `--ci` | Keine interaktiven Rückfragen |
+
+## 5. Wo die Artefakte landen
+
+`crates/tauri-app/src-tauri/Cargo.toml` deklariert ein eigenes `[workspace]`,
+der Build-Output liegt deshalb **nicht** im Repo-Root-`target/`, sondern unter
+`crates/tauri-app/src-tauri/target/release/bundle/`. Mit `--target <triple>`
+schiebt sich das Triple dazwischen:
+`src-tauri/target/<triple>/release/bundle/`.
+
+| Plattform | Pfad unter `bundle/` | Für den Updater relevant |
+|---|---|---|
+| macOS | `macos/maarcadetweet.app` | `macos/maarcadetweet.app.tar.gz` + `.tar.gz.sig` |
+| macOS | `dmg/maarcadetweet_<version>_<arch>.dmg` | nein (nur für die Erstinstallation) |
+| Windows | `msi/maarcadetweet_<version>_<arch>_<lang>.msi` | `.msi` + `.msi.sig` |
+| Windows | `nsis/maarcadetweet_<version>_<arch>-setup.exe` | `.exe` + `.exe.sig` |
+| Linux | `appimage/maarcadetweet_<version>_<arch>.AppImage` | `.AppImage` + `.AppImage.sig` |
+| Linux | `deb/…deb`, `rpm/…rpm` | nein |
+
+Die `.sig`-Dateien entstehen nur, wenn `createUpdaterArtifacts` aktiv ist und
+die Signing-Env-Variablen gesetzt sind. Für das `latest.json` wird der
+**Dateiinhalt** der `.sig` gebraucht, das Artefakt selbst wird nicht
+ausgeliefert.
+
+## 6. Was im Client noch fehlt
+
+Config und Signaturen allein bewirken nichts — der Client fragt nirgends nach
+Updates. Es gibt zwei Wege:
+
+### a) Vom Frontend aus
+
+```bash
+cd crates/tauri-app
+npm install @tauri-apps/plugin-updater @tauri-apps/plugin-process
+```
+
+```ts
+import { check } from "@tauri-apps/plugin-updater";
+import { relaunch } from "@tauri-apps/plugin-process";
+
+const update = await check();
+if (update) {
+  await update.downloadAndInstall();
+  await relaunch();
+}
+```
+
+Die Capability erlaubt `check`, `download`, `install` und
+`downloadAndInstall` bereits. **Zusätzlich nötig:** `tauri-plugin-process` als
+Rust-Dependency, `tauri_plugin_process::init()` in `lib.rs` und
+`"process:default"` in `capabilities/default.json` — sonst schlägt `relaunch()`
+fehl.
+
+### b) Vom Rust-Layer aus
+
+```rust
+use tauri_plugin_updater::UpdaterExt;
+
+if let Ok(Some(update)) = app.updater()?.check().await {
+    update.download_and_install(|_, _| {}, || {}).await?;
+}
+```
+
+Ohne npm-Abhängigkeit, dafür ohne UI-Kontrolle im Frontend. Der Aufruf gehört
+in den `setup`-Hook oder hinter ein Tauri-Command, das die Svelte-Seite
+aufrufen kann.
+
+Welcher Weg genommen wird, ist **noch offen** — im Repo existiert keiner von
+beiden.
+
+## 7. Release-Checkliste
+
+1. `version` in `src-tauri/tauri.conf.json` erhöhen (Semver; der Vergleich
+   entscheidet, ob ein Update angeboten wird). `package.json` und
+   `src-tauri/Cargo.toml` der Konsistenz halber mitziehen.
+2. Auf jedem Plattform-Host mit gesetzten `TAURI_SIGNING_PRIVATE_KEY*`-Variablen
+   und dem Release-Overlay bauen.
+3. Installer und Updater-Artefakte einsammeln, `.sig`-Inhalte auslesen.
+4. `latest.json` schreiben und zusammen mit den Artefakten unter einer
+   `https`-URL veröffentlichen. Die URL muss zum `endpoints`-Eintrag passen.
+5. Mit einer älteren installierten Version gegenprüfen, dass `check()` das
+   Update findet und die Signaturprüfung durchgeht.
+
+## 8. Offene Punkte
+
+* Kein Release-Overlay im Repo — die Datei aus Abschnitt 2 muss angelegt
+  werden. Der Endpoint `https://releases.maarcadetweet.local/…` in der aktuellen
+  Config ist ein Platzhalter und existiert nicht.
+* Kein Update-Server, kein CI-Workflow, kein Skript, das `latest.json` erzeugt
+  (`scripts/` ist leer).
