Merge pull request #389 from Coffey-Labs/fix/push-subscriptions

Stop duplicate push notifications and piling up subscriptions
Merge main into fix/push-subscriptions
2026-09-16 11:41:37 -07:00 · 2026-09-16 11:39:35 -07:00 · 2026-09-16 11:38:22 -07:00 · 2026-09-16 11:36:07 -07:00 · 2026-09-16 11:27:47 -07:00 · 2026-09-16 11:02:42 -07:00
223 changed files with 4911 additions and 2191 deletions
@@ -3,4 +3,7 @@ node_modules
 **/dist
 .git
 .env
+# deploy.example.sh keeps its settings in .env.production; any .env.* holds APP_SECRET.
+.env.*
+!.env.example
 server/data
@@ -0,0 +1,43 @@
+<!--
+  Thanks for contributing to ihasmail. CONTRIBUTING.md has the full guide;
+  this is the short version. Delete any section that does not apply.
+-->
+
+## Summary
+
+<!-- What changes, and why. -->
+
+## Related issues
+
+<!-- e.g. Closes #123. Leave blank if there are none. -->
+
+## Translations
+
+<!--
+  Nine languages ship alongside English, and a missing key silently renders
+  its English source -- so an untranslated string is invisible until somebody
+  reading that language finds it. Say which this PR is, explicitly:
+
+  - Adds or alters user-visible strings: how many keys, and the fallback
+    count before and after.
+  - Adds none.
+
+  "Adds none" is an answer. Saying nothing is not -- it leaves it to be
+  inferred. See CONTRIBUTING.md -> Translations.
+-->
+
+## Testing
+
+<!--
+  What you ran, and what you saw. `npm run typecheck`, `npm test` and
+  `npm run build` all run in CI, so the useful thing here is what CI cannot
+  do: which flows you exercised by hand, and against what -- a real Stalwart
+  instance, or `npm run dev:mock`.
+
+  If the change is visible on screen, drive the built app, not just the
+  store. See CONTRIBUTING.md -> Verifying UI work.
+-->
+
+## Screenshots
+
+<!-- For UI changes. Before/after, or a GIF for anything with motion. -->
@@ -15,8 +15,19 @@ jobs:
  build:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v7
-      - uses: actions/setup-node@v7
+      # Every `uses:` in this repository is pinned to a full commit SHA, with
+      # the release it belongs to in the trailing comment, and the repository
+      # requires it -- an unpinned ref fails the run rather than quietly
+      # resolving. A tag is a mutable pointer: `@v7` is whatever the publisher
+      # last moved it to, so trusting one is trusting every future version of
+      # that action, including the one pushed by whoever compromises the
+      # account. Read the comment for the version; the SHA is what runs.
+      #
+      # Dependabot updates both halves together on its weekly github-actions
+      # run, so this costs nothing to keep current -- do not "simplify" a pin
+      # back to a tag.
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
        with:
          node-version: 26
          cache: npm
@@ -39,11 +39,12 @@ jobs:
    permissions:
      packages: write
    steps:
-      # Pinned to a commit rather than a moving major tag. This action is
-      # handed `packages: write` and its whole job is deletion, so a tag
-      # repointed at something else -- by a compromise or a mistake upstream --
-      # is a bad day. v1.2.2.
-      - uses: dataaxiom/ghcr-cleanup-action@d52806a0dc70b430571a37da1fde39733ffd640f
+      # The only third-party action here that is not published by GitHub or
+      # Docker, and the one with the most to lose: it is handed
+      # `packages: write` and its whole job is deletion, so a ref repointed at
+      # something else -- by a compromise or a mistake upstream -- is a bad
+      # day. It was pinned to a commit long before the rest of them were.
+      - uses: dataaxiom/ghcr-cleanup-action@d52806a0dc70b430571a37da1fde39733ffd640f # v1.2.2
        with:
          owner: Coffey-Labs
          package: ihasmail
@@ -76,11 +76,11 @@ jobs:
      version: ${{ steps.v.outputs.version }}
      docker_tag: ${{ steps.v.outputs.docker_tag }}
    steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          ref: ${{ inputs.ref || github.ref }}
          fetch-depth: 0
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
        with:
          node-version: 26
      - id: v
@@ -108,18 +108,18 @@ jobs:
          - platform: linux/arm64
            runner: ubuntu-24.04-arm
    steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          ref: ${{ inputs.ref || github.ref }}
-      - uses: docker/setup-buildx-action@v4
-      - uses: docker/login-action@v4
+      - uses: docker/setup-buildx-action@594f3bf4285d9ea8dc53c9a0c9c4092420091003 # v4.4.0
+      - uses: docker/login-action@dbcb813823bdd20940b903addbd779551569679f # v4.6.0
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - name: Build and push by digest
        id: push
-        uses: docker/build-push-action@v7
+        uses: docker/build-push-action@c3c9e263c25d99ce0380d002d59b67737d91b0dc # v7.4.0
        with:
          context: .
          platforms: ${{ matrix.platform }}
@@ -140,7 +140,7 @@ jobs:
          # `image@sha256:sha256:...` when the reference is rebuilt.
          digest="${{ steps.push.outputs.digest }}"
          touch "/tmp/digests/${digest#sha256:}"
-      - uses: actions/upload-artifact@v7
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
        with:
          # One artifact per platform; the merge job globs them back together.
          name: digest-${{ strategy.job-index }}
@@ -157,13 +157,13 @@ jobs:
      contents: read
      packages: write
    steps:
-      - uses: actions/download-artifact@v8
+      - uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
        with:
          path: /tmp/digests
          pattern: digest-*
          merge-multiple: true
-      - uses: docker/setup-buildx-action@v4
-      - uses: docker/login-action@v4
+      - uses: docker/setup-buildx-action@594f3bf4285d9ea8dc53c9a0c9c4092420091003 # v4.4.0
+      - uses: docker/login-action@dbcb813823bdd20940b903addbd779551569679f # v4.6.0
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
@@ -54,11 +54,11 @@ jobs:
      previous: ${{ steps.decide.outputs.previous }}
      count: ${{ steps.decide.outputs.count }}
    steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          ref: main
          fetch-depth: 0
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
        with:
          node-version: 26
      - id: decide
@@ -130,7 +130,7 @@ jobs:
    permissions:
      contents: write
    steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          ref: main
          fetch-depth: 0
@@ -1,6 +1,9 @@
 node_modules/
 dist/
 .env
+# deploy.example.sh keeps its settings in .env.production; any .env.* holds APP_SECRET.
+.env.*
+!.env.example
 *.log
 .DS_Store
 server/data/
@@ -58,6 +58,12 @@ check has passed — not afterwards — and the branch cannot be force-pushed or
 deleted. No approving review is required, so a PR of your own is not blocked
 waiting for one.

+**CI on a PR from a fork waits to be approved.** Every workflow run on an
+outside contributor's branch sits at *awaiting approval* until a maintainer
+starts it by hand, so the **build** check will not appear the moment you open
+the PR — that is the gate working, not a broken run. Pushing again will not
+start it, and neither will closing and reopening.
+
 ### Code Style

 - Match the existing formatting and naming conventions used elsewhere in the codebase.
@@ -48,6 +48,10 @@ works the same way — and dropped where 0.15 was the whole subject. Support for
 0.15 was removed on 2026-08-26; the last release that runs on it is tagged
 [`stalwart-0.15-support`](https://github.com/Coffey-Labs/ihasmail/releases/tag/stalwart-0.15-support).

+- **Push subscriptions are not replaced by a repeated `deviceClientId`, and an account holds fifteen.** ihasmail registered a new subscription on every renewal believing the old one would be replaced, as the mock did. **Confirmed live (0.16.22, 2026-09-16)**: a second create with the same `deviceClientId` leaves both in place, the sixteenth create is refused with `overQuota`, "There are too many subscriptions, please delete some before adding a new one.", and `update` of `expires` is accepted. `PushSubscription/get` does not return `url` (nor `keys`), so a subscription can only be matched by its `deviceClientId`. A `types` of `[]` or `null` is stored as *every* type, not none. Read from the 0.16.22 source: `EmailDelivery` changes only on delivery, a delivery reaches a subscription with an `emailPush` filter as an EmailPush alone, and the payload carries `id` and `threadId` only when they are named in `properties`. Browsers now subscribe to `EmailDelivery` only, extend rather than re-create, clear their own duplicates and make room on `overQuota`; the server removes what its previous process registered. The mock follows all of it ([#375](https://github.com/Coffey-Labs/ihasmail/issues/375)).
+
+- **A contact photo has to be a `data:` URI; Stalwart refuses one given as a `blobId`.** RFC 9610 lets JMAP put a `blobId` in a JSContact `Media` object, and ihasmail uploaded the photo and saved it that way, which the mock accepted. Stalwart does not: **confirmed live (0.16.22, 2026-09-16)**, a `ContactCard/set` create with `media.*.blobId` fails with `invalidProperties` on `media`, "blobIds in media is not supported." The RFC 9553 `uri` form with a `data:image/jpeg;base64,…` value is accepted on create and on update, and `ContactCard/get` returns it unchanged; a 134 KB one was accepted. Photos are now saved inline, and the mock refuses a `blobId` the same way ([#376](https://github.com/Coffey-Labs/ihasmail/issues/376)).
+
 - **Administration was built from Stalwart's source, and the first live run found the one thing the source reading got wrong.** Accounts and Domains were written on 2026-09-13 against the 0.16.22 source and a mock reproducing it, deployed the same day, and exercised against the live server from an administrator's session. On that server the Accounts list did not load: `x:Account/query` answered **`unsupportedFilter - type`**. A registry filter is keyed by the property's name *as it appears on the object*, and the discriminator is `@type`, so `{"type": "User"}` names nothing the server knows and fails the whole query; `{"@type": "User"}` is accepted. The research that fed the build had listed the field as `type`, and the mock took it without complaint — which is how it shipped. Fixed in [#336](https://github.com/Coffey-Labs/ihasmail/pull/336), and the mock now refuses any filter name the real server does not index, answering the way Stalwart does. Everything else was **confirmed live (2026-09-13)**, mostly read-only, with the domain writes made on a throwaway domain created for the purpose and removed afterwards:

  - **Permissions** come from `GET /api/account` in camelCase (`sysAccountGet`); an administrator's list held 641 of them and none were kebab-case, whatever the documentation shows. The menu gates on these.
@@ -36,9 +36,9 @@ settings included, belongs to Stalwart, so the container is disposable.

 | | |
 | --- | --- |
-| **Inbox & conversation (dark)** ![Inbox, dark theme](docs/screenshots/inbox-dark.jpg) | **Inbox & conversation (light)** ![Inbox, light theme](docs/screenshots/inbox-light.jpg) |
-| **Composer** ![Composer](docs/screenshots/compose.jpg) | **Calendar** ![Calendar](docs/screenshots/calendar.jpg) |
-| **Contacts** ![Contacts](docs/screenshots/contacts.jpg) | **Sieve filter builder** ![Filters](docs/screenshots/filters.jpg) |
+| **Inbox & conversation (dark)** ![Inbox, dark theme](screenshots/inbox-dark.jpg) | **Inbox & conversation (light)** ![Inbox, light theme](screenshots/inbox-light.jpg) |
+| **Composer** ![Composer](screenshots/compose.jpg) | **Calendar** ![Calendar](screenshots/calendar.jpg) |
+| **Contacts** ![Contacts](screenshots/contacts.jpg) | **Sieve filter builder** ![Filters](screenshots/filters.jpg) |

 Taken against the built-in mock with sample data. More, including the phone
 layout, on [ihasmail.org](https://ihasmail.org/#screenshots).
@@ -9,8 +9,21 @@ services:
        BASE_PATH: ${BASE_PATH:-}
    image: ihasmail:2
    restart: unless-stopped
+    # Loopback only: ihasmail expects a TLS reverse proxy in front of it. On
+    # every interface the app is reachable over plain HTTP, passwords and all,
+    # and with TRUST_PROXY any machine on a private network can set its own
+    # X-Forwarded-For. A proxy running in Docker can reach the service by name
+    # on the compose network and needs no published port at all.
    ports:
-      - "8080:8080"
+      - "127.0.0.1:8080:8080"
+    # The app needs no privileges and writes only to /data and /tmp.
+    read_only: true
+    tmpfs:
+      - /tmp
+    cap_drop:
+      - ALL
+    security_opt:
+      - no-new-privileges:true
    environment:
      STALWART_URL: ${STALWART_URL:?set STALWART_URL in .env}
      APP_SECRET: ${APP_SECRET:?set APP_SECRET in .env (openssl rand -base64 48)}
@@ -0,0 +1,47 @@
+#!/usr/bin/env node
+/*
+ * Write a Brotli and a gzip copy beside every compressible file in a web build.
+ *
+ * The server used to gzip the bundle again on every request that asked for it,
+ * at a level chosen for speed. These are made once, at the level chosen for
+ * size, and `server/src/static.ts` hands one out when the browser accepts it.
+ * Brotli at 11 is about 15% smaller than gzip for this bundle, and too slow to
+ * do per request, which is why it was never offered.
+ *
+ *   node scripts/precompress.mjs web/dist
+ */
+import { readdirSync, readFileSync, statSync, writeFileSync } from "node:fs";
+import { join, extname } from "node:path";
+import { brotliCompressSync, constants, gzipSync } from "node:zlib";
+
+const COMPRESSIBLE = new Set([".js", ".mjs", ".css", ".html", ".svg", ".json", ".webmanifest", ".txt", ".wasm"]);
+// Below this, the encoding costs more than it saves.
+const MIN_BYTES = 1024;
+
+function* files(dir) {
+  for (const entry of readdirSync(dir, { withFileTypes: true })) {
+    const p = join(dir, entry.name);
+    if (entry.isDirectory()) yield* files(p);
+    else yield p;
+  }
+}
+
+const root = process.argv[2];
+if (!root) {
+  console.error("usage: precompress.mjs <dir>");
+  process.exit(2);
+}
+let count = 0;
+let before = 0;
+let after = 0;
+for (const p of files(root)) {
+  if (!COMPRESSIBLE.has(extname(p)) || statSync(p).size < MIN_BYTES) continue;
+  const data = readFileSync(p);
+  const br = brotliCompressSync(data, { params: { [constants.BROTLI_PARAM_QUALITY]: 11, [constants.BROTLI_PARAM_SIZE_HINT]: data.length } });
+  writeFileSync(`${p}.br`, br);
+  writeFileSync(`${p}.gz`, gzipSync(data, { level: 9 }));
+  count++;
+  before += data.length;
+  after += br.length;
+}
+console.log(`precompressed ${count} files: ${(before / 1024).toFixed(0)} KB -> ${(after / 1024).toFixed(0)} KB brotli`);
@@ -5,8 +5,8 @@
 * images already use rather than whatever a window happens to be.
 *
 *   npm run dev:mock                       # in another terminal
- *   node docs/screenshots.mjs docs/screenshots
- *   node docs/screenshots-light.mjs docs/screenshots
+ *   node scripts/screenshots.mjs screenshots
+ *   node scripts/screenshots-light.mjs screenshots
 *
 * Restart the mock before a run. The filters shot creates rules, so a second
 * run against the same mock shows them twice.
@@ -30,7 +30,7 @@
 *   flip --bg to #f6f8fa. The compositor simply does not repaint everything a
 *   CSS-variable change touches while metrics are overridden. Launching Chrome
 *   at --window-size and never calling setDeviceMetricsOverride renders it
- *   correctly, which is what docs/screenshots-light.mjs does.
+ *   correctly, which is what scripts/screenshots-light.mjs does.
 *
 * assertTheme() stays either way: without it this script wrote a dark
 * screenshot under a light caption and reported success, and that is how the
@@ -226,7 +226,7 @@ try {
  await evaluate(`(() => { const c = [...document.querySelectorAll('button')].find(b => /close|discard/i.test(b.getAttribute('aria-label')||'')); if (c) c.click(); })()`);
  await sleep(800);

-  // (inbox-light is captured by docs/screenshots-light.mjs -- see the header)
+  // (inbox-light is captured by scripts/screenshots-light.mjs -- see the header)


  // --- calendar ---
@@ -69,7 +69,7 @@ test("the registry reports an account with nothing set up yet", async () => {
 });

 test("app passwords are created, listed once with their secret, and revoked", async () => {
-  const created = await post("/api/account/app-passwords", { description: "Thunderbird" });
+  const created = await post("/api/account/app-passwords", { description: "Thunderbird", current: "demo-password" });
  assert.equal(created.status, 200);
  assert.match(created.body.secret, /^\$app\$/, "the server's generated secret is returned");
  assert.ok(created.body.id);
@@ -84,8 +84,83 @@ test("app passwords are created, listed once with their secret, and revoked", as
  assert.deepEqual((await call("/api/account/security")).body.appPasswords, []);
 });

+test("an app password needs the account password", async () => {
+  const missing = await post("/api/account/app-passwords", { description: "Stolen" });
+  assert.equal(missing.status, 400);
+  assert.equal(missing.body.error, "missing_fields");
+  const wrong = await post("/api/account/app-passwords", { description: "Stolen", current: "not-my-password" });
+  assert.equal(wrong.status, 403);
+  assert.equal(wrong.body.error, "invalid_credentials");
+  assert.deepEqual((await call("/api/account/security")).body.appPasswords, [], "nothing was created");
+});
+
+test("a checked session cannot mint one through the JMAP proxy instead", async () => {
+  // Signed in without "my own device", so the proxy reads every request.
+  const res = await call("/api/jmap", {
+    method: "POST",
+    body: JSON.stringify({ using: ["urn:ietf:params:jmap:core"], methodCalls: [["x:AppPassword/set", { create: { n: { description: "Stolen" } } }, "0"]] }),
+  });
+  assert.equal(res.status, 403);
+  assert.deepEqual((await call("/api/account/security")).body.appPasswords, []);
+});
+
+test("attachments are kept out of the disk cache of a device that is not the person's own", async () => {
+  const up = await app.request("/api/upload/a1", { method: "POST", headers: { "x-requested-with": "ihasmail", "content-type": "text/plain", cookie }, body: "hello" });
+  assert.equal(up.status, 200);
+  const { blobId } = (await up.json()) as { blobId: string };
+  const name = encodeURIComponent("Invoice_\u202Efdp.exe");
+  const res = await app.request(`/api/blob/a1/${blobId}/${name}?accept=text/plain`, { headers: { cookie } });
+  assert.equal(res.status, 200);
+  assert.equal(res.headers.get("cache-control"), "no-store");
+  assert.equal(res.headers.get("content-disposition"), "attachment; filename*=UTF-8''Invoice_fdp.exe", "no direction override in the saved name");
+  await res.arrayBuffer();
+});
+
+test("a download passes a byte range through, for viewers that read in pieces", async () => {
+  const up = await app.request("/api/upload/a1", { method: "POST", headers: { "x-requested-with": "ihasmail", "content-type": "text/plain", cookie }, body: "hello world" });
+  const { blobId } = (await up.json()) as { blobId: string };
+  const url = `/api/blob/a1/${blobId}/greeting.txt?accept=text/plain`;
+  const part = await app.request(url, { headers: { cookie, range: "bytes=0-4" } });
+  assert.equal(part.status, 206);
+  assert.equal(part.headers.get("content-range"), "bytes 0-4/11");
+  assert.equal(part.headers.get("accept-ranges"), "bytes");
+  assert.equal(await part.text(), "hello");
+  const whole = await app.request(url, { headers: { cookie } });
+  assert.equal(whole.status, 200);
+  assert.equal(await whole.text(), "hello world");
+  const beyond = await app.request(url, { headers: { cookie, range: "bytes=50-60" } });
+  assert.equal(beyond.status, 416);
+  // Anything that is not a plain byte range is not passed on.
+  const odd = await app.request(url, { headers: { cookie, range: "items=0-4" } });
+  assert.equal(odd.status, 200);
+  await odd.arrayBuffer();
+});
+
+test("upstream caches let go of sessions that have aged out", async () => {
+  const { sweepUpstreamCaches, upstreamCacheSizes } = await import("./upstream.js");
+  // Signed in above, so this session has an entry.
+  assert.ok(upstreamCacheSizes().sessions >= 1);
+  sweepUpstreamCaches(Date.now() + 60 * 60_000);
+  assert.deepEqual(upstreamCacheSizes(), { sessions: 0, info: 0 });
+});
+
+test("the mock refuses a contact photo given as a blob id, as Stalwart does", async () => {
+  const jmap = (methodCalls: unknown[]) => call("/api/jmap", { method: "POST", body: JSON.stringify({ using: ["urn:ietf:params:jmap:core", "urn:ietf:params:jmap:contacts"], methodCalls }) });
+  const card = (media: unknown) => ({ "@type": "Card", version: "1.0", kind: "individual", name: { full: "Probe" }, addressBookIds: { ab1: true }, media });
+  const res = await jmap([["ContactCard/set", { accountId: "a1", create: {
+    blob: card({ p: { "@type": "Media", kind: "photo", blobId: "b1", mediaType: "image/jpeg" } }),
+    inline: card({ p: { "@type": "Media", kind: "photo", uri: "data:image/jpeg;base64,AA", mediaType: "image/jpeg" } }),
+  } }, "s"]]);
+  assert.equal(res.status, 200);
+  const set = res.body.methodResponses[0][1];
+  assert.equal(set.notCreated.blob.description, "blobIds in media is not supported.");
+  assert.deepEqual(set.notCreated.blob.properties, ["media"]);
+  assert.ok(set.created.inline.id, "a data URI is accepted");
+  await jmap([["ContactCard/set", { accountId: "a1", destroy: [set.created.inline.id] }, "d"]]);
+});
+
 test("an app password needs a name", async () => {
-  const res = await post("/api/account/app-passwords", { description: "   " });
+  const res = await post("/api/account/app-passwords", { description: "   ", current: "demo-password" });
  assert.equal(res.status, 400);
  assert.equal(res.body.error, "missing_fields");
 });
@@ -14,8 +14,18 @@ test("mail, calendars and the rest pass untouched", () => {
  assert.equal(r.ok, true);
 });

-test("the account's own registry objects pass", () => {
-  assert.equal(gateAdministration(req("x:AccountSettings/get", "x:AppPassword/set", "x:PublicKey/get", "x:MaskedEmail/set")).ok, true);
+test("the account's own registry objects can be read", () => {
+  assert.equal(gateAdministration(req("x:AccountSettings/get", "x:AppPassword/get", "x:PublicKey/get", "x:MaskedEmail/query")).ok, true);
+});
+
+test("but not written: a credential minted here would outlive a borrowed session", () => {
+  for (const m of ["x:AppPassword/set", "x:AccountPassword/set", "x:MaskedEmail/set"]) {
+    assert.deepEqual(gateAdministration(req("x:AccountSettings/get", m)), { ok: false, method: m });
+  }
+});
+
+test("API keys are not the account's to reach from here at all", () => {
+  assert.deepEqual(gateAdministration(req("x:ApiKey/get")), { ok: false, method: "x:ApiKey/get" });
 });

 test("directory and server objects are refused, and named", () => {
@@ -18,7 +18,7 @@
 * The standard JMAP methods (mail, calendars, contacts, files, sharing) are not
 * touched: they act on what the account can already reach.
 */
-const SELF_SERVICE = new Set(["AccountSettings", "AccountPassword", "AppPassword", "ApiKey", "PublicKey", "MaskedEmail"]);
+const SELF_SERVICE = new Set(["AccountSettings", "AccountPassword", "AppPassword", "PublicKey", "MaskedEmail"]);

 export type GateResult = { ok: true; body: string } | { ok: false; method: string | null };

@@ -83,8 +83,15 @@ export function gateAdministration(raw: string): GateResult {
    const name = Array.isArray(call) ? call[0] : undefined;
    if (typeof name !== "string") return { ok: false, method: null };
    if (!name.startsWith("x:")) continue;
-    const object = name.slice(2).split("/")[0] ?? "";
-    if (!SELF_SERVICE.has(object)) return { ok: false, method: name };
+    const [object = "", op = ""] = name.slice(2).split("/");
+    /*
+     * Read, never write. The browser sends none of these itself -- password,
+     * app-password and 2FA changes go through /api/account, which checks the
+     * account password first -- so a write here could only come from
+     * somebody working the console of a session on a borrowed machine, and
+     * `x:AppPassword/set` would hand them a credential that outlives it.
+     */
+    if (!SELF_SERVICE.has(object) || op === "set") return { ok: false, method: name };
  }
  return { ok: true, body: JSON.stringify(parsed) };
 }
@@ -1,6 +1,7 @@
 import { Hono } from "hono";
 import type { Context, MiddlewareHandler } from "hono";
 import { getCookie, setCookie, deleteCookie } from "hono/cookie";
+import { bodyLimit } from "hono/body-limit";
 import { compress } from "hono/compress";
 import { request as httpRequest } from "node:http";
 import { request as httpsRequest } from "node:https";
@@ -10,9 +11,10 @@ import { getConnInfo } from "@hono/node-server/conninfo";
 import { config } from "./config.js";
 import { fetchPermissions } from "./permissionSchema.js";
 import { administrationAllowed, gateAdministration, grantsAdministration } from "./adminGate.js";
-import { SessionStore, type SessionBackend, type LiveSession } from "./sessions.js";
+import { SessionStore, accountKey, type SessionBackend, type LiveSession } from "./sessions.js";
 import { RateLimiter } from "./ratelimit.js";
-import { resolveClientIp } from "./clientip.js";
+import { rateLimitKey, resolveClientIp } from "./clientip.js";
+import { safeEqual } from "./crypto.js";
 import {
  type AccountInfo,
  UpstreamError,
@@ -209,6 +211,22 @@ const csrfGuard: MiddlewareHandler = async (c, next) => {
  await next();
 };

+/**
+ * The largest body an API route that reads JSON will take.
+ *
+ * Hono reads a JSON body whole, and before this nothing bounded it: a few
+ * unauthenticated sign-in attempts carrying hundreds of megabytes each could
+ * run the process out of memory, and a restart signs everybody out. What
+ * these routes actually receive is a username and password, or a code.
+ *
+ * JMAP and uploads carry real payloads and bound themselves as they stream;
+ * the push callback has its own limit ahead of this one.
+ */
+const MAX_SMALL_BODY = 64 * 1024;
+const LARGE_BODY_ROUTE = /\/api\/(jmap$|upload\/)/;
+const limitSmallBody = bodyLimit({ maxSize: MAX_SMALL_BODY, onError: (c) => c.json({ error: "too_large" }, 413) });
+const smallBodies: MiddlewareHandler = (c, next) => (LARGE_BODY_ROUTE.test(c.req.path) ? next() : limitSmallBody(c, next));
+
 const requireSession: MiddlewareHandler<Env> = async (c, next) => {
  const cookie = getCookie(c, config.cookieName);
  const session = sessions.resolve(cookie);
@@ -269,6 +287,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {

  const api = new Hono<Env>();
  api.use("*", csrfGuard);
+  api.use("*", smallBodies);

  api.get("/health", (c) => c.json({ ok: true, name: config.appName, version: config.version, push: pushStatus() }));

@@ -303,6 +322,13 @@ export function createApp(basePath = config.basePath): Hono<Env> {
  // ---------- Auth ----------
  api.post("/auth/login", async (c) => {
    const ip = clientIp(c);
+    // What the limits count under: the address, or its /64 for IPv6.
+    const rateIp = rateLimitKey(ip);
+    // The flood ceiling needs nothing from the body, so it goes before reading one.
+    if (!loginFloodLimiter.check(rateIp)) {
+      c.header("Retry-After", String(loginFloodLimiter.retryAfterSeconds(rateIp)));
+      return c.json({ error: "rate_limited", message: "Too many login attempts. Please wait and try again." }, 429);
+    }
    let body: { username?: string; password?: string; totp?: string; remember?: boolean };
    try {
      body = await c.req.json();
@@ -318,7 +344,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {
    /*
     * Three checks, answering different questions.
     *
-     * `limitKey` is this username from this address, and `ip` is any username
+     * `limitKey` is this username from this address, and `rateIp` is any username
     * from it -- both guard guessing, and both are given back when the upstream
     * never got as far as judging the password. Refunding only the first would
     * not fix #239: ten retries through an outage would still spend the address
@@ -328,12 +354,8 @@ export function createApp(basePath = config.basePath): Hono<Env> {
     * The flood ceiling is the one that is never refunded, and it is the reason
     * the other two safely can be.
     */
-    const limitKey = `${ip}|${username.toLowerCase()}`;
-    if (!loginFloodLimiter.check(ip)) {
-      c.header("Retry-After", String(loginFloodLimiter.retryAfterSeconds(ip)));
-      return c.json({ error: "rate_limited", message: "Too many login attempts. Please wait and try again." }, 429);
-    }
-    if (!loginLimiter.check(limitKey) || !loginLimiter.check(ip)) {
+    const limitKey = `${rateIp}|${username.toLowerCase()}`;
+    if (!loginLimiter.check(limitKey) || !loginLimiter.check(rateIp)) {
      c.header("Retry-After", String(loginLimiter.retryAfterSeconds(limitKey)));
      return c.json({ error: "rate_limited", message: "Too many login attempts. Please wait and try again." }, 429);
    }
@@ -351,7 +373,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {
        // The credentials were accepted; only the server is too old. Not an
        // attempt worth counting against them.
        loginLimiter.refund(limitKey);
-        loginLimiter.refund(ip);
+        loginLimiter.refund(rateIp);
        return c.json(
          {
            error: "unsupported_server",
@@ -364,6 +386,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {
      loginLimiter.reset(limitKey);
      const { cookie, session } = sessions.create({
        username,
+        account: accountKey(upstreamFor(username), upstream.username || username),
        password: effectivePassword,
        remember: Boolean(body.remember),
        userAgent: c.req.header("user-agent") ?? "",
@@ -411,7 +434,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {
       */
      if (!(err instanceof UpstreamError && err.status === 401)) {
        loginLimiter.refund(limitKey);
-        loginLimiter.refund(ip);
+        loginLimiter.refund(rateIp);
      }
      return upstreamFailure(c, err);
    }
@@ -445,12 +468,12 @@ export function createApp(basePath = config.basePath): Hono<Env> {

  api.get("/auth/sessions", requireSession, (c) => {
    const session = c.get("session");
-    return c.json({ current: session.id, sessions: sessions.listForUser(session.username) });
+    return c.json({ current: session.id, sessions: sessions.listForUser(session.account) });
  });

  api.post("/auth/sessions/revoke-others", requireSession, (c) => {
    const session = c.get("session");
-    const n = sessions.destroyAllForUser(session.username, session.id);
+    const n = sessions.destroyAllForUser(session.account, session.id);
    return c.json({ revoked: n });
  });

@@ -478,8 +501,8 @@ export function createApp(basePath = config.basePath): Hono<Env> {
  };

  /** Guard the endpoints that check a password against brute-forcing. */
-  const guarded = (c: Context<Env>): Response | null => {
-    const key = `account|${c.get("session").username.toLowerCase()}`;
+  const guarded = (c: Context<Env>, scope = "account"): Response | null => {
+    const key = `${scope}|${c.get("session").username.toLowerCase()}`;
    if (accountLimiter.check(key)) return null;
    c.header("Retry-After", String(accountLimiter.retryAfterSeconds(key)));
    return c.json({ error: "rate_limited", message: "Too many attempts. Please wait and try again." }, 429);
@@ -517,7 +540,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {
    const otpCode = body.otpCode?.trim();
    sessions.reseal(getCookie(c, config.cookieName), otpCode ? `${next}$${otpCode}` : next);
    forgetUpstreamSession(session.id);
-    const revoked = sessions.destroyAllForUser(session.username, session.id);
+    const revoked = sessions.destroyAllForUser(session.account, session.id);
    return c.json({ ok: true, revokedSessions: revoked });
  });

@@ -531,12 +554,26 @@ export function createApp(basePath = config.basePath): Hono<Env> {
    }
  });

+  /*
+   * An app password is a credential that outlives this session, a password
+   * change and a sign-out -- so minting one asks for the account password, as
+   * changing the password does. Otherwise a session left open on somebody
+   * else's machine is enough to take a permanent key away from it.
+   */
  api.post("/account/app-passwords", requireSession, async (c) => {
+    // A budget of its own: guessing here never reaches Stalwart (see confirmsPassword).
+    const limited = guarded(c, "app-password");
+    if (limited) return limited;
    const session = c.get("session");
-    const body = await readJson<{ description?: string }>(c);
+    const body = await readJson<{ description?: string; current?: string }>(c);
    if (!body) return c.json({ error: "bad_request" }, 400);
    const description = (body.description ?? "").trim().slice(0, 120);
    if (!description) return c.json({ error: "missing_fields", message: "Give the app password a name." }, 400);
+    const current = body.current ?? "";
+    if (!current || current.length > 1024) return c.json({ error: "missing_fields", message: "Enter your current password." }, 400);
+    if (!(await confirmsPassword(session, current))) {
+      return c.json({ error: "invalid_credentials", message: "That password is not correct." }, 403);
+    }
    try {
      return c.json(await createAppPassword(await accountCtx(c), { description }));
    } catch (err) {
@@ -611,7 +648,7 @@ export function createApp(basePath = config.basePath): Hono<Env> {
      if (sessionKept) forgetUpstreamSession(session.id);
    }
    // Other sessions still hold the bare password and will be refused.
-    const revoked = sessions.destroyAllForUser(session.username, session.id);
+    const revoked = sessions.destroyAllForUser(session.account, session.id);
    return c.json({ ok: true, sessionKept, revokedSessions: revoked });
  });

@@ -648,12 +685,27 @@ export function createApp(basePath = config.basePath): Hono<Env> {
     */
    let body: ReadableStream<Uint8Array> | string | null = c.req.raw.body;
    if (!administrationAllowed(config.administration, session.remember)) {
+      const held = gatedReads.get(session.id) ?? 0;
+      if (held >= MAX_GATED_PER_SESSION) {
+        c.header("Retry-After", "1");
+        return c.json({ error: "rate_limited" }, 429);
+      }
+      gatedReads.set(session.id, held + 1);
      let raw: string;
      try {
+        if (Number(c.req.header("content-length") ?? "0") > MAX_GATED_REQUEST) return c.json({ error: "too_large" }, 413);
        // Counted as it arrives: a chunked body carries no length to refuse up front.
-        raw = c.req.raw.body ? await new Response(c.req.raw.body.pipeThrough(byteCap(MAX_GATED_REQUEST))).text() : "";
-      } catch {
+        raw = c.req.raw.body ? await readGated(c.req.raw.body) : "";
+      } catch (err) {
+        if (err instanceof GatedBudgetError) {
+          c.header("Retry-After", "1");
+          return c.json({ error: "busy" }, 503);
+        }
        return c.json({ error: "too_large" }, 413);
+      } finally {
+        const left = (gatedReads.get(session.id) ?? 1) - 1;
+        if (left > 0) gatedReads.set(session.id, left);
+        else gatedReads.delete(session.id);
      }
      const gate = gateAdministration(raw);
      if (!gate.ok) {
@@ -751,23 +803,30 @@ export function createApp(basePath = config.basePath): Hono<Env> {
    try {
      const upstream = await getUpstreamSession(session.id, session.authorization, upstreamFor(session.username));
      const url = absoluteUpstream(expandTemplate(upstream.downloadUrl, { accountId, blobId, name, type: accept }), upstream.baseUrl);
+      // A PDF viewer or a video element asks for pieces; pass that on. A server
+      // that ignores it answers with the whole file, as it did before.
+      const range = c.req.header("range");
      const res = await fetch(url, {
        // Ask for the bytes as they are. undici would otherwise negotiate gzip
        // on our behalf and hand back a decompressed body whose content-length
        // header still describes the compressed one -- see forwardedContentLength.
-        headers: { authorization: session.authorization, "accept-encoding": "identity" },
+        headers: { authorization: session.authorization, "accept-encoding": "identity", ...(range && /^bytes=[\d,\s-]+$/.test(range) ? { range } : {}) },
        signal: AbortSignal.timeout(Math.max(config.upstreamTimeout, 5 * 60_000)),
      });
+      if (res.status === 416) return c.body(null, 416);
      if (!res.ok) return c.json({ error: "not_found" }, res.status === 404 ? 404 : 502);
      const headers = new Headers();
      const type = sanitizeContentType(res.headers.get("content-type") ?? accept);
      headers.set("Content-Type", type);
      const cl = forwardedContentLength(res.headers);
      if (cl) headers.set("Content-Length", cl);
+      const partial = res.status === 206 && res.headers.get("content-range");
+      if (partial) headers.set("Content-Range", partial);
+      if (res.headers.get("accept-ranges") === "bytes") headers.set("Accept-Ranges", "bytes");
      const safeInline = inline && isInlineSafe(type);
      headers.set(
        "Content-Disposition",
-        `${safeInline ? "inline" : "attachment"}; filename*=UTF-8''${encodeURIComponent(name)}`,
+        `${safeInline ? "inline" : "attachment"}; filename*=UTF-8''${encodeURIComponent(withoutBidiControls(name))}`,
      );
      headers.set("X-Content-Type-Options", "nosniff");
      // Sandbox everything except the browser's built-in PDF viewer (which needs scripts to render).
@@ -786,8 +845,15 @@ export function createApp(basePath = config.basePath): Hono<Env> {
      } else {
        headers.set("Content-Security-Policy", "sandbox; default-src 'none'; style-src 'unsafe-inline'; img-src data:");
      }
-      headers.set("Cache-Control", "private, max-age=3600");
-      return new Response(res.body, { status: 200, headers });
+      // Kept out of the browser's disk cache on a device that is not the
+      // person's own: signing out wipes what the app stores, not that.
+      /*
+       * A blob id names its content -- the same id is the same bytes for good
+       * -- so on the reader's own device there is nothing to revalidate. On
+       * anyone else's, nothing is left in the disk cache at all.
+       */
+      headers.set("Cache-Control", session.remember ? "private, max-age=31536000, immutable" : "no-store");
+      return new Response(res.body, { status: partial ? 206 : 200, headers });
    } catch (err) {
      return upstreamFailure(c, err);
    }
@@ -872,6 +938,43 @@ async function readJson<T>(c: Context): Promise<T | null> {
  }
 }

+/**
+ * Is `candidate` the password of the account this session is signed in to?
+ *
+ * Compared with the credential the session holds first, which costs nothing
+ * and tells Stalwart nothing -- its auto-ban counts failures against the
+ * proxy's address, which every user shares. That credential is the password,
+ * with a TOTP code after a `$` when one was given at sign-in. A session that
+ * turning on 2FA moved onto an app password (Stalwart's secrets start
+ * `$app$`) holds something else, and only then is the candidate put to the
+ * server.
+ */
+async function confirmsPassword(session: LiveSession, candidate: string): Promise<boolean> {
+  const decoded = Buffer.from(session.authorization.replace(/^Basic /, ""), "base64").toString("utf8");
+  const held = decoded.slice(decoded.indexOf(":") + 1);
+  if (safeEqual(held, candidate)) return true;
+  const withoutCode = held.replace(/\$\d{6,8}$/, "");
+  if (withoutCode !== held && safeEqual(withoutCode, candidate)) return true;
+  // Holding the password, the comparison above is the answer, and a wrong
+  // guess never reaches the server's auto-ban.
+  if (!held.startsWith("$app$")) return false;
+  try {
+    const authorization = `Basic ${Buffer.from(`${session.username}:${candidate}`, "utf8").toString("base64")}`;
+    await fetchUpstreamSession(authorization, upstreamFor(session.username));
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+/**
+ * Direction overrides and isolates, which can make `Invoice_\u202Efdp.exe`
+ * read as a PDF in the downloads list. A filename has no use for them.
+ */
+function withoutBidiControls(name: string): string {
+  return name.replace(/[\u061C\u200E\u200F\u202A-\u202E\u2066-\u2069]/g, "");
+}
+
 /** Name the app password after the browser it will live in. */
 function appPasswordName(c: Context): string {
  const ua = c.req.header("user-agent") ?? "";
@@ -931,9 +1034,50 @@ function sessionExtras(session: LiveSession, info: AccountInfo = { locale: null,
 */
 /**
 * The largest JMAP request read into memory for the administration check.
- * Stalwart's own default `maxSizeRequest` is 10 MB; uploads never come this way.
+ *
+ * Only sessions that may not administer come this way, and what the client
+ * sends is small: attachments and pasted images go through `/upload`, and the
+ * composer turns inline images into uploads before a draft is saved. Stalwart
+ * would take up to its `maxSizeRequest` (10 MB by default), but a request is
+ * held here as a string, parsed and serialized again, so each one costs
+ * several times its size; 4 MB is far past anything the client sends.
 */
-const MAX_GATED_REQUEST = 16 * 1024 * 1024;
+const MAX_GATED_REQUEST = 4 * 1024 * 1024;
+/**
+ * How many checked requests one session may have in flight at once. Matches
+ * the `maxConcurrentRequests` Stalwart advertises by default, which the client
+ * already stays within.
+ */
+const MAX_GATED_PER_SESSION = 4;
+/**
+ * The bytes all checked requests together may hold at once. Counted as they
+ * arrive rather than reserved up front, so a slow body that has sent little
+ * holds little, and a burst of large ones is turned away with a 503 instead of
+ * taking the process down.
+ */
+const GATED_BUDGET = 32 * 1024 * 1024;
+const gatedReads = new Map<string, number>();
+let gatedBytes = 0;
+
+class GatedBudgetError extends Error {}
+
+async function readGated(stream: ReadableStream<Uint8Array>): Promise<string> {
+  let mine = 0;
+  const counted = new TransformStream<Uint8Array, Uint8Array>({
+    transform(chunk, controller) {
+      mine += chunk.byteLength;
+      gatedBytes += chunk.byteLength;
+      if (mine > MAX_GATED_REQUEST) controller.error(new Error("request too large"));
+      else if (gatedBytes > GATED_BUDGET) controller.error(new GatedBudgetError("gated read budget spent"));
+      else controller.enqueue(chunk);
+    },
+  });
+  try {
+    return await new Response(stream.pipeThrough(counted)).text();
+  } finally {
+    gatedBytes -= mine;
+  }
+}

 const PASSTHROUGH_HEADERS = new Set(["content-type", "content-disposition", "content-language", "etag", "last-modified", "retry-after"]);