+* Keine Code-Signierung/Notarisierung für macOS und keine Authenticode-Signatur
+  für Windows konfiguriert (`bundle` enthält weder `macOS.signingIdentity` noch
+  `windows.certificateThumbprint`). Der Tauri-Updater-Schlüssel ersetzt das
+  nicht — ohne Notarisierung meldet Gatekeeper die App als nicht verifiziert.
+* Die Felder `active` und `dialog` in `plugins.updater` sind v1-Reste ohne
+  Wirkung (siehe oben) und sollten beim Scharfschalten entfernt werden.

migrations/appview/0008_notifications.sql

@@ -0,0 +1,113 @@
+-- AppView database schema 0008: notifications + follow-list pagination.
+--
+-- Why
+--
+-- Phase 5 shipped the read API (timeline / profile / search / post) but
+-- the client had no way to learn that *someone else* interacted with
+-- the user: a like, a repost, a follow or a reply never produced a
+-- durable record. The Tauri client's tray/notification path (Phase 7)
+-- therefore had nothing to poll. This migration adds the table the
+-- Jetstream indexer writes into and the read API serves from.
+--
+-- Table shape
+--   id             BIGSERIAL — monotonic tiebreaker for the keyset
+--                  cursor. The API's opaque cursor is
+--                  `(indexed_at, id)`, mirroring the
+--                  `(indexed_at, uri)` pair used by /api/timeline/home,
+--                  so the same `routes::cursor` encoder is reused.
+--   recipient_did  the user who should SEE the notification (the post
+--                  author for like/repost/reply, the followed user for
+--                  follow).
+--   author_did     the user who CAUSED it (the liker / reposter /
+--                  follower / replier).
+--   kind           'like' | 'repost' | 'follow' | 'reply'. Enforced by
+--                  a CHECK rather than a Postgres ENUM so adding a
+--                  variant later is an ALTER ... DROP/ADD CONSTRAINT
+--                  instead of a type migration that locks every
+--                  dependent object.
+--   subject_uri    the post the notification is *about*. NULL for
+--                  'follow' (there is no post). For 'like'/'repost'
+--                  it's the liked/reposted post (the recipient's own
+--                  post); for 'reply' it's the REPLY itself, because
+--                  the interesting text to show in the notification
+--                  list is what the replier wrote, not what the
+--                  recipient already knows they posted.
+--   created_at     the interaction's own `createdAt` from the AT record.
+--   indexed_at     when WE saw it. This is what the list is ordered by,
+--                  for the same reason the timeline orders by
+--                  `posts.indexed_at`: a client-supplied `created_at`
+--                  can be arbitrarily far in the past or future and
+--                  would break keyset pagination.
+--   read_at        NULL = unread. Set in bulk by
+--                  `POST /api/notifications/seen`.
+--
+-- Deliberately NO `CHECK (recipient_did <> author_did)`
+-- ------------------------------------------------------
+-- Self-interactions must not produce notifications, and the indexer
+-- enforces that in two places (a pure `should_notify` guard in Rust
+-- plus a `WHERE $1 <> $2` in the INSERT ... SELECT). A CHECK would
+-- turn a future slip into a constraint violation that aborts the
+-- surrounding like/repost transaction — i.e. it would lose the *like*
+-- because of a notification bug. Filtering is strictly better than
+-- failing here.
+--
+-- Idempotency
+-- -----------
+-- `notifications_dedupe_idx` is the unique constraint the indexer's
+-- `ON CONFLICT ... DO NOTHING` infers. `subject_uri` is nullable and
+-- NULLs never collide in a plain unique index, so the index is on
+-- `COALESCE(subject_uri, '')` — that makes the two follow rows
+-- (subject_uri IS NULL) for the same (recipient, author) pair collide
+-- as intended.
+--
+-- Consequence worth knowing: unlike-then-relike (or unfollow-then-
+-- refollow) does NOT produce a second notification, because the tuple
+-- is identical. That is the desired behaviour — it makes notification
+-- spam via toggling impossible — but it does mean a notification is
+-- "once per (recipient, author, kind, subject)" for all time.
+
+CREATE TABLE notifications (
+    id             BIGSERIAL PRIMARY KEY,
+    recipient_did  TEXT NOT NULL,
+    author_did     TEXT NOT NULL,
+    kind           TEXT NOT NULL
+                     CHECK (kind IN ('like', 'repost', 'follow', 'reply')),
+    subject_uri    TEXT,
+    created_at     TIMESTAMPTZ NOT NULL,
+    indexed_at     TIMESTAMPTZ NOT NULL DEFAULT now(),
+    read_at        TIMESTAMPTZ
+);
+
+-- Primary read path: `WHERE recipient_did = $1 ORDER BY indexed_at DESC,
+-- id DESC`. The trailing `id DESC` makes the index cover the keyset
+-- predicate `(indexed_at, id) < ($2, $3)` end-to-end, so a page fetch
+-- never sorts.