@@ -97,3 +97,21 @@ export function resolveClientIp(peer: string, headers: ForwardHeaders, cfg: Trus
  const real = headers.realIp?.trim();
  return real && isIP(real) !== 0 ? real : peer;
 }
+
+/**
+ * The key a rate limit counts an address under.
+ *
+ * An IPv4 address is the key as it is. An IPv6 address is cut to its /64: that
+ * is the smallest block an ISP or a VPS hands out, so anyone who holds one
+ * address holds 2^64 of them, and a limit keyed on the full address is no
+ * limit. Everyone behind one /64 shares a budget, which is the same bargain an
+ * IPv4 NAT already makes.
+ */
+export function rateLimitKey(ip: string): string {
+  if (isIP(ip) !== 6) return ip;
+  const bits = toBits(ip);
+  if (!bits) return ip;
+  const prefix = bits.value >> 64n;
+  const groups = [48n, 32n, 16n, 0n].map((s) => ((prefix >> s) & 0xffffn).toString(16));
+  return `${groups.join(":")}::/64`;
+}
@@ -217,7 +217,8 @@ export async function imageProxyHandler(c: Context) {
  res.on("close", done);
  const headers = new Headers({
    "Content-Type": type,
-    "Cache-Control": "private, max-age=86400",
+    // As for attachments: nothing left in the disk cache of a device that is not the person's own.
+    "Cache-Control": (c.get("session") as { remember?: boolean } | undefined)?.remember ? "private, max-age=86400" : "no-store",
    "X-Content-Type-Options": "nosniff",
    "Content-Security-Policy": "sandbox; default-src 'none'",
    "Cross-Origin-Resource-Policy": "same-origin",
@@ -0,0 +1,9 @@
+import { account } from "./config.js";
+import { parseOtpauthUrl, verifyTotp } from "../totp.js";
+
+/* Shared by the HTTP layer and by the handlers that re-check a code. */
+export function checkOtp(code: string | undefined): boolean {
+  if (!account.otpUrl) return true;
+  const params = parseOtpauthUrl(account.otpUrl);
+  return Boolean(code && params && verifyTotp(params, code));
+}
@@ -0,0 +1,51 @@
+import { readFileSync } from "node:fs";
+
+
+export const PERMISSION_SNAPSHOT = (JSON.parse(readFileSync(new URL("../../../web/src/locales/permissions/source.json", import.meta.url), "utf8")) as { permissions: Array<{ name: string; label: string }> }).permissions;
+
+export const PORT = Number(process.env.MOCK_PORT ?? 8788);
+/**
+ * Omit `urn:stalwart:jmap` from the session, so a sign-in can be tested
+ * against a server ihasmail does not support. This is only that: the rest of
+ * the mock still behaves like 0.16. Emulating 0.15 properly went with the
+ * support for it.
+ */
+export const NO_REGISTRY = process.env.MOCK_NO_REGISTRY === "1";
+/**
+ * Stalwart advertises FUTURERELEASE in the session but only honors it when
+ * the MTA's own `futureRelease` setting is on -- and that setting defaults to
+ * off, in which case the hold is dropped without a word and the message goes
+ * out at once. Set MOCK_NO_FUTURE_RELEASE=1 to reproduce that trap.
+ */
+export const NO_FUTURE_RELEASE = process.env.MOCK_NO_FUTURE_RELEASE === "1";
+/** What the session advertises, matching Stalwart's own 30 days. */
+export const MAX_DELAYED_SEND = 86400 * 30;
+export const ACCOUNT = "a1";
+/** How long a push subscription lives before the server drops it. */
+export const PUSH_TTL_MS = 7 * 24 * 60 * 60 * 1000;
+/** An account somebody has shared with the demo user. See the session below. */
+export const SHARED_ACCOUNT = "a2";
+export const SHARED_CAPS: Obj = {
+  "urn:ietf:params:jmap:mail": {}, "urn:ietf:params:jmap:submission": {}, "urn:ietf:params:jmap:vacationresponse": {},
+  "urn:ietf:params:jmap:sieve": {}, "urn:ietf:params:jmap:calendars": {}, "urn:ietf:params:jmap:contacts": {},
+  "urn:ietf:params:jmap:principals": {}, "urn:ietf:params:jmap:quota": {}, "urn:ietf:params:jmap:filenode": {},
+};
+export const USER = process.env.MOCK_USER ?? "[email protected]";
+/** Locale the fake directory reports for the account (POSIX style, as Stalwart does). */
+export const MOCK_LOCALE = process.env.MOCK_LOCALE ?? "en_US";
+/** What /api/account reports. Tenants are managed only on "enterprise"; MOCK_EDITION=enterprise to develop them. */
+export const MOCK_EDITION = process.env.MOCK_EDITION ?? "oss";
+export const PASS = process.env.MOCK_PASS ?? "demo";
+/**
+ * Credential state, mutable so the self-service flows can be exercised against
+ * the mock the way they run against a real 0.16 server: the password changes,
+ * 2FA starts demanding a code on every request, and app passwords keep working
+ * without one.
+ */
+export const account = { password: PASS, otpUrl: null as string | null, appPasswords: [] as Obj[] };
+export const MASKED = "[********]";
+
+export type Obj = Record<string, unknown>;
+export const state = { n: 1 };
+export const nextState = () => String(state.n++);
+
@@ -0,0 +1,410 @@
+import { randomUUID } from "node:crypto";
+import { signedMessage, type SIGNED_MESSAGES } from "./signedMessages.js";
+import { Obj, SHARED_ACCOUNT, USER, account } from "./config.js";
+
+/* ---------- data ---------- */
+/*
+ * The names are Stalwart's own defaults, which follow the Exchange convention:
+ * "Deleted Items" and "Sent Items", not "Trash" and "Sent". The mock used the
+ * short forms, so anything built from a folder's name read differently here
+ * than in production -- "Empty Trash" against the mock, "Empty Deleted Items"
+ * against a real server -- and every screenshot in the README showed a folder
+ * list no user has. The role is what the client branches on; the name is only
+ * ever displayed, which is exactly why it has to look right.
+ */
+/** Push subscriptions, as a fresh account has none. */
+export const pushSubscriptions: Obj[] = [];
+
+export const mailboxes: Obj[] = [
+  mb("inbox", "Inbox", "inbox"),
+  mb("drafts", "Drafts", "drafts"),
+  mb("sent", "Sent Items", "sent"),
+  mb("junk", "Junk Mail", "junk"),
+  mb("trash", "Deleted Items", "trash"),
+  mb("archive", "Archive", "archive"),
+  mb("work", "Work", null),
+  mb("work-inv", "Invoices", null, "work"),
+  mb("news", "Newsletters", null),
+];
+export function mb(id: string, name: string, role: string | null, parentId: string | null = null): Obj {
+  return { id, name, parentId, role, sortOrder: 0, totalEmails: 0, unreadEmails: 0, totalThreads: 0, unreadThreads: 0, isSubscribed: true, myRights: { mayReadItems: true, mayAddItems: true, mayRemoveItems: true, maySetSeen: true, maySetKeywords: true, mayCreateChild: true, mayRename: true, mayDelete: true, maySubmit: true } };
+}
+
+export const blobs = new Map<string, { type: string; data: Buffer }>();
+export function putBlob(data: Buffer | string, type: string): string {
+  const id = `b${randomUUID().slice(0, 8)}`;
+  blobs.set(id, { type, data: Buffer.isBuffer(data) ? data : Buffer.from(data) });
+  return id;
+}
+
+export const people = [
+  ["Ada Lovelace", "[email protected]"], ["Grace Hopper", "[email protected]"], ["Linus Torvalds", "[email protected]"],
+  ["Margaret Hamilton", "[email protected]"], ["Alan Turing", "[email protected]"], ["GitHub", "[email protected]"],
+  ["Stalwart Labs", "[email protected]"], ["Weekly Digest", "[email protected]"], ["Finance Team", "[email protected]"],
+];
+export const subjects = [
+  "Re: Q3 planning document", "Your invoice #4821 is ready", "Welcome to Stalwart!", "Lunch on Thursday?", "[PR] Fix push reconnect backoff",
+  "Weekly digest: 12 new articles", "Photos from the hike", "Deployment window this weekend", "Contract draft v3 attached", "Can you review my slides?",
+  "Reminder: dentist appointment", "Flight confirmation – BOS → SFO", "Team offsite agenda", "Re: Re: budget approval", "Security notice: new sign-in",
+];
+export const emails: Obj[] = [];
+export const seq = { counter: 1 };
+/**
+ * A real TNEF blob, built to the format description, so the winmail.dat
+ * decoder has something to open that is not a hand-made fixture in its own
+ * test file. Two files inside, one of them carrying a long name in the MAPI
+ * stream behind an 8.3 title -- which is the case the decoder exists for.
+ */
+export function winmailDat(): Buffer {
+  const u16 = (v: number) => Buffer.from([v & 0xff, (v >> 8) & 0xff]);
+  const u32 = (v: number) => Buffer.from([v & 0xff, (v >> 8) & 0xff, (v >> 16) & 0xff, (v >>> 24) & 0xff]);
+  const sum = (b: Buffer) => { let n = 0; for (const x of b) n = (n + x) & 0xffff; return n; };
+  const attr = (level: number, id: number, data: Buffer) => Buffer.concat([Buffer.from([level]), u32(id), u32(data.length), data, u16(sum(data))]);
+  const asciiProp = (id: number, value: string) => {
+    const bytes = Buffer.concat([Buffer.from(value, "latin1"), Buffer.from([0])]);
+    const pad = Buffer.alloc((4 - (bytes.length % 4)) % 4);
+    return Buffer.concat([u32(((id & 0xffff) << 16) | 0x001e), u32(bytes.length), bytes, pad]);
+  };
+  const mapi = (props: Buffer[]) => Buffer.concat([u32(props.length), ...props]);
+
+  const renddata = Buffer.alloc(14);
+  const title = (n: string) => Buffer.concat([Buffer.from(n, "latin1"), Buffer.from([0])]);
+  const notes = Buffer.from("Numbers pulled from the mock, not from anywhere real.\n", "latin1");
+  const csv = Buffer.from("quarter,revenue\nQ1,120\nQ2,145\n", "latin1");
+
+  return Buffer.concat([
+    u32(0x223e9f78), u16(0x1234),
+    attr(1, 0x00089006, u32(0x00010000)), // attTnefVersion
+    attr(2, 0x00069002, renddata),
+    attr(2, 0x00018010, title("QUARTE~1.CSV")),
+    attr(2, 0x00069005, mapi([asciiProp(0x3707, "Quarterly Revenue Final.csv"), asciiProp(0x370e, "text/csv")])),
+    attr(2, 0x0006800f, csv),
+    attr(2, 0x00069002, renddata),
+    attr(2, 0x00018010, title("notes.txt")),
+    attr(2, 0x0006800f, notes),
+  ]);
+}
+
+/**
+ * A really signed message, served as the raw blob a client verifies against.
+ *
+ * The signature is over exact bytes, so this deliberately does not go through
+ * addEmail: that builds a message out of parts and would hand back a body it
+ * had assembled rather than the one that was signed. Here the blob *is* the
+ * fixture, byte for byte, and the JMAP metadata is arranged around it.
+ *
+ * `bodyStructure` says multipart/signed because that is what the client checks
+ * before deciding to download anything -- a mock that omitted it would leave
+ * the whole path unreachable while every stored byte was still correct.
+ */
+export function addSignedEmail(o: { which: keyof typeof SIGNED_MESSAGES; from: [string, string]; subject: string; daysAgo: number; mailbox: string; unread?: boolean }) {
+  const id = `e${seq.counter++}`;
+  const raw = signedMessage(o.which);
+  const received = new Date(Date.now() - o.daysAgo * 86400_000).toISOString().replace(/\.\d{3}Z$/, "Z");
+  const body = "The Analytical Engine has no pretensions whatever to originate anything.";
+  const textBlob = putBlob(body, "text/plain");
+  const e: Obj = {
+    id,
+    blobId: putBlob(raw, "message/rfc822"),
+    threadId: `t${id}`,
+    mailboxIds: { [o.mailbox]: true },
+    keywords: o.unread ? {} : { $seen: true },
+    size: raw.length,
+    receivedAt: received,
+    sentAt: received,
+    messageId: [`${id}@mock`],
+    inReplyTo: null,
+    references: null,
+    from: [{ name: o.from[0], email: o.from[1] }],
+    to: [{ name: "Demo User", email: USER }],
+    cc: null, bcc: null, replyTo: null, sender: null,
+    subject: o.subject,
+    hasAttachment: false,
+    preview: body.slice(0, 120),
+    textBody: [{ partId: "1", blobId: textBlob, size: body.length, name: null, type: "text/plain", charset: "utf-8", disposition: null, cid: null }],
+    htmlBody: [],
+    attachments: [],
+    bodyValues: { "1": { value: body, isEncodingProblem: false, isTruncated: false } },
+    bodyStructure: {
+      partId: null, blobId: null, size: raw.length, type: "multipart/signed", name: null, charset: null, disposition: null, cid: null,
+      subParts: [
+        { partId: "1", blobId: textBlob, size: body.length, type: "text/plain", name: null, charset: "utf-8", disposition: null, cid: null },
+        { partId: "2", blobId: null, size: 0, type: "application/x-pkcs7-signature", name: "smime.p7s", charset: null, disposition: "attachment", cid: null },
+      ],
+    },
+  };
+  emails.push(e);
+  return e;
+}
+
+/*
+ * A marketing template of the shape #290 was reported against.
+ *
+ * Nothing in it is unusual — an outer 600px wrapper on `bgcolor="#ffffff"`, a
+ * `<style>` block, a colored call to action, a gray footer — and that is the
+ * point. Every one of those is enough to make `htmlDeclaresColors` true, so a
+ * mock without one could not show what "apply the theme to messages too" does
+ * to the mail people actually receive: nothing at all.
+ */
+export const STYLED_MARKETING_HTML = `<html><head><style>
+  a { color:#1155CC; text-decoration:underline }
+  .h { font-size:20px; color:#111111 }
+</style></head><body style="margin:0;background-color:#f4f4f4">
+<table width="100%" bgcolor="#f4f4f4" cellpadding="0" cellspacing="0"><tr><td align="center">
+  <table width="600" bgcolor="#ffffff" cellpadding="0" cellspacing="0" style="background-color:#ffffff">
+    <tr><td style="padding:24px"><p class="h">Your order is on its way</p>
+      <p style="color:#333333">Thanks for shopping with us. Your parcel left the warehouse this morning.</p>
+      <table cellpadding="0" cellspacing="0"><tr>
+        <td bgcolor="#1155CC" style="border-radius:4px;padding:12px 20px">
+          <a href="https://example.com/track" style="color:#FFFFFF;text-decoration:none">Track your parcel</a>
+        </td></tr></table>
+      <p style="color:#666666;font-size:12px">Order #4471 &middot; placed 2 September</p>
+    </td></tr>
+    <tr><td bgcolor="#222222" style="padding:16px;color:#dddddd;font-size:12px">
+      You are receiving this because you bought something. <a href="https://example.com/x" style="color:#88bbff">Unsubscribe</a>
+    </td></tr>
+  </table>
+</td></tr></table></body></html>`;
+
+export function addEmail(o: { from: [string, string]; to?: string; subject: string; daysAgo: number; mailbox: string; threadId?: string; unread?: boolean; flagged?: boolean; html?: boolean; styled?: boolean; attach?: boolean; winmail?: boolean; inReplyTo?: string }) {
+  const id = `e${seq.counter++}`;
+  const received = new Date(Date.now() - o.daysAgo * 86400_000 - Math.random() * 3600_000 * 5).toISOString().replace(/\.\d{3}Z$/, "Z");
+  const text = `Hi,\n\nThis is a sample message about "${o.subject}". It was generated by the ihasmail mock server so you can try the interface without a real mailbox.\n\nSome highlights:\n- Keyboard shortcuts (press ? )\n- Conversation view\n- Drag & drop to folders\n\nCheers,\n${o.from[0]}\n\n> On Monday, someone wrote:\n> This is the quoted part of an earlier message.\n> It should be collapsed by default.`;
+  const html = `<html><body style="font-family:Arial"><p>Hi,</p><p>This is a <b>sample HTML message</b> about “${o.subject}”. It was generated by the ihasmail mock server.</p><ul><li>Keyboard shortcuts (press ?)</li><li>Conversation view</li><li><a href="https://stalw.art">Drag &amp; drop</a> to folders</li></ul><p><img src="https://example.com/tracker.gif" width="1" height="1" alt=""> <img src="cid:logo@mock" width="120" alt="logo"></p><p>Cheers,<br>${o.from[0]}</p><div class="gmail_quote">On Monday, someone wrote:<blockquote>This is the quoted part of an earlier message. It should be collapsed by default.</blockquote></div></body></html>`;
+  const textBlob = putBlob(text, "text/plain");
+  const htmlBlob = putBlob(o.styled ? STYLED_MARKETING_HTML : html, "text/html");
+  const attachments: Obj[] = [];
+  if (o.attach) {
+    attachments.push({ partId: "3", blobId: putBlob("%PDF-1.4 mock", "application/pdf"), size: 48213, name: "contract-v3.pdf", type: "application/pdf", charset: null, disposition: "attachment", cid: null });
+    attachments.push({ partId: "4", blobId: putBlob(Buffer.from("iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNkYPhfDwAChwGA60e6kgAAAABJRU5ErkJggg==", "base64"), "image/png"), size: 68, name: "pixel.png", type: "image/png", charset: null, disposition: "attachment", cid: null });
+  }
+  if (o.winmail) {
+    const dat = winmailDat();
+    attachments.push({ partId: "6", blobId: putBlob(dat, "application/ms-tnef"), size: dat.length, name: "winmail.dat", type: "application/ms-tnef", charset: null, disposition: "attachment", cid: null });
+  }
+  if (o.html) attachments.push({ partId: "5", blobId: putBlob(Buffer.from("iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP4z8DwHwAFAAH/q842iQAAAABJRU5ErkJggg==", "base64"), "image/png"), size: 68, name: "logo.png", type: "image/png", charset: null, disposition: "inline", cid: "logo@mock" });
+  const e: Obj = {
+    id, blobId: putBlob(`From: ${o.from[0]} <${o.from[1]}>\r\nTo: ${USER}\r\nSubject: ${o.subject}\r\nDate: ${received}\r\nMessage-ID: <${id}@mock>\r\n\r\n${text}`, "message/rfc822"),
+    threadId: o.threadId ?? `t${id}`, mailboxIds: { [o.mailbox]: true },
+    keywords: { ...(o.unread ? {} : { $seen: true }), ...(o.flagged ? { $flagged: true } : {}) },
+    size: 4000 + Math.floor(Math.random() * 20000), receivedAt: received, sentAt: received,
+    messageId: [`${id}@mock`], inReplyTo: o.inReplyTo ? [o.inReplyTo] : null, references: o.inReplyTo ? [o.inReplyTo] : null,
+    from: [{ name: o.from[0], email: o.from[1] }], to: [{ name: "Demo User", email: o.to ?? USER }], cc: null, bcc: null, replyTo: null, sender: null,
+    subject: o.subject, hasAttachment: Boolean(o.attach), preview: text.slice(0, 120).replace(/\n/g, " "),
+    textBody: [{ partId: "1", blobId: textBlob, size: text.length, name: null, type: "text/plain", charset: "utf-8", disposition: null, cid: null }],
+    htmlBody: o.html ? [{ partId: "2", blobId: htmlBlob, size: (o.styled ? STYLED_MARKETING_HTML : html).length, name: null, type: "text/html", charset: "utf-8", disposition: null, cid: null }] : [],
+    attachments,
+    bodyValues: { "1": { value: text, isEncodingProblem: false, isTruncated: false }, ...(o.html ? { "2": { value: o.styled ? STYLED_MARKETING_HTML : html, isEncodingProblem: false, isTruncated: false } } : {}) },
+    bodyStructure: { partId: null, blobId: null, size: 0, type: "multipart/mixed", name: null, charset: null, disposition: null, cid: null, subParts: [{ partId: "1", blobId: textBlob, size: text.length, type: "text/plain", name: null, charset: "utf-8", disposition: null, cid: null }, ...(o.html ? [{ partId: "2", blobId: htmlBlob, size: (o.styled ? STYLED_MARKETING_HTML : html).length, type: "text/html", name: null, charset: "utf-8", disposition: null, cid: null }] : []), ...attachments] },
+    "header:List-Unsubscribe:asText": o.from[1].includes("newsletter") ? "<mailto:[email protected]?subject=unsubscribe>, <https://newsletter.example/unsub>" : null,
+    "header:X-Priority:asText": o.subject.startsWith("Security") ? "1 (Highest)" : null,
+    // Stalwart's spam filter writes the SpamAssassin-shaped set at delivery, so
+    // delivered mail carries it and mail this account wrote does not.
+    "header:X-Spam-Status:asText":
+      o.mailbox === "junk"
+        ? "Yes, score=14.2 required=5.0 tests=[BAYES_99=3.5, URIBL_BLOCKED=2.7, HTML_IMAGE_ONLY=1.4, SUBJ_ALL_CAPS=1.2, FROM_FREEMAIL=0.4] autolearn=no"
+        : o.mailbox === "inbox"
+          ? "No, score=-1.8 required=5.0 tests=[BAYES_00=-1.9, DKIM_VALID=-0.7, SPF_PASS=-0.1, HTML_MESSAGE=0.9]"
+          : null,
+  };
+  emails.push(e);
+  return e;
+}
+// Seed
+for (let i = 0; i < 45; i++) {
+  const p = people[i % people.length]!;
+  const subj = subjects[i % subjects.length]!;
+  const e = addEmail({ from: [p[0]!, p[1]!], subject: subj, daysAgo: i * 0.7, mailbox: i % 9 === 8 ? "news" : i % 11 === 10 ? "work" : "inbox", unread: i % 3 === 0, flagged: i % 7 === 0, html: i % 2 === 0, attach: i % 5 === 0 });
+  if (i % 4 === 0) {
+    // thread replies
+    addEmail({ from: ["Demo User", USER], to: p[1]!, subject: `Re: ${subj}`, daysAgo: i * 0.7 - 0.2, mailbox: "sent", threadId: e.threadId as string, inReplyTo: `${e.id}@mock`, html: true });
+    addEmail({ from: [p[0]!, p[1]!], subject: `Re: ${subj}`, daysAgo: i * 0.7 - 0.4, mailbox: "inbox", threadId: e.threadId as string, unread: i % 8 === 0, inReplyTo: `${e.id}@mock`, html: i % 3 === 0 });
+  }
+}
+addEmail({ from: ["Shop Updates", "[email protected]"], subject: "Your order is on its way", daysAgo: 0.3, mailbox: "inbox", html: true, styled: true });
+addEmail({ from: ["Demo User", USER], to: "[email protected]", subject: "Draft: ideas for the retreat", daysAgo: 0.1, mailbox: "drafts", html: true }).keywords = { $draft: true, $seen: true };
+
+/*
+ * Three signed messages, so every branch of the signature banner can be seen
+ * without staging a certificate authority. Read "A note" first: that pins Ada's
+ * certificate, after which the other two have something to disagree with.
+ */
+addSignedEmail({ which: "good", from: ["Ada Lovelace", "[email protected]"], subject: "A note", daysAgo: 0.2, mailbox: "inbox", unread: true });
+addSignedEmail({ which: "tampered", from: ["Ada Lovelace", "[email protected]"], subject: "A note (altered in transit)", daysAgo: 0.25, mailbox: "inbox", unread: true });
+addSignedEmail({ which: "imposter", from: ["Ada Lovelace", "[email protected]"], subject: "A note (signed by somebody else)", daysAgo: 0.3, mailbox: "inbox", unread: true });
+addEmail({ from: ["Spammy", "[email protected]"], subject: "You have WON!!!", daysAgo: 2, mailbox: "junk", unread: true });
+addEmail({ from: ["Outlook User", "[email protected]"], subject: "Q3 figures (sent from Outlook)", daysAgo: 1, mailbox: "inbox", unread: true, winmail: true });
+addEmail({ from: ["Finance Team", "[email protected]"], subject: "Invoice 2201 approved", daysAgo: 1, mailbox: "work-inv", unread: true });
+addEmail({ from: ["Finance Team", "[email protected]"], subject: "Invoice 2202 pending", daysAgo: 2, mailbox: "work-inv", unread: true });
+// A thread whose unread message is not the last one: someone's server queued
+// their reply for hours, so it landed after messages that answer it and sits in
+// the middle of the conversation. Opening this thread at the newest message
+// left that reply above the fold until the mark-read timer swept it (#87).
+{
+  const subj = "Compiler timings for the release";
+  const t = addEmail({ from: ["Grace Hopper", "[email protected]"], subject: subj, daysAgo: 6, mailbox: "inbox", html: true });
+  const tid = t.threadId as string;
+  const reply = (o: { from: [string, string]; daysAgo: number; mailbox: string; to?: string; unread?: boolean; html?: boolean }) =>
+    addEmail({ ...o, subject: `Re: ${subj}`, threadId: tid, inReplyTo: `${t.id}@mock` });
+  reply({ from: ["Alan Turing", "[email protected]"], daysAgo: 5.5, mailbox: "inbox", unread: true });
+  // Long enough after the unread one that the thread scrolls: opening at the
+  // bottom put four messages between the reader and the mail they had not read.
+  reply({ from: ["Demo User", USER], to: "[email protected]", daysAgo: 5, mailbox: "sent", html: true });
+  reply({ from: ["Grace Hopper", "[email protected]"], daysAgo: 4.5, mailbox: "inbox" });
+  reply({ from: ["Margaret Hamilton", "[email protected]"], daysAgo: 4, mailbox: "inbox", html: true });
+  reply({ from: ["Demo User", USER], to: "[email protected]", daysAgo: 3.5, mailbox: "sent" });
+  reply({ from: ["Grace Hopper", "[email protected]"], daysAgo: 3, mailbox: "inbox", html: true });
+}
+// Invitation email
+{
+  const ics = `BEGIN:VCALENDAR\r\nVERSION:2.0\r\nPRODID:-//mock//EN\r\nMETHOD:REQUEST\r\nBEGIN:VEVENT\r\nUID:inv-1@mock\r\nDTSTAMP:20260820T100000Z\r\nDTSTART:20260825T140000Z\r\nDTEND:20260825T150000Z\r\nSUMMARY:Project kickoff\r\nORGANIZER;CN=Ada Lovelace:mailto:[email protected]\r\nATTENDEE;CN=Demo User;RSVP=TRUE;PARTSTAT=NEEDS-ACTION:mailto:${USER}\r\nLOCATION:Room 4B\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n`;
+  const e = addEmail({ from: ["Ada Lovelace", "[email protected]"], subject: "Invitation: Project kickoff", daysAgo: 0.3, mailbox: "inbox", unread: true });
+  const b = putBlob(ics, "text/calendar");
+  (e.bodyStructure as Obj).subParts = [...((e.bodyStructure as Obj).subParts as Obj[]), { partId: "9", blobId: b, size: ics.length, type: "text/calendar", name: "invite.ics", charset: "utf-8", disposition: "attachment", cid: null }];
+  (e.attachments as Obj[]).push({ partId: "9", blobId: b, size: ics.length, type: "text/calendar", name: "invite.ics", charset: "utf-8", disposition: "attachment", cid: null });
+  e.hasAttachment = true;
+}
+
+export const identities: Obj[] = [
+  { id: "i1", name: "Demo User", email: USER, replyTo: null, bcc: null, textSignature: "-- \nDemo User\nihasmail", htmlSignature: "<div>-- <br><b>Demo User</b><br>ihasmail</div>", mayDelete: false },
+  { id: "i2", name: "Demo (alias)", email: "[email protected]", replyTo: null, bcc: null, textSignature: "", htmlSignature: "", mayDelete: true },
+];
+export const vacationBox: { current: Obj } = { current: { id: "singleton", isEnabled: false, fromDate: null, toDate: null, subject: null, textBody: null, htmlBody: null } };
+export const sieveScripts: Obj[] = [];
+/* A calendar in the shared account, so "Shared with me" and a colleague's
+   events appearing in the grid can be exercised. Read-only, as a share is. */
+export const sharedCalendars: Obj[] = [{ id: "c9", name: "Grace — Work", description: null, color: "#c084fc", sortOrder: 0, isSubscribed: false, isVisible: true, isDefault: true, includeInAvailability: "all", defaultAlertsWithTime: null, defaultAlertsWithoutTime: null, timeZone: "UTC", shareWith: {}, myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: false, mayWriteOwn: false, mayUpdatePrivate: false, mayRSVP: false, mayShare: false, mayDelete: false } }];
+export const sharedEvents: Obj[] = [];
+export const eventsFor = (accountId: unknown): Obj[] => (accountId === SHARED_ACCOUNT ? sharedEvents : events);
+export const calendarsFor = (accountId: unknown): Obj[] => (accountId === SHARED_ACCOUNT ? sharedCalendars : calendars);
+export const calendars: Obj[] = [{ id: "c1", name: "Personal", description: null, color: "#0f766e", sortOrder: 0, isSubscribed: true, isVisible: true, isDefault: true, includeInAvailability: "all", defaultAlertsWithTime: null, defaultAlertsWithoutTime: null, timeZone: "UTC", shareWith: null, myRights: rightsCal() }, { id: "c2", name: "Work", description: null, color: "#2563eb", sortOrder: 1, isSubscribed: true, isVisible: true, isDefault: false, includeInAvailability: "all", defaultAlertsWithTime: null, defaultAlertsWithoutTime: null, timeZone: "UTC", shareWith: null, myRights: rightsCal() }];
+export function rightsCal() { return { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayShare: true, mayDelete: true }; }
+export const events: Obj[] = [];
+{
+  const now = new Date();
+  const d = (dayOff: number, h: number) => { const x = new Date(now.getFullYear(), now.getMonth(), now.getDate() + dayOff, h, 0, 0); return x; };
+  const local = (x: Date) => `${x.getFullYear()}-${String(x.getMonth() + 1).padStart(2, "0")}-${String(x.getDate()).padStart(2, "0")}T${String(x.getHours()).padStart(2, "0")}:00:00`;
+  const tz = Intl.DateTimeFormat().resolvedOptions().timeZone;
+  events.push({ id: "ev1", calendarIds: { c1: true }, "@type": "Event", uid: "ev1", title: "Standup", start: local(d(0, 9)), timeZone: tz, duration: "PT30M", recurrenceRule: { "@type": "RecurrenceRule", frequency: "weekly", byDay: [{ day: "mo" }, { day: "tu" }, { day: "we" }, { day: "th" }, { day: "fr" }] }, showWithoutTime: false, status: "confirmed", freeBusyStatus: "busy", privacy: "public" });
+  events.push({ id: "ev2", calendarIds: { c2: true }, "@type": "Event", uid: "ev2", title: "Design review", start: local(d(1, 14)), timeZone: tz, duration: "PT1H30M", showWithoutTime: false, locations: { l: { "@type": "Location", name: "Room 2" } }, participants: { me: { "@type": "Participant", name: "Demo User", calendarAddress: `mailto:${USER}`, roles: { owner: true, attendee: true }, participationStatus: "accepted" }, p2: { "@type": "Participant", name: "Ada Lovelace", calendarAddress: "mailto:[email protected]", roles: { attendee: true, required: true }, participationStatus: "needs-action", expectReply: true } }, organizerCalendarAddress: `mailto:${USER}` });
+  events.push({ id: "ev3", calendarIds: { c1: true }, "@type": "Event", uid: "ev3", title: "Conference", start: local(d(3, 0)).slice(0, 10) + "T00:00:00", duration: "P2D", showWithoutTime: true, timeZone: null });
+  /*
+   * One event in a zone that is not the reader's, because every other fixture
+   * here uses the machine's own and so cannot tell a correct conversion from
+   * no conversion at all. Dragging this one is what proves a move keeps the
+   * time the event says it happens at.
+   */
+  events.push({ id: "ev9", calendarIds: { c1: true }, "@type": "Event", uid: "ev9", title: "Tokyo sync", start: local(d(2, 15)), timeZone: "Asia/Tokyo", duration: "PT1H", showWithoutTime: false, color: "#7c3aed" });
+  events.push({ id: "ev4", calendarIds: { c1: true }, "@type": "Event", uid: "ev4", title: "Lunch with Grace", start: local(d(2, 12)), timeZone: tz, duration: "PT1H", showWithoutTime: false, color: "#db2777" });
+  // Two in the shared account, so a colleague's calendar has something in it.
+  sharedEvents.push({ id: "sv1", calendarIds: { c9: true }, "@type": "Event", uid: "sv1", title: "Grace: release planning", start: local(d(1, 10)), timeZone: tz, duration: "PT1H", showWithoutTime: false, status: "confirmed", freeBusyStatus: "busy", privacy: "public" });
+  sharedEvents.push({ id: "sv2", calendarIds: { c9: true }, "@type": "Event", uid: "sv2", title: "Grace: on leave", start: local(d(4, 0)).slice(0, 10) + "T00:00:00", duration: "P1D", showWithoutTime: true, timeZone: null });
+}
+export const participantIdentities: Obj[] = [{ id: "pi1", name: "Demo User", calendarAddress: `mailto:${USER}`, sendTo: { imip: `mailto:${USER}` }, isDefault: true }];
+export const abRights = (write = true) => ({ mayRead: true, mayWrite: write, mayShare: write, mayDelete: write });
+export const addressBooks: Obj[] = [{ id: "ab1", name: "Personal", description: null, sortOrder: 0, isDefault: true, isSubscribed: true, shareWith: {}, myRights: abRights() }];
+/* A book in the shared account, so "Shared with me" and addressing a message
+   from somebody else's contacts can be exercised at all. Read-only, which is
+   what a share usually is. */
+export const sharedAddressBooks: Obj[] = [{ id: "ab9", name: "Team contacts", description: null, sortOrder: 0, isDefault: true, isSubscribed: false, shareWith: {}, myRights: abRights(false) }];
+export const sharedCards: Obj[] = [
+  { id: "sc1", addressBookIds: { ab9: true }, name: { full: "Katherine Johnson" }, emails: { e1: { address: "[email protected]", contexts: {} } }, phones: {}, organizations: {}, nicknames: {}, addresses: {}, notes: {}, updated: new Date().toISOString() },
+  { id: "sc2", addressBookIds: { ab9: true }, name: { full: "Dorothy Vaughan" }, emails: { e1: { address: "[email protected]", contexts: {} } }, phones: {}, organizations: {}, nicknames: {}, addresses: {}, notes: {}, updated: new Date().toISOString() },
+];
+/**
+ * One sort property, as Email/query defines them. `hasKeyword` sorts a
+ * boolean, and false comes before true -- which is what makes "unread first"
+ * an *ascending* sort on $seen.
+ */
+export function compareBy(x: Obj, y: Obj, property: string, keyword?: string): number {
+  const addr = (v: unknown) => String(((v as Obj[] | undefined)?.[0] as Obj | undefined)?.email ?? "");
+  switch (property) {
+    case "receivedAt": return String(x.receivedAt).localeCompare(String(y.receivedAt));
+    case "sentAt": return String(x.sentAt ?? x.receivedAt).localeCompare(String(y.sentAt ?? y.receivedAt));
+    case "size": return Number(x.size ?? 0) - Number(y.size ?? 0);
+    case "subject": return String(x.subject ?? "").localeCompare(String(y.subject ?? ""));
+    case "from": return addr(x.from).localeCompare(addr(y.from));
+    case "to": return addr(x.to).localeCompare(addr(y.to));
+    case "hasKeyword": {
+      const has = (e: Obj) => (keyword && (e.keywords as Obj | undefined)?.[keyword] ? 1 : 0);
+      return has(x) - has(y);
+    }
+    default: return 0;
+  }
+}
+
+/** A server that does not implement sorting on keywords, so the fallback can be developed against. */
+export const NO_KEYWORD_SORT = process.env.MOCK_NO_KEYWORD_SORT === "1";
+
+/** The floor Stalwart puts under a requested EventSource ping interval. */
+export const PING_FLOOR_SECONDS = 30;
+
+/*
+ * An account that may not send calendar invitations.
+ *
+ * 0.16.21 rejects a `CalendarEvent/set` that asks for scheduling messages when
+ * the account lacks the `calendarSchedulingSend` permission, rather than
+ * accepting the write and quietly sending nothing. **Confirmed live on 0.16.21
+ * (2026-09-06)** against an account holding a role with that permission
+ * disabled: `sendSchedulingMessages: true` came back `notCreated` with
+ * `forbidden` and the text below, while the identical request with the flag
+ * false was created normally. Set MOCK_NO_SCHEDULING_SEND=1 to develop against
+ * that account.
+ */
+export const NO_SCHEDULING_SEND = process.env.MOCK_NO_SCHEDULING_SEND === "1";
+export const SCHEDULING_FORBIDDEN = "This account is not allowed to send calendar scheduling messages.";
+
+export const booksFor = (accountId: unknown): Obj[] => (accountId === SHARED_ACCOUNT ? sharedAddressBooks : addressBooks);
+/** One per contact, by index; a gap means that card has no birthday. */
+export const BIRTHDAYS: Array<{ year?: number; month: number; day: number } | null> = [
+  { year: 1815, month: 12, day: 10 },
+  { month: 6, day: 9 }, // no year: the common case
+  { year: 1912, month: 6, day: 23 },
+  null,
+  { year: 2000, month: 2, day: 29 }, // lands on the 28th in a non-leap year
+  { year: 1918, month: 8, day: 26 },
+];
+
+export const cards: Obj[] = people.slice(0, 6).map((p, i) => {
+  const [given, surname] = p[0]!.split(" ");
+  return { id: `cc${i}`, addressBookIds: { ab1: true }, "@type": "Card", version: "1.0", uid: `uid-cc${i}`, kind: "individual", name: { components: [{ kind: "given", value: given }, { kind: "surname", value: surname ?? "" }], isOrdered: true }, emails: { e1: { address: p[1], contexts: { work: true } } }, phones: i % 2 ? { p1: { number: `+1 555 010${i}`, features: { mobile: true } } } : undefined, organizations: i % 3 ? { o1: { name: "Example Corp" } } : undefined,
+    /*
+     * Birthdays on most but not all of them, and one with no year, because a
+     * card that records only a day and month is the common case rather than
+     * the exceptional one.
+     */
+    anniversaries: BIRTHDAYS[i] ? { a1: { "@type": "Anniversary", kind: "birth", date: { "@type": "PartialDate", ...BIRTHDAYS[i] } } } : undefined };
+});
+export const principals: Obj[] = people.slice(0, 5).map((p, i) => ({ id: `pr${i}`, type: "individual", name: p[0], description: null, email: p[1], timeZone: "UTC" }));
+export const fileNodes: Obj[] = [
+  { id: "f1", parentId: null, nodeType: "directory", blobId: null, size: null, name: "Documents", type: null, created: new Date().toISOString(), modified: new Date().toISOString(), myRights: fr(), shareWith: {}, role: "documents" },
+  { id: "f2", parentId: "f1", nodeType: "file", blobId: putBlob("hello world", "text/plain"), size: 11, name: "notes.txt", type: "text/plain", created: new Date().toISOString(), modified: new Date().toISOString(), myRights: fr(), shareWith: {} },
+  { id: "f3", parentId: null, nodeType: "file", blobId: putBlob("%PDF-1.4 mock", "application/pdf"), size: 14, name: "report.pdf", type: "application/pdf", created: new Date().toISOString(), modified: new Date().toISOString(), myRights: fr(), shareWith: {} },
+];
+
+/* What the shared account holds. Its own nodes, so opening the share in Files
+   shows something different from the reader's own folders rather than the same
+   list under another name. */
+export const sharedFileNodes: Obj[] = [
+  { id: "s1", parentId: null, nodeType: "directory", blobId: null, size: null, name: "Team plans", type: null, created: new Date().toISOString(), modified: new Date().toISOString(), myRights: fr(), shareWith: {} },
+  { id: "s2", parentId: "s1", nodeType: "file", blobId: putBlob("shared notes", "text/plain"), size: 12, name: "roadmap.txt", type: "text/plain", created: new Date().toISOString(), modified: new Date().toISOString(), myRights: fr(), shareWith: {} },
+];
+/** The node list an account owns. */
+export const nodesFor = (accountId: unknown): Obj[] => (accountId === SHARED_ACCOUNT ? sharedFileNodes : fileNodes);
+
+export function fr() {
+  return { mayRead: true, mayAddChildren: true, mayRename: true, mayDelete: true, mayModifyContent: true, mayShare: true };
+}
+
+export function recount() {
+  for (const m of mailboxes) {
+    const inBox = emails.filter((e) => (e.mailboxIds as Obj)[m.id as string]);
+    m.totalEmails = inBox.length;
+    m.unreadEmails = inBox.filter((e) => !(e.keywords as Obj).$seen).length;
+    const threads = new Set(inBox.map((e) => e.threadId));
+    m.totalThreads = threads.size;
+    m.unreadThreads = new Set(inBox.filter((e) => !(e.keywords as Obj).$seen).map((e) => e.threadId)).size;
+  }
+}
+recount();
+
@@ -0,0 +1,442 @@
+import { randomUUID } from "node:crypto";
+import { eventGetView, expandOccurrences, occurrenceAt, occurrenceView, parseSyntheticId, splitOccurrencePatch, syntheticId, type Occurrence } from "./recurrence.js";
+import { holdUntilOf, undoStatusOf } from "./futurerelease.js";
+import { createDirectory, mockRole } from "./directory.js";
+import { ACCOUNT, MOCK_LOCALE, Obj, USER, account, nextState, state } from "./config.js";
+import { NO_SCHEDULING_SEND, SCHEDULING_FORBIDDEN, blobs, events, mailboxes } from "./data.js";
+
+/* ---------- helpers ---------- */
+export function pick(o: Obj, props?: string[] | null): Obj {
+  if (!props) return o;
+  const out: Obj = { id: o.id };
+  for (const p of props) if (p in o) out[p] = o[p];
+  else if (p.startsWith("header:")) out[p] = null;
+  return out;
+}
+export function resolveRefs(args: Obj, responses: [string, Obj, string][], creations: Record<string, string>): Obj {
+  const out: Obj = {};
+  for (const [k, v] of Object.entries(args)) {
+    if (k.startsWith("#")) {
+      const r = v as { resultOf: string; name: string; path: string };
+      const resp = responses.find((x) => x[2] === r.resultOf && x[0] === r.name);
+      out[k.slice(1)] = resp ? jsonPointer(resp[1], r.path) : [];
+    } else out[k] = resolveCreationIds(v, creations, k);
+  }
+  return out;
+}
+
+/**
+ * Creation references (RFC 8620 5.3): a `#creationId` anywhere a real id would
+ * go, pointing at something created earlier in the same request. Sending a
+ * message uses one -- `EmailSubmission/set` names the email as `#m` -- so
+ * without this the mock quietly declines to create any submission at all.
+ *
+ * `onSuccessUpdateEmail` is left alone: its keys are creation ids by design and
+ * the method that receives them resolves them itself.
+ */
+export function resolveCreationIds(value: unknown, creations: Record<string, string>, key?: string): unknown {
+  if (key === "onSuccessUpdateEmail") return value;
+  if (typeof value === "string") {
+    return value.startsWith("#") && creations[value.slice(1)] ? creations[value.slice(1)]! : value;
+  }
+  if (Array.isArray(value)) return value.map((v) => resolveCreationIds(v, creations));
+  if (value && typeof value === "object") {
+    const out: Obj = {};
+    for (const [k, v] of Object.entries(value as Obj)) {
+      const nk = k.startsWith("#") && creations[k.slice(1)] ? creations[k.slice(1)]! : k;
+      out[nk] = resolveCreationIds(v, creations, k);
+    }
+    return out;
+  }
+  return value;
+}
+export function jsonPointer(obj: unknown, path: string): unknown {
+  const parts = path.split("/").filter(Boolean);
+  let cur: unknown = obj;
+  for (let i = 0; i < parts.length; i++) {
+    const p = parts[i]!;
+    if (p === "*") {
+      const rest = parts.slice(i + 1).join("/");
+      const arr = (cur as unknown[]).flatMap((x) => { const v = jsonPointer(x, "/" + rest); return Array.isArray(v) ? v : [v]; });
+      return arr;
+    }
+    cur = (cur as Obj)?.[p];
+  }
+  return cur;
+}
+export function matchFilter(e: Obj, f: Obj | undefined): boolean {
+  if (!f) return true;
+  if (f.operator) {
+    const conds = (f.conditions as Obj[]).map((c) => matchFilter(e, c));
+    return f.operator === "AND" ? conds.every(Boolean) : f.operator === "OR" ? conds.some(Boolean) : !conds.some(Boolean);
+  }
+  const kw = e.keywords as Obj;
+  if (f.inMailbox && !(e.mailboxIds as Obj)[f.inMailbox as string]) return false;
+  if (f.hasKeyword && !kw[f.hasKeyword as string]) return false;
+  if (f.notKeyword && kw[f.notKeyword as string]) return false;
+  if (f.hasAttachment !== undefined && Boolean(e.hasAttachment) !== f.hasAttachment) return false;
+  const hay = `${e.subject} ${JSON.stringify(e.from)} ${JSON.stringify(e.to)} ${e.preview}`.toLowerCase();
+  for (const k of ["text", "subject", "from", "to", "body"]) if (f[k] && !hay.includes(String(f[k]).toLowerCase())) return false;
+  if (f.before && String(e.receivedAt) >= String(f.before)) return false;
+  if (f.after && String(e.receivedAt) < String(f.after)) return false;
+  if (f.minSize && Number(e.size) < Number(f.minSize)) return false;
+  if (f.maxSize && Number(e.size) > Number(f.maxSize)) return false;
+  return true;
+}
+export function applyPatch(obj: Obj, patch: Obj) {
+  for (const [k, v] of Object.entries(patch)) {
+    if (k.includes("/")) {
+      const [root, ...rest] = k.split("/");
+      const key = rest.join("/");
+      const target = (obj[root!] as Obj) ?? {};
+      if (v === null) delete target[key];
+      else target[key] = v;
+      obj[root!] = target;
+    } else obj[k] = v;
+  }
+}
+
+/* ---------- method handlers ---------- */
+export type Handler = (args: Obj) => Obj | [string, Obj][];
+/** A method-level failure, surfaced as ["error", {type, description}, id]. */
+export class MethodError extends Error {
+  constructor(
+    public readonly type: string,
+    description?: string,
+  ) {
+    super(description ?? type);
+  }
+}
+
+export const MAX_OBJECTS = 500;
+
+/**
+ * Stalwart refuses a whole method call that carries more objects than it will
+ * process at once - it does not quietly handle the first 500. Enforce the same
+ * ceiling the session advertises, so an unbatched client fails here too.
+ */
+export function enforceLimits(name: string, args: Obj): void {
+  const tooLarge = () => {
+    throw new MethodError("requestTooLarge", "The number of ids requested by the client exceeds the maximum number the server is willing to process in a single method call.");
+  };
+  if (name.endsWith("/get")) {
+    const ids = args.ids as unknown[] | null | undefined;
+    if (Array.isArray(ids) && ids.length > MAX_OBJECTS) tooLarge();
+  }
+  if (name.endsWith("/set")) {
+    const n =
+      Object.keys((args.create as Obj) ?? {}).length +
+      Object.keys((args.update as Obj) ?? {}).length +
+      ((args.destroy as unknown[] | undefined)?.length ?? 0);
+    if (n > MAX_OBJECTS) tooLarge();
+  }
+}
+
+export const setResp = (extra: Obj = {}): Obj => ({ accountId: ACCOUNT, oldState: "1", newState: nextState(), created: {}, updated: {}, destroyed: [], ...extra });
+
+/*
+ * `Mailbox/get` does not return `shareWith` unless a client asks for it by
+ * name: a `/get` with no `properties` comes back without the field at all.
+ * Confirmed on 0.16.19 (2026-08-27) against a mailbox that really was shared.
+ * The mock handing it over unasked meant a client that never asked still saw
+ * every share, and the one place that did not -- the real server -- showed
+ * nothing shared at all.
+ *
+ * Calendars and address books used to behave the same way and no longer do.
+ * 0.16.21 fixed `Calendar/get` and `AddressBook/get` to return every property
+ * when `properties` is omitted or null, `shareWith` included. **Confirmed live
+ * on 0.16.21 (2026-09-06):** both come back with the full set, while
+ * `Mailbox/get` on the same server still omits it — so this stays, and it
+ * stays applied to mailboxes alone.
+ */
+export function hideShareWithUnlessAsked(a: Obj, res: { list: Obj[] }): { list: Obj[] } {
+  if (a.properties) return res;
+  return { ...res, list: res.list.map(({ shareWith: _drop, ...rest }) => rest) };
+}
+
+export function genericGet(list: Obj[]) {
+  return (a: Obj) => {
+    const ids = a.ids as string[] | null | undefined;
+    const found = ids ? ids.map((id) => list.find((x) => x.id === id)).filter(Boolean) as Obj[] : list;
+    return { accountId: ACCOUNT, state: String(state.n), list: found.map((x) => pick(x, a.properties as string[] | null)), notFound: ids ? ids.filter((id) => !list.some((x) => x.id === id)) : [] };
+  };
+}
+/**
+ * An id, as either a stored event or one occurrence of one.
+ *
+ * A synthetic id whose base is gone, or whose date the rule no longer
+ * generates (excluded, or past a `count`), resolves to nothing — `notFound`,
+ * the way the server answers for an occurrence that is not there any more.
+ */
+export function resolveEvent(list: Obj[], id: string): { base: Obj; occ?: Occurrence } | null {
+  const direct = list.find((x) => x.id === id);
+  if (direct) return { base: direct };
+  const parsed = parseSyntheticId(id);
+  if (!parsed) return null;
+  const base = list.find((x) => x.id === parsed.baseId);
+  if (!base) return null;
+  const occ = occurrenceAt(base, parsed.recurrenceId);
+  return occ ? { base, occ } : null;
+}
+
+/** Thrown from an onCreate hook to refuse a create the way a real server would. */
+export class SetError extends Error {
+  constructor(readonly type: string, readonly description: string, readonly properties?: string[]) { super(description); }
+  toJSON(): Obj { return { type: this.type, description: this.description, ...(this.properties ? { properties: this.properties } : {}) }; }
+}
+
+export function genericSet(list: Obj[], prefix: string, onCreate?: (o: Obj) => void) {
+  return (a: Obj) => {
+    const created: Obj = {};
+    const updated: Obj = {};
+    const destroyed: string[] = [];
+    const notCreated: Obj = {};
+    for (const [cid, obj] of Object.entries((a.create as Obj) ?? {})) {
+      const id = `${prefix}${randomUUID().slice(0, 6)}`;
+      const o = { ...(obj as Obj), id };
+      try {
+        onCreate?.(o);
+      } catch (err) {
+        if (!(err instanceof SetError)) throw err;
+        notCreated[cid] = err.toJSON();
+        continue;
+      }
+      list.push(o);
+      created[cid] = { id };
+    }
+    for (const [id, patch] of Object.entries((a.update as Obj) ?? {})) {
+      const o = list.find((x) => x.id === id);
+      if (o) { applyPatch(o, patch as Obj); updated[id] = null; }
+    }
+    for (const id of (a.destroy as string[]) ?? []) {
+      const i = list.findIndex((x) => x.id === id);
+      if (i >= 0) { list.splice(i, 1); destroyed.push(id); }
+    }
+    return setResp({ created, updated, destroyed, ...(Object.keys(notCreated).length ? { notCreated } : {}) });
+  };
+}
+
+/* ---------- calendar events ---------- */
+
+/**
+ * `CalendarEvent/set`, including the synthetic-id handling 0.16.20 added.
+ *
+ * An update or destroy aimed at an occurrence does not touch the series: it
+ * writes a `recurrenceOverrides` entry keyed by that date, exactly as Stalwart
+ * does — `{ excluded: true }` for a destroy, the patch merged in for an update.
+ *
+ * The refusals are the point of reproducing this at all:
+ *
+ * - a base event and one of its instances in the same request is refused, both
+ *   ids at once, because the server cannot apply them in a defined order;
+ * - the same id twice is "Duplicate event id.";
+ * - the ten event-level properties are refused with `invalidProperties`;
+ * - and the twelve inherited ones are dropped in silence, with the response
+ *   still saying the update succeeded. A mock that applied them would let a
+ *   client that sends them look correct everywhere except a real server.
+ */
+/**
+ * Enough of an iCalendar reader to stand in for Stalwart's.
+ *
+ * It reads per VEVENT rather than across the whole file, because a file is the
+ * case an emailed invitation never was: an export carries a year of them, and a
+ * regex over the whole text would find the first DTSTART and call that the
+ * answer. One event still comes back as a bare object, the shape this returned
+ * when an invitation was all it had to handle.
+ *
+ * The synthetic organizer and attendee only go on events that arrived with a
+ * METHOD. Those are scheduling messages, which is what the invitation fixtures
+ * are; a plain export is not addressed to anyone, and inventing participants
+ * for it would make imported events look like invitations nobody sent.
+ */
+export function calendarEventParse(a: Obj) {
+  const parsed: Obj = {};
+  const notParsable: string[] = [];
+  for (const b of a.blobIds as string[]) {
+    const blob = blobs.get(b);
+    if (!blob) { notParsable.push(b); continue; }
+    const text = blob.data.toString();
+    const field = (src: string, k: string) => new RegExp(`^${k}[^:\r\n]*:(.*)$`, "m").exec(src)?.[1]?.trim();
+    const method = field(text, "METHOD");
+    const bodies = text.match(/BEGIN:VEVENT[\s\S]*?END:VEVENT/g) ?? [];
+    const events = bodies.map((body) => {
+      const g = (k: string) => field(body, k);
+      const ds = g("DTSTART") ?? "20260101T000000Z";
+      const de = g("DTEND") ?? ds;
+      const toLocal = (s: string) => `${s.slice(0, 4)}-${s.slice(4, 6)}-${s.slice(6, 8)}T${s.slice(9, 11)}:${s.slice(11, 13)}:00`;
+      const start = new Date(`${toLocal(ds)}Z`);
+      const end = new Date(`${toLocal(de)}Z`);
+      return {
+        "@type": "Event",
+        uid: g("UID"),
+        title: g("SUMMARY"),
+        start: toLocal(ds),
+        timeZone: "Etc/UTC",
+        duration: `PT${Math.round((end.getTime() - start.getTime()) / 60000)}M`,
+        method,
+        locations: g("LOCATION") ? { l: { name: g("LOCATION") } } : undefined,
+        participants: method
+          ? {
+              org: { name: "Ada Lovelace", calendarAddress: "mailto:[email protected]", roles: { owner: true } },
+              me: { name: "Demo User", calendarAddress: `mailto:${USER}`, roles: { attendee: true, required: true }, participationStatus: "needs-action" },
+            }
+          : undefined,
+      };
+    });
+    if (!events.length) { notParsable.push(b); continue; }
+    parsed[b] = events.length === 1 ? events[0] : events;
+  }
+  return { accountId: ACCOUNT, parsed, notParsable };
+}
+
+export function calendarEventSet(a: Obj) {
+  const created: Obj = {};
+  const updated: Obj = {};
+  const destroyed: string[] = [];
+  const notCreated: Obj = {};
+  const notUpdated: Obj = {};
+  const notDestroyed: Obj = {};
+
+  /*
+   * An account that may not send invitations refuses the whole request the
+   * moment it asks for them, and refuses it per object rather than as a method
+   * error. Confirmed live on 0.16.21 for all three of create, update and
+   * destroy; the same requests with the flag absent or false went through.
+   * The flag alone decides it — the server does not first check whether the
+   * event has anyone to notify.
+   */
+  if (NO_SCHEDULING_SEND && a.sendSchedulingMessages === true) {
+    const denied = () => new SetError("forbidden", SCHEDULING_FORBIDDEN).toJSON();
+    for (const cid of Object.keys((a.create as Obj) ?? {})) notCreated[cid] = denied();
+    for (const id of Object.keys((a.update as Obj) ?? {})) notUpdated[id] = denied();
+    for (const id of ((a.destroy as string[]) ?? [])) notDestroyed[id] = denied();
+    return setResp({
+      created, updated, destroyed,
+      ...(Object.keys(notCreated).length ? { notCreated } : {}),
+      ...(Object.keys(notUpdated).length ? { notUpdated } : {}),
+      ...(Object.keys(notDestroyed).length ? { notDestroyed } : {}),
+    });
+  }
+
+  for (const [cid, obj] of Object.entries((a.create as Obj) ?? {})) {
+    const o: Obj = { ...(obj as Obj), id: `ev${randomUUID().slice(0, 6)}` };
+    // Stalwart 0.16 rejects the RFC 8984 array outright and silently discards
+    // participants addressed the RFC 8984 way. The mock did neither, which is
+    // how #26 and #30 reached a live server unnoticed — so it does both.
+    if (o.recurrenceRules) { notCreated[cid] = new SetError("invalidProperties", "Invalid property.", ["recurrenceRules"]).toJSON(); continue; }
+    const parts = o.participants as Record<string, Obj> | undefined;
+    if (parts && Object.values(parts).some((p) => !p.calendarAddress)) delete o.participants;
+    if (o.replyTo && !o.organizerCalendarAddress) delete o.replyTo;
+    o.uid = o.uid ?? randomUUID();
+    events.push(o);
+    created[cid] = { id: o.id };
+  }
+
+  const updates = Object.entries((a.update as Obj) ?? {});
+  const destroys = ((a.destroy as string[]) ?? []).slice();
+  const seen = new Set<string>();
+
+  /* A base and one of its instances cannot be settled in the same request. */
+  const baseOf = (id: string): string | null => {
+    const r = resolveEvent(events, id);
+    return r ? (r.base.id as string) : null;
+    };
+  const touched = new Map<string, { base: string[]; instance: string[] }>();
+  for (const id of [...updates.map(([id]) => id), ...destroys]) {
+    const b = baseOf(id);
+    if (!b) continue;
+    const entry = touched.get(b) ?? { base: [], instance: [] };
+    (parseSyntheticId(id) ? entry.instance : entry.base).push(id);
+    touched.set(b, entry);
+  }
+  const conflicted = new Set<string>();
+  for (const [, e] of touched) {
+    if (e.base.length && e.instance.length) for (const id of [...e.base, ...e.instance]) conflicted.add(id);
+  }
+  const conflict = () => new SetError("invalidProperties", "A base event and its instances cannot be modified in the same request.", ["id"]).toJSON();
+
+  for (const [id, patch] of updates) {
+    if (conflicted.has(id)) { notUpdated[id] = conflict(); continue; }
+    if (seen.has(id)) { notUpdated[id] = new SetError("invalidProperties", "Duplicate event id.", ["id"]).toJSON(); continue; }
+    seen.add(id);
+    const resolved = resolveEvent(events, id);
+    if (!resolved) { notUpdated[id] = { type: "notFound" }; continue; }
+    if (!resolved.occ) { applyPatch(resolved.base, patch as Obj); updated[id] = null; continue; }
+    const { rejected, applied } = splitOccurrencePatch(patch as Obj);
+    if (rejected) { notUpdated[id] = new SetError("invalidProperties", "This property cannot be modified on a single occurrence.", [rejected]).toJSON(); continue; }
+    writeOverride(resolved.base, resolved.occ, applied);
+    updated[id] = null;
+  }
+
+  for (const id of destroys) {
+    if (conflicted.has(id)) { notDestroyed[id] = conflict(); continue; }
+    const resolved = resolveEvent(events, id);
+    if (!resolved) { notDestroyed[id] = { type: "notFound" }; continue; }
+    if (resolved.occ) {
+      // One date off a series, which is an override rather than a deletion.
+      writeOverride(resolved.base, resolved.occ, { excluded: true }, true);
+      destroyed.push(id);
+      continue;
+    }
+    const i = events.findIndex((x) => x.id === id);
+    if (i >= 0) { events.splice(i, 1); destroyed.push(id); }
+  }
+
+  return setResp({
+    created, updated, destroyed,
+    ...(Object.keys(notCreated).length ? { notCreated } : {}),
+    ...(Object.keys(notUpdated).length ? { notUpdated } : {}),
+    ...(Object.keys(notDestroyed).length ? { notDestroyed } : {}),
+  });
+}
+
+/**
+ * Merge a patch into the override for one date.
+ *
+ * Stalwart fills `start` and `duration` in when the patch leaves them out, so
+ * an override always carries its own timing; the mock does the same, or a
+ * client could depend on inheriting them and be right only here.
+ */
+export function writeOverride(base: Obj, occ: Occurrence, patch: Obj, replace = false) {
+  const overrides = (base.recurrenceOverrides as Record<string, Obj> | undefined) ?? {};
+  const existing = replace ? {} : (overrides[occ.recurrenceId] ?? {});
+  const next: Obj = { ...existing };
+  if (!replace) {
+    if (!("start" in next)) next.start = occ.start;
+    if (!("duration" in next) && base.duration) next.duration = base.duration;
+  }
+  applyPatch(next, patch);
+  overrides[occ.recurrenceId] = next;
+  base.recurrenceOverrides = overrides;
+}
+
+/* ---------- submissions ---------- */
+/**
+ * Held messages, the way Stalwart models them: `sendAt` is derived from the
+ * envelope's FUTURERELEASE parameter rather than set by the client, and
+ * `undoStatus` reports whether the message is still in the queue.
+ */
+export const submissions: Obj[] = [];
+
+export function submissionView(sub: Obj): Obj {
+  return { ...sub, undoStatus: undoStatusOf(sub, Date.now()) };
+}
+
+export function matchSubmissionFilter(sub: Obj, f: Obj | undefined): boolean {
+  if (!f) return true;
+  if (f.undoStatus && undoStatusOf(sub, Date.now()) !== f.undoStatus) return false;
+  if (Array.isArray(f.emailIds) && !(f.emailIds as string[]).includes(sub.emailId as string)) return false;
+  if (Array.isArray(f.identityIds) && !(f.identityIds as string[]).includes(sub.identityId as string)) return false;
+  return true;
+}
+
+/** Who the demo user is, for administration. See mock/directory.ts. */
+export const directory = createDirectory({
+  accountId: ACCOUNT,
+  user: USER,
+  locale: MOCK_LOCALE,
+  role: mockRole(process.env.MOCK_ROLE),
+  metricsOff: process.env.MOCK_METRICS === "off",
+  fail: (type, description) => new MethodError(type, description),
+});
+
@@ -0,0 +1,36 @@
+import type { ServerResponse } from "node:http";
+import { ACCOUNT, state } from "./config.js";
+
+/*
+ * The server-sent-events fan-out and the Email/changes ring buffer.
+ *
+ * Separate from index.ts because the JMAP handlers raise these events and
+ * index.ts imports the handlers -- leaving them in index.ts makes that a
+ * cycle. Separate from data.ts because a live HTTP response is not fixture
+ * data.
+ */
+export const sseClients = new Set<ServerResponse>();
+/** What changed and when, so `Email/changes` can answer honestly. */
+export const emailChanges: Array<{ state: number; created: string[]; updated: string[]; destroyed: string[] }> = [];
+export function recordEmailChange(change: { created?: string[]; updated?: string[]; destroyed?: string[] }) {
+  emailChanges.push({ state: state.n, created: change.created ?? [], updated: change.updated ?? [], destroyed: change.destroyed ?? [] });
+  // A window is plenty; the client refetches from scratch if it falls behind.
+  if (emailChanges.length > 200) emailChanges.splice(0, emailChanges.length - 200);
+}
+
+/** The same for contact cards, so `ContactCard/changes` can answer too. */
+export const cardChanges: Array<{ state: number; created: string[]; updated: string[]; destroyed: string[] }> = [];
+/** Changes at or below this state have been dropped from the log, so a client that far behind cannot be answered. */
+export const cardLog = { floor: 0 };
+export function recordCardChange(change: { created?: string[]; updated?: string[]; destroyed?: string[] }) {
+  cardChanges.push({ state: state.n, created: change.created ?? [], updated: change.updated ?? [], destroyed: change.destroyed ?? [] });
+  if (cardChanges.length > 200) {
+    const dropped = cardChanges.splice(0, cardChanges.length - 200);
+    cardLog.floor = dropped[dropped.length - 1]!.state;
+  }
+}
+
+export function broadcast(types: string[]) {
+  const payload = `event: state\ndata: ${JSON.stringify({ "@type": "StateChange", changed: { [ACCOUNT]: Object.fromEntries(types.map((t) => [t, String(state.n)])) } })}\n\n`;
+  for (const c of sseClients) c.write(payload);
+}
@@ -0,0 +1,516 @@
+import { checkOtp } from "./auth.js";
+import { cardChanges, cardLog, emailChanges, recordCardChange, recordEmailChange, broadcast } from "./events.js";
+import { randomUUID } from "node:crypto";
+import { eventGetView, expandOccurrences, occurrenceAt, occurrenceView, parseSyntheticId, splitOccurrencePatch, syntheticId, type Occurrence } from "./recurrence.js";
+import { holdUntilOf, undoStatusOf } from "./futurerelease.js";
+import { ACCOUNT, MASKED, MAX_DELAYED_SEND, MOCK_LOCALE, NO_FUTURE_RELEASE, Obj, PUSH_TTL_MS, SHARED_ACCOUNT, account, nextState, state } from "./config.js";
+import { NO_KEYWORD_SORT, abRights, blobs, booksFor, calendarsFor, cards, compareBy, emails, eventsFor, fileNodes, fr, identities, mailboxes, mb, nodesFor, participantIdentities, principals, pushSubscriptions, putBlob, recount, rightsCal, seq, sharedCards, sieveScripts, vacationBox } from "./data.js";
+import { Handler, MethodError, applyPatch, calendarEventParse, calendarEventSet, directory, genericGet, genericSet, hideShareWithUnlessAsked, matchFilter, matchSubmissionFilter, pick, resolveEvent, setResp, submissionView, submissions } from "./engine.js";
+
+/** Stalwart's limit per account (0.16.22). */
+const MAX_PUSH_SUBSCRIPTIONS = 15;
+/** What an empty or missing `types` list is taken to mean: everything. */
+const ALL_PUSH_TYPES = ["Email", "EmailDelivery", "Mailbox", "Thread", "Identity", "EmailSubmission", "VacationResponse", "CalendarEvent", "Calendar", "ContactCard", "AddressBook", "FileNode", "Quota", "SieveScript", "PushSubscription"];
+
+export const handlers: Record<string, Handler> = {
+  // 0.16 exposes the account locale here, under a permission ordinary users
+  // actually have (unlike x:Account below, which needs sysAccountGet).
+  "x:AccountSettings/get": (a) => {
+    const ids = (a.ids as string[] | null) ?? ["singleton"];
+    const list = ids.filter((id) => id === "singleton").map((id) => ({ id, locale: MOCK_LOCALE, timeZone: null, description: null }));
+    return { accountId: ACCOUNT, state: String(state.n), list: list.map((x) => pick(x, a.properties as string[] | null)), notFound: ids.filter((id) => id !== "singleton") };
+  },
+  // Stalwart's directory registry: accounts, domains and roles, behind the
+  // same permissions as the real thing. The locale fallback reads x:Account
+  // too, and is refused here exactly when a real server would refuse it.
+  ...directory.handlers,
+  "Mailbox/get": (a) => hideShareWithUnlessAsked(a, genericGet(mailboxes)(a) as { list: Obj[] }) as never,
+  "Mailbox/set": (a) => { const r = genericSet(mailboxes, "m", (o) => Object.assign(o, { ...mb(o.id as string, o.name as string, null, (o.parentId as string) ?? null), ...o }))(a); recount(); return r; },
+  "Mailbox/changes": () => ({ accountId: ACCOUNT, oldState: "1", newState: String(state.n), hasMoreChanges: false, created: [], updated: [], destroyed: [] }),
+  "Email/query": (a) => {
+    let list = emails.filter((e) => matchFilter(e, a.filter as Obj));
+    /*
+     * Honor the sort rather than always answering newest-first. This used to
+     * ignore it entirely, which reproduced a server that silently returns a
+     * different order from the one asked for -- the one shape of wrongness a
+     * client cannot detect.
+     */
+    const sort = (a.sort as Obj[] | undefined) ?? [{ property: "receivedAt", isAscending: false }];
+    if (NO_KEYWORD_SORT && sort.some((c) => String(c.property) === "hasKeyword")) {
+      // A method-level failure, the way a real server refuses an optional sort:
+      // the whole call fails rather than the sort being quietly dropped.
+      throw new MethodError("unsupportedSort", "Sorting on hasKeyword is not supported.");
+    }
+    list.sort((x, y) => {
+      for (const c of sort) {
+        const asc = c.isAscending !== false;
+        const cmp = compareBy(x, y, String(c.property), c.keyword as string | undefined);
+        if (cmp !== 0) return asc ? cmp : -cmp;
+      }
+      return 0;
+    });
+    if (a.collapseThreads) {
+      const seen = new Set<string>();
+      list = list.filter((e) => { const t = e.threadId as string; if (seen.has(t)) return false; seen.add(t); return true; });
+    }
+    const pos = Number(a.position ?? 0);
+    const limit = Number(a.limit ?? 50);
+    return { accountId: ACCOUNT, queryState: String(state.n), canCalculateChanges: false, position: pos, ids: list.slice(pos, pos + limit).map((e) => e.id), total: list.length, limit };
+  },
+  "Email/get": (a) => genericGet(emails)(a),
+  /*
+   * Real changes, not an empty answer.
+   *
+   * This used to return three empty arrays whatever had happened, so the
+   * client's whole reconciliation path -- `Email/changes`, then deciding what
+   * to do with what came back -- never ran against the mock. A bug living in
+   * that path could not be reproduced here at all, which is how one reached
+   * production and survived being "fixed" once (#100). The log below is what
+   * the real server can answer from.
+   */
+  "Email/changes": (a) => {
+    const since = Number(a.sinceState ?? 0);
+    const relevant = emailChanges.filter((c) => c.state > since);
+    const pick = (k: "created" | "updated" | "destroyed") => [...new Set(relevant.flatMap((c) => c[k]))];
+    return { accountId: ACCOUNT, oldState: String(a.sinceState ?? "1"), newState: String(state.n), hasMoreChanges: false, created: pick("created"), updated: pick("updated"), destroyed: pick("destroyed") };
+  },
+  "Email/set": (a) => {
+    const r = genericSet(emails, "e", (o) => {
+      const bv = (o.bodyValues as Record<string, { value: string }>) ?? {};
+      const walk = (p: Obj | undefined, acc: Obj[]) => { if (!p) return; if (p.partId && bv[p.partId as string]) acc.push({ ...p, blobId: putBlob(bv[p.partId as string]!.value, p.type as string), size: bv[p.partId as string]!.value.length }); (p.subParts as Obj[] | undefined)?.forEach((s) => walk(s, acc)); };
+      const parts: Obj[] = [];
+      walk(o.bodyStructure as Obj, parts);
+      o.textBody = parts.filter((p) => p.type === "text/plain");
+      o.htmlBody = parts.filter((p) => p.type === "text/html");
+      o.attachments = [];
+      const collect = (p: Obj | undefined) => { if (!p) return; if (p.blobId && !p.partId && p.type !== "multipart/mixed") (o.attachments as Obj[]).push({ ...p, size: p.size ?? 0 }); (p.subParts as Obj[] | undefined)?.forEach(collect); };
+      collect(o.bodyStructure as Obj);
+      o.hasAttachment = (o.attachments as Obj[]).length > 0;
+      o.threadId = o.inReplyTo ? (emails.find((e) => (e.messageId as string[] | null)?.[0] === (o.inReplyTo as string[])[0])?.threadId ?? `t${o.id}`) : `t${o.id}`;
+      o.receivedAt = new Date().toISOString().replace(/\.\d{3}Z$/, "Z");
+      o.size = 2000;
+      o.preview = (bv.text?.value ?? "").slice(0, 100);
+      o.messageId = [`${o.id}@mock`];
+      o.blobId = putBlob(`Subject: ${o.subject}\r\n\r\n${bv.text?.value ?? ""}`, "message/rfc822");
+    })(a);
+    recount();
+    nextState();
+    recordEmailChange({
+      created: Object.values((r.created ?? {}) as Record<string, { id: string }>).map((x) => x.id),
+      updated: Object.keys((a.update as Obj) ?? {}),
+      destroyed: (r.destroyed as string[] | undefined) ?? [],
+    });
+    /* A real server pushes a state change after a set, and the client acts on
+       it -- `Email/changes` runs and the store reconciles what came back. The
+       mock stayed silent, so that whole path never ran here and a bug living
+       in it could not be reproduced: marking a message read went round the
+       server and back on the live instance, and did nothing at all on the mock
+       (#100). Announced now, the way Stalwart does. */
+    broadcast(["Email", "Mailbox", "Thread"]);
+    return r;
+  },
+  "Email/import": (a) => { const created: Obj = {}; for (const [cid, spec] of Object.entries((a.emails as Obj) ?? {})) { const id = `e${seq.counter++}`; emails.push({ id, blobId: (spec as Obj).blobId, threadId: `t${id}`, mailboxIds: (spec as Obj).mailboxIds, keywords: (spec as Obj).keywords ?? {}, size: 100, receivedAt: new Date().toISOString(), subject: "(imported message)", from: [{ name: null, email: "import@example" }], to: null, preview: "", hasAttachment: false, textBody: [], htmlBody: [], attachments: [], bodyValues: {} }); created[cid] = { id }; } recount(); return setResp({ created }); },
+  "Thread/get": (a) => { const ids = a.ids as string[]; const list = ids.map((id) => ({ id, emailIds: emails.filter((e) => e.threadId === id).sort((x, y) => String(x.receivedAt).localeCompare(String(y.receivedAt))).map((e) => e.id) })).filter((t) => t.emailIds.length); return { accountId: ACCOUNT, state: String(state.n), list, notFound: ids.filter((id) => !list.some((t) => t.id === id)) }; },
+  // Stalwart 0.16 registry objects backing self-service credentials.
+  "x:AccountPassword/get": () => ({
+    accountId: ACCOUNT,
+    state: String(state.n),
+    list: [{ id: "singleton", otpAuth: { otpUrl: account.otpUrl ? MASKED : null, otpCode: null } }],
+    notFound: [],
+  }),
+  "x:AccountPassword/set": (a) => {
+    const patch = ((a.update as Obj) ?? {})["singleton"] as Obj | undefined;
+    if (!patch) return setResp({ updated: {} });
+    const current = patch.currentSecret as string | undefined;
+    const code = (patch["otpAuth/otpCode"] ?? (patch.otpAuth as Obj | undefined)?.otpCode) as string | undefined;
+    if (!current) {
+      return setResp({ notUpdated: { singleton: { type: "forbidden", description: "Current secret must be provided to change the password or OTP auth." } } });
+    }
+    if (current !== account.password) {
+      return setResp({ notUpdated: { singleton: { type: "forbidden", description: "Current secret is incorrect." } } });
+    }
+    if (account.otpUrl && !code) {
+      return setResp({ notUpdated: { singleton: { type: "forbidden", description: "Current OTP code is required to change the password or OTP auth." } } });
+    }
+    if (account.otpUrl && !checkOtp(code!)) {
+      return setResp({ notUpdated: { singleton: { type: "forbidden", description: "Current secret is incorrect." } } });
+    }
+    const secret = patch.secret as string | undefined;
+    if (secret !== undefined && secret !== MASKED) {
+      if (secret.length < 8) {
+        return setResp({ notUpdated: { singleton: { type: "invalidProperties", properties: ["secret"], description: "Password must be at least 8 characters long." } } });
+      }
+      account.password = secret;
+    }
+    if ("otpAuth/otpUrl" in patch) {
+      const url = patch["otpAuth/otpUrl"] as string | null;
+      if (url !== MASKED) account.otpUrl = url;
+    }
+    state.n++;
+    return setResp({ updated: { singleton: null } });
+  },
+  /*
+   * Push subscriptions. The JMAP half can be modeled; delivery cannot -- that
+   * runs through the browser vendor's real push service, so nothing local will
+   * ever make a notification appear.
+   *
+   * What is worth reproducing is the handshake, because it is the part that
+   * fails quietly: a subscription is created unverified and stays silent until
+   * the client echoes back a code the server pushed. A mock that marked one
+   * verified on creation would let a client ship without ever implementing
+   * that, and the symptom in production is "registered, and no notifications".
+   */
+  "PushSubscription/get": (a) => {
+    const ids = (a.ids as string[] | null) ?? pushSubscriptions.map((s) => s.id as string);
+    const list = pushSubscriptions.filter((s) => ids.includes(s.id as string));
+    // `keys` is write-only in JMAP: the server never hands it back.
+    return { accountId: ACCOUNT, state: String(state.n), list: list.map((s) => { const { keys: _drop, ...rest } = s; return rest; }), notFound: ids.filter((i) => !list.some((s) => s.id === i)) };
+  },
+  "PushSubscription/set": (a) => {
+    const created: Obj = {};
+    const notCreated: Obj = {};
+    const updated: Obj = {};
+    const notUpdated: Obj = {};
+    const destroyed: string[] = [];
+    for (const [cid, obj] of Object.entries((a.create as Obj) ?? {})) {
+      const o = obj as Obj;
+      const keys = (o.keys ?? {}) as Obj;
+      // Stalwart 0.16 was fixed to accept the unpadded base64url the W3C Push
+      // API produces; padding it would be the client inventing a shape.
+      for (const k of ["p256dh", "auth"]) {
+        const v = String(keys[k] ?? "");
+        if (!v) { notCreated[cid] = { type: "invalidProperties", properties: ["keys"], description: `Missing ${k}.` }; break; }
+        if (v.includes("=") || v.includes("+") || v.includes("/")) {
+          notCreated[cid] = { type: "invalidProperties", properties: ["keys"], description: `${k} must be unpadded base64url.` };
+          break;
+        }
+      }
+      if (notCreated[cid]) continue;
+      if (!String(o.url ?? "").startsWith("https://")) {
+        notCreated[cid] = { type: "invalidProperties", properties: ["url"], description: "Push endpoint must be https." };
+        continue;
+      }
+      // A filter condition with a null value is not a filter -- the real server
+      // answers "Invalid filter" and refuses the whole subscription. ihasmail
+      // shipped `inMailbox: null` meaning "the inbox", which meant nothing at
+      // all here, and the mock accepted it happily. It does not any more.
+      const badFilter = Object.entries((o.emailPush ?? {}) as Obj).find(([, cfg]) => {
+        const f = ((cfg as Obj)?.filter ?? {}) as Obj;
+        return Object.values(f).some((v) => v === null || v === undefined);
+      });
+      if (badFilter) {
+        notCreated[cid] = { type: "invalidArguments", properties: ["emailPush"], description: "Invalid filter." };
+        continue;
+      }
+      /*
+       * As Stalwart does (checked live on 0.16.22, 2026-09-16): a repeated
+       * deviceClientId is a second subscription, not a replacement -- this mock
+       * used to replace, which is how the client's pile-up never showed here
+       * (#375) -- and an account holds at most fifteen.
+       */
+      const deviceId = String(o.deviceClientId ?? "");
+      if (pushSubscriptions.length >= MAX_PUSH_SUBSCRIPTIONS) {
+        notCreated[cid] = { type: "overQuota", description: "There are too many subscriptions, please delete some before adding a new one." };
+        continue;
+      }
+      const id = `ps${randomUUID().slice(0, 6)}`;
+      /*
+       * A subscription expires, and this used to hand back `expires: null`.
+       * That is the one shape that makes the client's real problem invisible in
+       * development: JMAP puts a ceiling of seven days on a push subscription
+       * and expects the client to re-register before it lapses, so a client
+       * that never renews works perfectly against a mock that never expires
+       * anything and goes silent a week after being deployed. Seven days here,
+       * so "does this client renew?" is a question the mock can answer.
+       */
+      const expires = new Date(Date.now() + PUSH_TTL_MS).toISOString();
+      // An empty or missing list means every type, not none.
+      const types = Array.isArray(o.types) && o.types.length ? o.types : ALL_PUSH_TYPES;
+      pushSubscriptions.push({ id, deviceClientId: deviceId, url: o.url, types, emailPush: o.emailPush ?? null, expires, keys, verified: false, code: `v${randomUUID().slice(0, 8)}` });
+      created[cid] = { id, expires };
+      state.n++;
+    }
+    for (const [id, patch] of Object.entries((a.update as Obj) ?? {})) {
+      const s = pushSubscriptions.find((x) => x.id === id);
+      if (!s) { notUpdated[id] = { type: "notFound" }; continue; }
+      const code = (patch as Obj).verificationCode;
+      if (code !== undefined) {
+        if (code !== s.code) { notUpdated[id] = { type: "invalidProperties", properties: ["verificationCode"], description: "Verification code does not match." }; continue; }
+        s.verified = true;
+      }
+      // An expiry can be extended, up to the same seven days a new one gets.
+      const wanted = (patch as Obj).expires;
+      if (typeof wanted === "string") {
+        const at = Math.min(Date.parse(wanted), Date.now() + PUSH_TTL_MS);
+        if (Number.isNaN(at)) { notUpdated[id] = { type: "invalidProperties", properties: ["expires"] }; continue; }
+        s.expires = new Date(at).toISOString();
+      }
+      updated[id] = null;
+      state.n++;
+    }
+    for (const id of (a.destroy as string[]) ?? []) {
+      const i = pushSubscriptions.findIndex((x) => x.id === id);
+      if (i >= 0) { pushSubscriptions.splice(i, 1); destroyed.push(id); state.n++; }
+    }
+    return setResp({ created, notCreated, updated, notUpdated, destroyed });
+  },
+  "x:AppPassword/get": (a) => genericGet(account.appPasswords)(a),
+  "x:AppPassword/set": (a) => {
+    const created: Obj = {};
+    const destroyed: string[] = [];
+    for (const [cid, obj] of Object.entries((a.create as Obj) ?? {})) {
+      const id = `ap${randomUUID().slice(0, 6)}`;
+      // Real app passwords carry their credential id, so the server can spot
+      // one by its shape alone. Mirror that.
+      const secret = `$app$${id}$${randomUUID().replace(/-/g, "").slice(0, 20)}`;
+      const row: Obj = { id, description: (obj as Obj).description ?? "App password", createdAt: new Date().toISOString(), expiresAt: null, secret };
+      account.appPasswords.push(row);
+      created[cid] = { id, secret, createdAt: row.createdAt };
+    }
+    for (const id of (a.destroy as string[]) ?? []) {
+      const i = account.appPasswords.findIndex((x) => x.id === id);
+      if (i >= 0) { account.appPasswords.splice(i, 1); destroyed.push(id); }
+    }
+    state.n++;
+    return setResp({ created, destroyed });
+  },
+  "Identity/get": genericGet(identities),
+  "Identity/set": (a) => {
+    // Stalwart's cap is `value.len() < 2048` on a Rust string: 2047 bytes of
+    // UTF-8, not characters. Anything longer is refused by name.
+    for (const [where, entries] of [["notCreated", (a.create as Obj) ?? {}], ["notUpdated", (a.update as Obj) ?? {}]] as const) {
+      for (const [key, obj] of Object.entries(entries)) {
+        const over = ["htmlSignature", "textSignature"].find((prop) => {
+          const v = (obj as Obj)[prop];
+          return typeof v === "string" && Buffer.byteLength(v, "utf8") > 2047;
+        });
+        if (over) return setResp({ [where]: { [key]: { type: "invalidProperties", properties: [over], description: "Invalid property." } } });
+      }
+    }
+    return genericSet(identities, "i", (o) => Object.assign(o, { replyTo: null, bcc: null, textSignature: "", htmlSignature: "", mayDelete: true, ...o }))(a);
+  },
+  "EmailSubmission/get": (a) => {
+    const ids = a.ids as string[] | null | undefined;
+    const found = ids ? ids.map((id) => submissions.find((x) => x.id === id)).filter(Boolean) as Obj[] : submissions;
+    return { accountId: ACCOUNT, state: String(state.n), list: found.map((x) => pick(submissionView(x), a.properties as string[] | null)), notFound: ids ? ids.filter((id) => !submissions.some((x) => x.id === id)) : [] };
+  },
+  "EmailSubmission/query": (a) => {
+    const list = submissions.filter((s) => matchSubmissionFilter(s, a.filter as Obj | undefined));
+    list.sort((x, y) => String(x.sendAt).localeCompare(String(y.sendAt)));
+    const pos = Number(a.position ?? 0);
+    const limit = Number(a.limit ?? 50);
+    return { accountId: ACCOUNT, queryState: String(state.n), canCalculateChanges: false, position: pos, ids: list.slice(pos, pos + limit).map((s) => s.id), total: list.length, limit };
+  },
+  "EmailSubmission/set": (a) => {
+    const created: Obj = {};
+    const notCreated: Obj = {};
+    const updated: Obj = {};
+    const notUpdated: Obj = {};
+    for (const [cid, raw] of Object.entries((a.create as Obj) ?? {})) {
+      const sub = raw as Obj;
+      const emailId = sub.emailId as string;
+      const e = emails.find((x) => x.id === emailId);
+      if (!e) {
+        notCreated[cid] = { type: "invalidProperties", properties: ["emailId"], description: "Blob for email not found." };
+        continue;
+      }
+      const hold = holdUntilOf(sub.envelope as Obj | undefined, Date.now());
+      if (Number.isNaN(hold)) {
+        notCreated[cid] = { type: "invalidProperties", properties: ["envelope"], description: "Failed to parse mailFrom parameters." };
+        continue;
+      }
+      // Stalwart rejects MAIL FROM outright past its own limit.
+      if (hold !== null && hold > Date.now() + MAX_DELAYED_SEND * 1000) {
+        notCreated[cid] = { type: "forbiddenMailFrom", description: `Server rejected MAIL-FROM: 501 5.5.4 Requested release time exceeds maximum of ${new Date(Date.now() + MAX_DELAYED_SEND * 1000).toISOString()}.` };
+        continue;
+      }
+      // With the MTA extension off, the hold is dropped in silence.
+      const sendAt = hold !== null && !NO_FUTURE_RELEASE ? hold : Date.now();
+      const rec: Obj = {
+        id: `s${randomUUID().slice(0, 6)}`,
+        identityId: sub.identityId ?? null,
+        emailId,
+        threadId: e.threadId ?? null,
+        envelope: sub.envelope ?? null,
+        sendAt: new Date(sendAt).toISOString(),
+        undoStatus: null,
+        deliveryStatus: null,
+      };
+      submissions.push(rec);
+      created[cid] = { id: rec.id, sendAt: rec.sendAt, undoStatus: undoStatusOf(rec, Date.now()) };
+      const patch = ((a.onSuccessUpdateEmail as Obj) ?? {})[`#${cid}`] as Obj | undefined;
+      if (patch) applyPatch(e, patch);
+    }
+    for (const [id, raw] of Object.entries((a.update as Obj) ?? {})) {
+      const patch = raw as Obj;
+      const sub = submissions.find((x) => x.id === id);
+      if (!sub) { notUpdated[id] = { type: "notFound" }; continue; }
+      if (patch.undoStatus !== "canceled") {
+        notUpdated[id] = { type: "invalidProperties", properties: ["undoStatus"], description: "Only cancellation is supported." };
+        continue;
+      }
+      const status = undoStatusOf(sub, Date.now());
+      if (status !== "pending") {
+        notUpdated[id] = { type: "cannotUnsend", description: status === "canceled" ? "The message was already canceled." : "The message has already been sent." };
+        continue;
+      }
+      sub.undoStatus = "canceled";
+      updated[id] = null;
+    }
+    recount();
+    return setResp({
+      created,
+      updated,
+      ...(Object.keys(notCreated).length ? { notCreated } : {}),
+      ...(Object.keys(notUpdated).length ? { notUpdated } : {}),
+    });
+  },
+  "VacationResponse/get": () => ({ accountId: ACCOUNT, state: "1", list: [vacationBox.current], notFound: [] }),
+  "VacationResponse/set": (a) => { const p = ((a.update as Obj) ?? {}).singleton as Obj | undefined; if (p) vacationBox.current = { ...vacationBox.current, ...p }; return setResp({ updated: { singleton: null } }); },
+  "Quota/get": () => ({ accountId: ACCOUNT, state: "1", list: [{ id: "q1", resourceType: "octets", used: 734003200, hardLimit: 2147483648, scope: "account", name: "Storage", types: ["Email"] }], notFound: [] }),
+  "SieveScript/get": genericGet(sieveScripts),
+  "SieveScript/set": (a) => { const r = genericSet(sieveScripts, "sv", (o) => Object.assign(o, { isActive: false, ...o }))(a); const act = (a.onSuccessActivateScript as string | undefined); if (act) { const id = act.startsWith("#") ? ((r.created as Obj)[act.slice(1)] as Obj)?.id : act; for (const s of sieveScripts) s.isActive = s.id === id; } if (a.onSuccessDeactivateScript) for (const s of sieveScripts) s.isActive = false; return r; },
+  "SieveScript/validate": () => ({ accountId: ACCOUNT, error: null }),
+  "Calendar/get": (a) => genericGet(calendarsFor(a.accountId))(a),
+  "Calendar/set": (a) => genericSet(calendarsFor(a.accountId), "c", (o) => Object.assign(o, { color: "#0f766e", isSubscribed: true, isVisible: true, isDefault: false, includeInAvailability: "all", timeZone: null, shareWith: null, myRights: rightsCal(), description: null, sortOrder: 0, ...o }))(a),
+  /*
+   * With `expandRecurrences` every id that comes back is synthetic — a one-off
+   * included, which is what a live 0.16.19 does and what makes `baseEventId`
+   * useless as a test for a series. Without it (the `findByUid` path) the
+   * stored ids come back untouched, because callers hand those straight to a
+   * destroy and mean the whole event.
+   */
+  "CalendarEvent/query": (a) => {
+    const list = eventsFor(a.accountId);
+    const filter = (a.filter as Obj) ?? {};
+    const matching = list.filter((e) => !filter.uid || e.uid === filter.uid);
+    if (!a.expandRecurrences) {
+      return { accountId: a.accountId ?? ACCOUNT, queryState: "1", canCalculateChanges: false, position: 0, ids: matching.map((e) => e.id), total: matching.length };
+    }
+    const from = filter.after ? new Date(filter.after as string) : new Date(-8640000000000);
+    const to = filter.before ? new Date(filter.before as string) : new Date(8640000000000);
+    const ids: string[] = [];
+    for (const e of matching) for (const occ of expandOccurrences(e, from, to)) ids.push(syntheticId(e.id as string, occ.recurrenceId));
+    return { accountId: a.accountId ?? ACCOUNT, queryState: "1", canCalculateChanges: false, position: 0, ids, total: ids.length };
+  },
+  "CalendarEvent/get": (a) => {
+    const list = eventsFor(a.accountId);
+    const ids = a.ids as string[] | null | undefined;
+    const properties = a.properties as string[] | null | undefined;
+    // With no ids every event comes back under its stored id, none synthetic.
+    if (!ids) return { accountId: ACCOUNT, state: String(state.n), list: list.map((x) => eventGetView(x, false, properties)), notFound: [] };
+    const found: Obj[] = [];
+    const notFound: string[] = [];
+    for (const id of ids) {
+      const resolved = resolveEvent(list, id);
+      if (!resolved) { notFound.push(id); continue; }
+      found.push(resolved.occ ? eventGetView(occurrenceView(resolved.base, resolved.occ), true, properties) : eventGetView(resolved.base, false, properties));
+    }
+    return { accountId: ACCOUNT, state: String(state.n), list: found, notFound };
+  },
+  // Stalwart 0.16 rejects the RFC 8984 array outright and silently discards
+  // participants addressed the RFC 8984 way. The mock did neither, which is how
+  // #26 and #30 reached a live server unnoticed — so it now does both.
+  "CalendarEvent/set": (a) => calendarEventSet(a),
+  "CalendarEvent/parse": (a) => calendarEventParse(a),
+  "ParticipantIdentity/get": genericGet(participantIdentities),
+  "Principal/query": () => ({ accountId: ACCOUNT, queryState: "1", canCalculateChanges: false, position: 0, ids: principals.map((p) => p.id) }),
+  "Principal/get": genericGet(principals),
+  // One busy block a day across whatever range was asked for. It used to answer
+  // with a single block on the first day whatever the range, which was all an
+  // availability bar a day wide could show -- and left a bar covering several
+  // days looking as though everyone were free for all but the first of them.
+  "Principal/getAvailability": (a) => {
+    const from = new Date(String(a.utcStart));
+    const to = new Date(String(a.utcEnd));
+    const list: Obj[] = [];
+    for (let day = new Date(from); day < to && list.length < 31; day.setUTCDate(day.getUTCDate() + 1)) {
+      const date = day.toISOString().slice(0, 11);
+      list.push({ utcStart: `${date}13:00:00Z`, utcEnd: `${date}14:30:00Z`, busyStatus: "confirmed", event: null });
+    }
+    return { accountId: ACCOUNT, list };
+  },
+  "AddressBook/get": (a) => genericGet(booksFor(a.accountId))(a),
+  "AddressBook/set": (a) => {
+    /* Stalwart refuses any update to a book shared read-only, `isSubscribed`
+       included -- "You are not allowed to modify this address book", confirmed
+       live on 0.16.19 (2026-08-27) from the account holding the share. A mock
+       that accepted it would have agreed that subscribing works, which is
+       exactly the belief that shipped. Calendars accept the same write; the
+       difference is the server's, not ours. */
+    if (a.accountId === SHARED_ACCOUNT && a.update) {
+      const notUpdated: Obj = {};
+      for (const id of Object.keys(a.update as Obj)) notUpdated[id] = { type: "forbidden", description: "You are not allowed to modify this address book." };
+      return { accountId: a.accountId, oldState: String(state.n), newState: String(state.n), updated: null, notUpdated };
+    }
+    return genericSet(booksFor(a.accountId), "ab", (o) => Object.assign(o, { description: null, sortOrder: 0, isDefault: false, isSubscribed: true, shareWith: {}, myRights: abRights(), ...o }))(a);
+  },
+  "ContactCard/query": (a) => { const list = a.accountId === SHARED_ACCOUNT ? sharedCards : cards; return { accountId: a.accountId ?? ACCOUNT, queryState: "1", canCalculateChanges: false, position: 0, ids: list.map((c) => c.id), total: list.length }; },
+  // An empty `properties` list returns `id` alone, which `pick` already does.
+  // 0.16.22 made Stalwart agree; through 0.16.21 it returned every property.
+  "ContactCard/get": (a) => genericGet(a.accountId === SHARED_ACCOUNT ? sharedCards : cards)(a),
+  /*
+   * Recorded and announced like Email/set, so the client's incremental sync
+   * (`ContactCard/changes`, then fetching what it names) runs here too. A
+   * state older than the log's window cannot be answered, as on a real server.
+   */
+  "ContactCard/set": (a) => {
+    /*
+     * Stalwart refuses a `blobId` inside `media` (0.16.22, checked live on
+     * 2026-09-16), and takes the whole call down for it. The mock took
+     * anything, which is how ihasmail shipped a photo upload that never
+     * worked against the real server (#376).
+     */
+    const withBlobMedia = (o: unknown) => Object.values(((o as Obj)?.media as Record<string, Obj> | null) ?? {}).some((m) => m && "blobId" in m);
+    const refuse = { type: "invalidProperties", description: "blobIds in media is not supported.", properties: ["media"] };
+    const create = { ...((a.create as Obj) ?? {}) };
+    const update = { ...((a.update as Obj) ?? {}) };
+    const notCreated: Obj = {};
+    const notUpdated: Obj = {};
+    for (const [k, v] of Object.entries(create)) if (withBlobMedia(v)) { notCreated[k] = refuse; delete create[k]; }
+    for (const [k, v] of Object.entries(update)) if (withBlobMedia(v)) { notUpdated[k] = refuse; delete update[k]; }
+    const r = genericSet(cards, "cc")({ ...a, create, update });
+    if (Object.keys(notCreated).length) r.notCreated = { ...((r.notCreated as Obj) ?? {}), ...notCreated };
+    if (Object.keys(notUpdated).length) r.notUpdated = notUpdated;
+    nextState();
+    recordCardChange({
+      created: Object.values((r.created ?? {}) as Record<string, { id: string }>).map((x) => x.id),
+      updated: Object.keys((r.updated ?? {}) as Obj),
+      destroyed: (r.destroyed as string[] | undefined) ?? [],
+    });
+    broadcast(["ContactCard"]);
+    return r;
+  },
+  "ContactCard/changes": (a) => {
+    const since = Number(a.sinceState ?? 0);
+    if (since < cardLog.floor) throw new MethodError("cannotCalculateChanges", "That state is too old to answer from.");
+    const relevant = cardChanges.filter((c) => c.state > since);
+    const pick = (k: "created" | "updated" | "destroyed") => [...new Set(relevant.flatMap((c) => c[k]))];
+    return { accountId: a.accountId ?? ACCOUNT, oldState: String(a.sinceState ?? "1"), newState: String(state.n), hasMoreChanges: false, created: pick("created"), updated: pick("updated"), destroyed: pick("destroyed") };
+  },
+  "ContactCard/parse": (a) => { const parsed: Obj = {}; for (const b of a.blobIds as string[]) { const t = blobs.get(b)?.data.toString() ?? ""; const fn = /^FN:(.*)$/m.exec(t)?.[1]?.trim() ?? "Imported"; const em = /^EMAIL[^:]*:(.*)$/m.exec(t)?.[1]?.trim(); parsed[b] = [{ "@type": "Card", version: "1.0", uid: randomUUID(), kind: "individual", name: { full: fn }, emails: em ? { e1: { address: em } } : undefined }]; } return { accountId: ACCOUNT, parsed, notParsable: [] }; },
+  "FileNode/query": (a) => {
+    const f = (a.filter as Obj) ?? {};
+    const fileNodes = nodesFor(a.accountId);
+    // `nodeType` is a filter 0.16.19 really applies -- checked live on
+    // 2026-08-27, where it returned the two directories out of seven nodes. The
+    // mock ignoring it was worse than not having it: the sidebar tree asks for
+    // directories and was handed files, which it then drew as folders.
+    const list = fileNodes.filter((n) => {
+      if (f.isTopLevel ? n.parentId != null : f.parentId ? n.parentId !== f.parentId : false) return false;
+      if (f.nodeType && n.nodeType !== f.nodeType) return false;
+      return true;
+    });
+    return { accountId: ACCOUNT, queryState: "1", canCalculateChanges: false, position: 0, ids: list.map((n) => n.id), total: list.length };
+  },
+  "FileNode/get": (a) => genericGet(nodesFor(a.accountId))(a),
+  "FileNode/set": (a) => {
+    return genericSet(nodesFor(a.accountId), "f", (o) => {
+      Object.assign(o, { created: new Date().toISOString(), modified: new Date().toISOString(), myRights: fr(), shareWith: {}, size: o.blobId ? (blobs.get(o.blobId as string)?.data.length ?? 0) : null, type: o.type ?? null, blobId: o.blobId ?? null, ...o });
+      // Without nodeType, a node is a directory precisely when it carries no
+      // file properties. Keep it internally so query and get stay consistent.
+      if (!o.nodeType) o.nodeType = o.blobId || o.size != null || o.type ? "file" : "directory";
+    })(a);
+  },
+};
+
@@ -133,3 +133,55 @@ test("a tab on the relay is moved to fan-out when its account verifies, and its
    assert.match(out.written.at(-1) ?? "", /StateChange/, "the same browser stream now receives fan-out");
  } finally { restore(); }
 });
+
+test("a new subscription clears what this installation left behind, and only that", async () => {
+  // What a restart finds: its own subscription from the last process, another
+  // installation's on the same server, a browser's, and the old id format.
+  const calls: Array<[string, Record<string, unknown>]> = [];
+  let ownPrefix = "";
+  const real = globalThis.fetch;
+  globalThis.fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
+    const url = String(input);
+    if (url.endsWith("/.well-known/jmap") || url.includes("/jmap/session")) {
+      return new Response(JSON.stringify({ apiUrl: "http://127.0.0.1:1/jmap/", primaryAccounts: { "urn:ietf:params:jmap:mail": "a" },
+        accounts: { a: {} }, capabilities: {}, eventSourceUrl: "", downloadUrl: "", uploadUrl: "", state: "s" }), { status: 200, headers: { "content-type": "application/json" } });
+    }
+    const { methodCalls } = JSON.parse(String(init?.body)) as { methodCalls: [string, Record<string, unknown>, string][] };
+    const [name, args, id] = methodCalls[0]!;
+    calls.push([name, args]);
+    let result: Record<string, unknown> = {};
+    if (name === "PushSubscription/get") {
+      result = { list: [
+        { id: "mine-before", deviceClientId: `${ownPrefix}oldtoken` },
+        { id: "other-install", deviceClientId: "ihasmail-proxy-ZZZZZZZZZZ-12345678" },
+        { id: "a-browser", deviceClientId: "ihasmail-00000000-0000-4000-8000-000000000001" },
+        { id: "old-format", deviceClientId: "ihasmail-Ab3_x9Qz" },
+      ] };
+    } else if (name === "PushSubscription/set" && args.create) {
+      const body = (args.create as Record<string, { deviceClientId: string }>).s!;
+      result = { created: { s: { id: "fresh", expires: new Date(Date.now() + 7 * 86_400_000).toISOString() } } };
+      calls.at(-1)![1] = { ...args, deviceClientId: body.deviceClientId };
+    } else {
+      result = { destroyed: args.destroy };
+    }
+    return new Response(JSON.stringify({ methodResponses: [[name, result, id]] }), { status: 200, headers: { "content-type": "application/json" } });
+  }) as typeof fetch;
+  try {
+    // The installation's prefix, learned the way the server makes it: from its first create.
+    push.prepare("[email protected]", "a", "Basic p");
+    await new Promise((r) => setTimeout(r, 30));
+    const firstCreate = calls.find(([n, a]) => n === "PushSubscription/set" && a.create);
+    const deviceId = String(firstCreate?.[1].deviceClientId ?? "");
+    assert.match(deviceId, /^ihasmail-proxy-[A-Za-z0-9_-]{10}-[A-Za-z0-9_-]{8}$/, "the server's own prefix, naming the installation");
+    ownPrefix = deviceId.slice(0, deviceId.lastIndexOf("-") + 1);
+
+    calls.length = 0;
+    push.prepare("[email protected]", "a", "Basic r");
+    await new Promise((r) => setTimeout(r, 30));
+    const destroyed = calls.filter(([n, a]) => n === "PushSubscription/set" && a.destroy).flatMap(([, a]) => a.destroy as string[]);
+    assert.deepEqual(destroyed, ["mine-before"], "only this installation's leftover goes");
+    assert.ok(calls.some(([n, a]) => n === "PushSubscription/set" && a.create), "and a new one is made");
+  } finally {
+    globalThis.fetch = real;
+  }
+});
@@ -23,7 +23,7 @@
 * transition loses no events, because a tab opened before verification keeps
 * its own relay for its whole life.
 */
-import { randomBytes } from "node:crypto";
+import { createHash, randomBytes } from "node:crypto";
 import type { ServerResponse } from "node:http";
 import { config } from "./config.js";
 import { absoluteUpstream, getUpstreamSession, upstreamFor } from "./upstream.js";
@@ -71,10 +71,58 @@ async function jmap(entry: AccountPush, calls: unknown[]) {
  return (await res.json()) as { methodResponses: [string, Record<string, unknown>, string][] };
 }