+CREATE INDEX notifications_recipient_indexed_at_idx
+    ON notifications (recipient_did, indexed_at DESC, id DESC);
+
+-- Dedupe / ON CONFLICT target. See the "Idempotency" note above.
+CREATE UNIQUE INDEX notifications_dedupe_idx
+    ON notifications (recipient_did, author_did, kind, COALESCE(subject_uri, ''));
+
+-- `GET /api/notifications/count` is a hot poll from the client's tray
+-- badge, so the unread slice gets its own partial index. It stays tiny
+-- because rows leave it as soon as they're marked seen.
+CREATE INDEX notifications_unread_idx
+    ON notifications (recipient_did)
+    WHERE read_at IS NULL;
+
+-- =====================================================
+-- follows: pagination indexes for the follower/following lists
+-- =====================================================
+--
+-- `GET /api/followers` and `GET /api/following` page with the same
+-- keyset scheme as the timeline: `(indexed_at, <other side's did>)`.
+-- The pre-existing indexes cover only the equality half (the PK covers
+-- `follower_did`, `follows_subject_idx` covers `subject_did`), which
+-- leaves Postgres sorting the whole follower set on every page. These
+-- two make both directions index-ordered.
+CREATE INDEX IF NOT EXISTS follows_subject_indexed_at_idx
+    ON follows (subject_did, indexed_at DESC, follower_did DESC);
+
+CREATE INDEX IF NOT EXISTS follows_follower_indexed_at_idx
+    ON follows (follower_did, indexed_at DESC, subject_did DESC);

migrations/appview/0009_handle_lookup_indexes.sql

@@ -0,0 +1,58 @@
+-- AppView database schema 0009: indexes for handle → DID lookups.
+--
+-- `/api/profile/<handle>` took 9.5 s on a 3.3 M-row `posts` table
+-- (measured against the dev instance). Both halves of `resolve_profile`
+-- were unindexed:
+--
+--   1. SELECT did FROM profiles WHERE LOWER(handle) = LOWER($1)
+--   2. SELECT did FROM posts    WHERE handle = $1
+--      ORDER BY indexed_at DESC LIMIT 1        -- the fallback
+--
+-- Step 2 was a parallel sequential scan over every post ever indexed
+-- (`Rows Removed by Filter: 1101310` per worker), and it runs on every
+-- profile view in the client.
+--
+-- On `profiles`: migration 0007 dropped exactly this index, reasoning
+-- that "every caller derives a DID first (via posts.handle or the
+-- handle-sync worker) and then queries profiles by PK". That stopped
+-- being true when `resolve_profile` learned to prefer the profiles
+-- cache — it now asks `profiles` by handle *first*, precisely the
+-- lookup 0007 removed the support for. Re-added, matching the
+-- expression in the query (`LOWER(handle)`) so the planner can use it.
+CREATE INDEX IF NOT EXISTS profiles_handle_lower_idx
+    ON profiles (LOWER(handle));
+
+-- On `posts`: `(handle, indexed_at DESC)` covers filter *and* sort, so
+-- the LIMIT 1 becomes an index scan that stops at the first row.
+--
+-- Partial on `handle <> ''`: empty handles are the un-backfilled
+-- majority on a firehose-fed instance and are never looked up by this
+-- path (the handle-sync worker queries them through its own predicate),
+-- so excluding them keeps the index small on the largest table we have.
+CREATE INDEX IF NOT EXISTS posts_handle_indexed_at_idx
+    ON posts (handle, indexed_at DESC)
+    WHERE handle <> '';
+
+-- =====================================================
+-- posts: the cold-start global feed
+-- =====================================================
+--
+-- `/api/timeline/home` falls back to the global recent feed for users
+-- without a follow graph — every new account's first screen. It took
+-- 7.4 s (parallel seq scan + top-N sort over 3.3 M rows) and timed out
+-- the integration tests' 5 s client.
+--
+-- `posts_collection_indexed_at_uri_idx (collection, indexed_at DESC,
+-- uri DESC)` cannot serve it: the query filters
+-- `collection IN ('app.twi.post','app.bsky.feed.post')`, and with two
+-- leading values the index no longer yields rows in `indexed_at` order,
+-- so the planner falls back to scanning and sorting.
+--
+-- A partial index over exactly that predicate moves the collection
+-- filter into the index definition, which leaves `(indexed_at DESC,
+-- uri DESC)` as the sort key — the LIMIT then stops after the first
+-- page. Same shape as the existing `posts_did_indexed_at_uri_idx`,
+-- which is partial on the same two collections.
+CREATE INDEX IF NOT EXISTS posts_feed_indexed_at_uri_idx
+    ON posts (indexed_at DESC, uri DESC)
+    WHERE collection IN ('app.twi.post', 'app.bsky.feed.post');