+/*
+ * Whose subscriptions are whose.
+ *
+ * Each process used to register a subscription per account and forget it when
+ * it stopped -- state here is in memory, and an immutable deployment restarts
+ * on every deploy -- so each restart left one more behind, receiving 404s until
+ * it expired. Stalwart keeps them all and allows fifteen per account (checked
+ * live on 0.16.22, 2026-09-16), which the browser subscriptions count against
+ * too (#375).
+ *
+ * So the device id names the installation -- a hash of the address Stalwart
+ * posts to, stable across restarts and different for another installation on
+ * the same server -- and a new subscription first removes the ones this
+ * installation left before. The `ihasmail-proxy-` prefix keeps them apart from
+ * the browsers' own, which the web client may clear to make room.
+ */
+function installationId(): string {
+  return createHash("sha256").update(`${config.pushUrl}${config.basePath}`).digest("base64url").slice(0, 10);
+}
+
+function deviceIdFor(entry: AccountPush): string {
+  return `ihasmail-proxy-${installationId()}-${entry.token.slice(0, 8)}`;
+}
+
+async function removeLeftovers(entry: AccountPush) {
+  const mine = `ihasmail-proxy-${installationId()}-`;
+  const r = await jmap(entry, [["PushSubscription/get", { ids: null, properties: ["id", "deviceClientId"] }, "0"]]);
+  const list = (r.methodResponses[0]?.[1] as { list?: Array<{ id: string; deviceClientId?: string }> }).list ?? [];
+  const stale = list.filter((s) => s.id !== entry.subscriptionId && String(s.deviceClientId ?? "").startsWith(mine)).map((s) => s.id);
+  if (stale.length) await jmap(entry, [["PushSubscription/set", { destroy: stale }, "0"]]);
+}
+
+/** Give the live subscription another week, rather than registering a second one. */
+async function renew(entry: AccountPush) {
+  const expires = new Date(Date.now() + 7 * 86_400_000).toISOString().replace(/\.\d+Z$/, "Z");
+  const r = await jmap(entry, [["PushSubscription/set", { update: { [entry.subscriptionId!]: { expires } } }, "0"]]);
+  const res = r.methodResponses[0]?.[1] as { updated?: Record<string, unknown>; notUpdated?: Record<string, unknown> };
+  if (!res.updated || !(entry.subscriptionId! in res.updated)) throw new Error("subscription not extended");
+  const got = await jmap(entry, [["PushSubscription/get", { ids: [entry.subscriptionId], properties: ["expires"] }, "0"]]);
+  const after = (got.methodResponses[0]?.[1] as { list?: Array<{ expires?: string | null }> }).list?.[0]?.expires;
+  entry.expires = after ? Date.parse(after) : Date.parse(expires);
+}
+
 async function subscribe(entry: AccountPush) {
+  try {
+    await removeLeftovers(entry);
+  } catch (err) {
+    console.warn(`[ihasmail] push: could not clear old subscriptions for ${entry.username}: ${(err as Error).message}`);
+  }
  const url = `${config.pushUrl!.replace(/\/$/, "")}${config.basePath}/api/push/${entry.token}`;
  const r = await jmap(entry, [["PushSubscription/set", {
-    create: { s: { deviceClientId: `ihasmail-${entry.token.slice(0, 8)}`, url,
+    create: { s: { deviceClientId: deviceIdFor(entry), url,
                   types: ["Email", "Mailbox", "Thread", "Identity", "EmailSubmission", "VacationResponse"] } },
  }, "0"]]);
  const created = (r.methodResponses[0]?.[1] as { created?: Record<string, { id: string; expires?: string }> }).created?.s;
@@ -184,8 +232,13 @@ function startSweeper() {
        console.warn(`[ihasmail] push: no verification for ${entry.username} within ${VERIFY_TIMEOUT_MS / 1000}s; relay in use`);
      }
      if (entry.state === "verified" && entry.expires - now < RENEW_BEFORE_MS) {
-        entry.state = "pending"; entry.since = now;
-        subscribe(entry).catch(() => { entry.state = "failed"; });
+        // Extended in place, which keeps it verified. Only if the server will
+        // not is a new one registered, and that one has to verify again.
+        entry.expires = now + RENEW_BEFORE_MS;
+        renew(entry).catch(() => {
+          entry.state = "pending"; entry.since = Date.now();
+          subscribe(entry).catch(() => { entry.state = "failed"; });
+        });
      }
      if (entry.tabs.size === 0 && (entry.state === "failed" || now - entry.since > 10 * 60_000)) {
        void unsubscribe(entry);
@@ -0,0 +1,115 @@
+import { test, before, after } from "node:test";
+import assert from "node:assert/strict";
+
+/**
+ * How much a request may make the proxy hold in memory.
+ *
+ * Routes that read JSON take a small body and no more, whether or not anyone
+ * is signed in. The JMAP route streams straight through for a session that may
+ * administer; for one that may not, it reads the body to check it, and that
+ * read is capped in size, in how many one session runs at once, and in bytes
+ * across everyone.
+ */
+
+const PORT = 18813;
+process.env.MOCK_PORT = String(PORT);
+process.env.MOCK_USER = "[email protected]";
+process.env.MOCK_PASS = "demo-password";
+process.env.STALWART_URL = `http://127.0.0.1:${PORT}`;
+process.env.APP_SECRET = "test-secret-for-request-limits";
+
+const mock = await import("./mock/index.js");
+const { createApp } = await import("./app.js");
+const { rateLimitKey } = await import("./clientip.js");
+
+const app = createApp();
+const HEADERS = { "content-type": "application/json", "x-requested-with": "ihasmail" };
+let cookie = "";
+
+/** A body that arrives in chunks with no content-length, as a chunked upload does. */
+function chunked(size: number, chunk = 256 * 1024): ReadableStream<Uint8Array> {
+  let sent = 0;
+  return new ReadableStream({
+    pull(controller) {
+      if (sent >= size) return controller.close();
+      const n = Math.min(chunk, size - sent);
+      controller.enqueue(new Uint8Array(n).fill(0x20));
+      sent += n;
+    },
+  });
+}
+
+const jmap = (body: BodyInit) =>
+  app.request("/api/jmap", { method: "POST", headers: { ...HEADERS, cookie }, body, duplex: "half" } as RequestInit);
+
+before(async () => {
+  // Not remembered: a device that is not the person's own, so JMAP is checked.
+  const res = await app.request("/api/auth/login", { method: "POST", headers: HEADERS, body: JSON.stringify({ username: "[email protected]", password: "demo-password" }) });
+  assert.equal(res.status, 200, "login should succeed against the mock");
+  cookie = res.headers.get("set-cookie")!.split(";")[0]!;
+});
+
+after(() => {
+  (mock as { server?: { close(): void } }).server?.close();
+});
+
+test("sign-in refuses a large body by its length, before reading it", async () => {
+  const res = await app.request("/api/auth/login", {
+    method: "POST",
+    headers: { ...HEADERS, "content-length": String(200 * 1024 * 1024) },
+    body: "{}",
+  });
+  assert.equal(res.status, 413);
+});
+
+test("sign-in refuses a large chunked body without holding all of it", async () => {
+  const res = await app.request("/api/auth/login", { method: "POST", headers: HEADERS, body: chunked(2 * 1024 * 1024), duplex: "half" } as RequestInit);
+  assert.equal(res.status, 413);
+});
+
+test("other JSON routes are limited too", async () => {
+  const res = await app.request("/api/account/password", { method: "POST", headers: { ...HEADERS, cookie }, body: chunked(1024 * 1024), duplex: "half" } as RequestInit);
+  assert.equal(res.status, 413);
+});
+
+test("an ordinary checked JMAP request still goes through", async () => {
+  const res = await jmap(JSON.stringify({ using: ["urn:ietf:params:jmap:core", "urn:ietf:params:jmap:mail"], methodCalls: [["Mailbox/get", { accountId: "a1", ids: [] }, "0"]] }));
+  assert.equal(res.status, 200);
+});
+
+test("a JMAP request larger than the check allows is refused", async () => {
+  assert.equal((await jmap(chunked(5 * 1024 * 1024))).status, 413);
+});
+
+test("a JMAP request larger than a sign-in body is not caught by the small-body limit", async () => {
+  // 200 KB of whitespace around a real request: valid JSON, well past 64 KB.
+  const body = `${" ".repeat(200 * 1024)}{"using":["urn:ietf:params:jmap:core"],"methodCalls":[["Core/echo",{},"0"]]}`;
+  assert.equal((await jmap(body)).status, 200);
+});
+
+test("one session cannot hold more than a few checked reads at once", async () => {
+  // Bodies that never finish: each holds its slot until its stream fails.
+  const controllers: ReadableStreamDefaultController<Uint8Array>[] = [];
+  const pending: Promise<Response>[] = [];
+  for (let i = 0; i < 4; i++) {
+    const s = new ReadableStream<Uint8Array>({ start(c) { controllers.push(c); c.enqueue(new TextEncoder().encode("{")); } });
+    pending.push(jmap(s));
+  }
+  await new Promise((r) => setTimeout(r, 50));
+  const fifth = await jmap("{}");
+  assert.equal(fifth.status, 429);
+  assert.ok(fifth.headers.get("retry-after"));
+  for (const c of controllers) c.error(new Error("client went away"));
+  await Promise.allSettled(pending);
+  // The slots are given back once those requests end.
+  const again = await jmap(JSON.stringify({ using: ["urn:ietf:params:jmap:core"], methodCalls: [["Core/echo", {}, "0"]] }));
+  assert.equal(again.status, 200);
+});
+
+test("IPv6 addresses share a rate-limit key across their /64", () => {
+  assert.equal(rateLimitKey("2001:db8:1:2:aaaa::1"), rateLimitKey("2001:db8:1:2:ffff:ffff:ffff:ffff"));
+  assert.notEqual(rateLimitKey("2001:db8:1:2::1"), rateLimitKey("2001:db8:1:3::1"));
+  assert.equal(rateLimitKey("2001:db8:1:2::1"), "2001:db8:1:2::/64");
+  assert.equal(rateLimitKey("198.51.100.7"), "198.51.100.7");
+  assert.equal(rateLimitKey("unknown"), "unknown");
+});
@@ -1,6 +1,6 @@
 import { test } from "node:test";
 import assert from "node:assert/strict";
-import { SessionStore } from "./sessions.js";
+import { SessionStore, accountKey } from "./sessions.js";
 import { normalizeLocale } from "./upstream.js";
 import { deriveKey, open, seal, sha256 } from "./crypto.js";
 import { RateLimiter } from "./ratelimit.js";
@@ -30,6 +30,20 @@ test("session store creates, resolves, and refuses tampered cookies", () => {
  assert.equal(store.resolve(cookie), null);
 });

+test("sessions group by the account, however its name was typed", () => {
+  const store = new SessionStore("");
+  const key = accountKey("https://mail.example.com", "[email protected]");
+  const a = store.create({ username: "alice", account: key, password: "pw", remember: false, userAgent: "", ip: "" });
+  const b = store.create({ username: "[email protected]", account: accountKey("https://mail.example.com", "[email protected]"), password: "pw", remember: false, userAgent: "", ip: "" });
+  // The same name on another configured server is another account.
+  store.create({ username: "[email protected]", account: accountKey("https://other.example.net", "[email protected]"), password: "pw", remember: false, userAgent: "", ip: "" });
+  assert.equal(a.session.account, b.session.account);
+  assert.equal(store.listForUser(a.session.account).length, 2);
+  assert.equal(store.destroyAllForUser(a.session.account, a.session.id), 1);
+  assert.equal(store.resolve(b.cookie), null, "the other spelling was signed out");
+  assert.ok(store.resolve(a.cookie), "this session was kept");
+});
+
 test("persisted session data does not contain the password", () => {
  const store = new SessionStore("");
  store.create({ username: "u", password: "super-secret-pw", remember: true, userAgent: "", ip: "" });
@@ -13,6 +13,8 @@ export interface StoredSession {
  /** sealed JSON {username, password} */
  sealedCredentials: string;
  username: string;
+  /** Which account this is; see `accountKey`. Absent on sessions saved before it existed. */
+  account?: string;
  createdAt: number;
  lastSeenAt: number;
  expiresAt: number;
@@ -24,6 +26,8 @@ export interface StoredSession {
 export interface LiveSession {
  id: string;
  username: string;
+  /** See `accountKey`. */
+  account: string;
  /** Basic Authorization header value for upstream calls. */
  authorization: string;
  remember: boolean;
@@ -46,8 +50,27 @@ export interface SessionSummary {
  ip: string;
 }

+/**
+ * The key sessions are grouped by for "sign out everywhere else".
+ *
+ * Not the username as typed: Stalwart takes `[email protected]` and a bare
+ * `alice` as the same account, and a session opened either way was missing
+ * from the list and survived the sign-out. The server's own name for the
+ * account, lower-cased, and the server it lives on -- the same name on two
+ * configured servers is two accounts.
+ */
+export function accountKey(upstream: string, canonicalUsername: string): string {
+  return `${upstream}|${canonicalUsername.trim().toLowerCase()}`;
+}
+
+function accountOf(s: StoredSession): string {
+  return s.account ?? s.username.trim().toLowerCase();
+}
+
 export interface CreateSessionParams {
  username: string;
+  /** From `accountKey`; defaults to the lower-cased username. */
+  account?: string;
  password: string;
  remember: boolean;
  userAgent: string;
@@ -85,8 +108,9 @@ export interface SessionBackend {
  resolve(cookie: string | undefined): LiveSession | null;
  reseal(cookie: string | undefined, password: string): boolean;
  destroy(id: string): void;
-  destroyAllForUser(username: string, exceptId?: string): number;
-  listForUser(username: string): SessionSummary[];
+  /** `account` is an `accountKey`, as carried on `LiveSession.account`. */
+  destroyAllForUser(account: string, exceptId?: string): number;
+  listForUser(account: string): SessionSummary[];
 }

 const COOKIE_SEP = ".";
@@ -172,6 +196,7 @@ export class SessionStore implements SessionBackend {
      salt: salt.toString("base64"),
      sealedCredentials: seal(JSON.stringify({ u: params.username, p: params.password }), key),
      username: params.username,
+      account: params.account ?? params.username.trim().toLowerCase(),
      createdAt: now,
      lastSeenAt: now,
      expiresAt: now + ttl,
@@ -248,10 +273,10 @@ export class SessionStore implements SessionBackend {
    if (this.sessions.delete(id)) this.scheduleSave();
  }

-  destroyAllForUser(username: string, exceptId?: string): number {
+  destroyAllForUser(account: string, exceptId?: string): number {
    let n = 0;
    for (const [id, s] of this.sessions) {
-      if (s.username === username && id !== exceptId) {
+      if (accountOf(s) === account && id !== exceptId) {
        this.sessions.delete(id);
        n++;
      }
@@ -260,11 +285,11 @@ export class SessionStore implements SessionBackend {
    return n;
  }

-  listForUser(username: string): SessionSummary[] {
+  listForUser(account: string): SessionSummary[] {
    const out = [];
    for (const s of this.sessions.values()) {
-      if (s.username !== username) continue;
-      const { secretHash: _h, salt: _s, sealedCredentials: _c, ...rest } = s;
+      if (accountOf(s) !== account) continue;
+      const { secretHash: _h, salt: _s, sealedCredentials: _c, account: _a, ...rest } = s;
      out.push(rest);
    }
    return out;
@@ -274,6 +299,7 @@ export class SessionStore implements SessionBackend {
    return {
      id: s.id,
      username,
+      account: accountOf(s),
      authorization: `Basic ${Buffer.from(`${username}:${password}`, "utf8").toString("base64")}`,
      remember: s.remember,
      createdAt: s.createdAt,
@@ -0,0 +1,79 @@
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, writeFileSync, mkdirSync, utimesSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { brotliCompressSync, brotliDecompressSync, gunzipSync, gzipSync } from "node:zlib";
+
+/*
+ * The bundle goes out compressed once, at build time, and anything revalidated
+ * can be answered with a 304.
+ *
+ * Before this the server gzipped the bundle again for every request that asked,
+ * never offered Brotli, and sent no validator for the shell -- so each reload's
+ * revalidation of index.html and sw.js downloaded them in full.
+ */
+const root = mkdtempSync(join(tmpdir(), "ihasmail-precompressed-"));
+mkdirSync(join(root, "assets"));
+const js = `console.log(${JSON.stringify("x".repeat(4000))});\n`;
+writeFileSync(join(root, "assets", "app-a1b2c3.js"), js);
+writeFileSync(join(root, "assets", "app-a1b2c3.js.br"), brotliCompressSync(js));
+writeFileSync(join(root, "assets", "app-a1b2c3.js.gz"), gzipSync(js));
+writeFileSync(join(root, "assets", "plain-d4e5f6.js"), js);
+// A copy left over from an older build of the same name must not be served.
+writeFileSync(join(root, "assets", "stale-000000.js"), js);
+writeFileSync(join(root, "assets", "stale-000000.js.br"), brotliCompressSync("old"));
+const old = new Date(Date.now() - 60_000);
+utimesSync(join(root, "assets", "stale-000000.js.br"), old, old);
+writeFileSync(join(root, "sw.js"), "/* worker */\n");
+writeFileSync(join(root, "index.html"), "<!doctype html><title>t</title>");
+
+process.env.STATIC_DIR = root;
+process.env.STALWART_URL = "http://127.0.0.1:1";
+const { createApp } = await import("./app.js");
+const app = createApp();
+
+const get = (path: string, headers: Record<string, string> = {}) => app.request(path, { headers });
+
+test("Brotli is served where the browser takes it", async () => {
+  const res = await get("/assets/app-a1b2c3.js", { "accept-encoding": "gzip, deflate, br" });
+  assert.equal(res.status, 200);
+  assert.equal(res.headers.get("content-encoding"), "br");
+  assert.equal(res.headers.get("vary"), "Accept-Encoding");
+  assert.equal(res.headers.get("content-type"), "text/javascript; charset=utf-8");
+  assert.equal(brotliDecompressSync(Buffer.from(await res.arrayBuffer())).toString(), js);
+});
+
+test("gzip where Brotli is not accepted, and nothing where neither is", async () => {
+  const gz = await get("/assets/app-a1b2c3.js", { "accept-encoding": "gzip, br;q=0" });
+  assert.equal(gz.headers.get("content-encoding"), "gzip");
+  assert.equal(gunzipSync(Buffer.from(await gz.arrayBuffer())).toString(), js);
+  const plain = await get("/assets/app-a1b2c3.js");
+  assert.equal(plain.headers.get("content-encoding"), null);
+  assert.equal(await plain.text(), js);
+});
+
+test("a file without a copy is compressed as before", async () => {
+  const res = await get("/assets/plain-d4e5f6.js", { "accept-encoding": "gzip" });
+  assert.equal(res.headers.get("content-encoding"), "gzip");
+  assert.equal(gunzipSync(Buffer.from(await res.arrayBuffer())).toString(), js);
+});
+
+test("a copy older than its file is ignored", async () => {
+  const res = await get("/assets/stale-000000.js", { "accept-encoding": "br" });
+  assert.notEqual(res.headers.get("content-encoding"), "br");
+});
+
+test("the shell and the worker answer a revalidation with 304", async () => {
+  for (const path of ["/", "/sw.js"]) {
+    const first = await get(path);
+    const etag = first.headers.get("etag");
+    assert.ok(etag, `${path} carries a validator`);
+    await first.arrayBuffer();
+    const again = await get(path, { "if-none-match": etag! });
+    assert.equal(again.status, 304, `${path} is not sent again`);
+    assert.equal(await again.text(), "");
+    const changed = await get(path, { "if-none-match": `"something-else"` });
+    assert.equal(changed.status, 200);
+  }
+});
@@ -1,3 +1,4 @@
+import { createHash } from "node:crypto";
 import { createReadStream } from "node:fs";
 import { stat, readFile } from "node:fs/promises";
 import { extname, join, normalize, resolve, sep } from "node:path";
@@ -77,9 +78,61 @@ export const APP_CSP = [
  "manifest-src 'self'",
 ].join("; ");

+/*
+ * What a file is, for the purpose of "has it changed". The shell and the
+ * never-stale files are revalidated on every load; with no validator to send
+ * back, every revalidation downloaded the whole file again.
+ */
+function etagOf(size: number, mtimeMs: number): string {
+  return `W/"${size.toString(36)}-${Math.floor(mtimeMs).toString(36)}"`;
+}
+
+function notModified(c: Context, etag: string): boolean {
+  const sent = c.req.header("if-none-match");
+  return Boolean(sent && sent.split(",").some((t) => t.trim() === etag || t.trim() === "*"));
+}
+
+/*
+ * The encodings a build can carry beside a file, best first. See
+ * scripts/precompress.mjs, which writes them.
+ */
+const PRECOMPRESSED: Array<{ token: string; suffix: string; encoding: string }> = [
+  { token: "br", suffix: ".br", encoding: "br" },
+  { token: "gzip", suffix: ".gz", encoding: "gzip" },
+];
+
+function accepts(c: Context, token: string): boolean {
+  const header = c.req.header("accept-encoding") ?? "";
+  return header.split(",").some((part) => {
+    const [name, ...params] = part.trim().split(";");
+    if (name?.trim().toLowerCase() !== token) return false;
+    const q = params.map((p) => p.trim()).find((p) => p.startsWith("q="));
+    return !q || Number(q.slice(2)) > 0;
+  });
+}
+
 export function staticHandler(root: string, basePath = ""): Handler {
  const absRoot = resolve(root);
-  let indexCache: { body: string; mtime: number } | null = null;
+  let indexCache: { body: string; mtime: number; etag: string } | null = null;
+  /** Which precompressed copies exist, per file and modification time. */
+  const variants = new Map<string, { mtime: number; found: Map<string, number> }>();
+
+  async function variantsOf(filePath: string, mtime: number): Promise<Map<string, number>> {
+    const known = variants.get(filePath);
+    if (known && known.mtime === mtime) return known.found;
+    const found = new Map<string, number>();
+    for (const v of PRECOMPRESSED) {
+      try {
+        const st = await stat(filePath + v.suffix);
+        // A copy older than the file it came from describes something else.
+        if (st.isFile() && st.mtimeMs >= mtime) found.set(v.suffix, st.size);
+      } catch {
+        /* none */
+      }
+    }
+    variants.set(filePath, { mtime, found });
+    return found;
+  }
  let mismatchWarned = false;

  /**
@@ -107,13 +160,16 @@ export function staticHandler(root: string, basePath = ""): Handler {
      const p = join(absRoot, "index.html");
      const st = await stat(p);
      if (!indexCache || indexCache.mtime !== st.mtimeMs) {
-        indexCache = { body: await readFile(p, "utf8"), mtime: st.mtimeMs };
+        const body = await readFile(p, "utf8");
+        indexCache = { body, mtime: st.mtimeMs, etag: `"${createHash("sha256").update(body).digest("base64url").slice(0, 22)}"` };
        mismatchWarned = false;
      }
      warnOnBaseMismatch(indexCache.body);
      c.header("Content-Type", "text/html; charset=utf-8");
      c.header("Cache-Control", "no-cache");
      c.header("Content-Security-Policy", APP_CSP);
+      c.header("ETag", indexCache.etag);
+      if (notModified(c, indexCache.etag)) return c.body(null, 304);
      return c.body(indexCache.body);
    } catch {
      c.header("Content-Type", "text/plain; charset=utf-8");
@@ -142,7 +198,8 @@ export function staticHandler(root: string, basePath = ""): Handler {
      if (!st.isFile()) return serveIndex(c);
      const ext = extname(filePath).toLowerCase();
      c.header("Content-Type", MIME[ext] ?? "application/octet-stream");
-      c.header("Content-Length", String(st.size));
+      const etag = etagOf(st.size, st.mtimeMs);
+      c.header("ETag", etag);
      if (rel.startsWith("/assets/") || rel.startsWith("assets/")) {
        c.header("Cache-Control", "public, max-age=31536000, immutable");
      } else if (ext === ".html" || isNeverStale(rel, ext)) {
@@ -151,8 +208,23 @@ export function staticHandler(root: string, basePath = ""): Handler {
      } else {
        c.header("Cache-Control", "public, max-age=3600");
      }
+      if (notModified(c, etag)) return c.body(null, 304);
+      // Serve a copy made at build time where the browser takes one.
+      let servePath = filePath;
+      let size = st.size;
+      const found = await variantsOf(filePath, st.mtimeMs);
+      if (found.size) {
+        c.header("Vary", "Accept-Encoding");
+        const pick = PRECOMPRESSED.find((v) => found.has(v.suffix) && accepts(c, v.token));
+        if (pick) {
+          servePath = filePath + pick.suffix;
+          size = found.get(pick.suffix)!;
+          c.header("Content-Encoding", pick.encoding);
+        }
+      }
+      c.header("Content-Length", String(size));
      if (c.req.method === "HEAD") return c.body(null);
-      const stream = Readable.toWeb(createReadStream(filePath)) as ReadableStream;
+      const stream = Readable.toWeb(createReadStream(servePath)) as ReadableStream;
      return c.body(stream);
    } catch {
      // SPA fallback for client-side routes (no file extension) only.
@@ -233,6 +233,23 @@ export interface AccountInfo {

 const infoCache = new Map<string, { info: AccountInfo; fetchedAt: number }>();
 const INFO_CACHE_MS = 30 * 60_000;
+
+/*
+ * Both caches are keyed by session, and used to lose an entry only when that
+ * session signed out or was refused -- not when it simply expired, which is how
+ * most sessions end. An entry past its age is never used again, so dropping
+ * those on a timer is all it takes to stop them accumulating.
+ */
+export function sweepUpstreamCaches(now = Date.now()): void {
+  for (const [id, v] of sessionCache) if (now - v.fetchedAt >= SESSION_CACHE_MS) sessionCache.delete(id);
+  for (const [id, v] of infoCache) if (now - v.fetchedAt >= INFO_CACHE_MS) infoCache.delete(id);
+}
+setInterval(() => sweepUpstreamCaches(), SESSION_CACHE_MS).unref();
+
+/** How many sessions the caches hold; for tests. */
+export function upstreamCacheSizes(): { sessions: number; info: number } {
+  return { sessions: sessionCache.size, info: infoCache.size };
+}
 const EMPTY_INFO: AccountInfo = { locale: null, edition: null, permissions: [] };

 /**
@@ -6,7 +6,7 @@
  "type": "module",
  "scripts": {
    "dev": "vite",
-    "build": "tsc -p tsconfig.json --noEmit && vite build",
+    "build": "tsc -p tsconfig.json --noEmit && vite build && node ../scripts/precompress.mjs dist",
    "preview": "vite preview",
    "typecheck": "tsc -p tsconfig.json --noEmit",
    "test": "vitest run"
@@ -26,10 +26,76 @@ self.addEventListener("install", (event) => {

 self.addEventListener("activate", (event) => {
  event.waitUntil(
-    caches.keys().then((keys) => Promise.all(keys.filter((k) => k !== VERSION).map((k) => caches.delete(k)))).then(() => self.clients.claim())
+    caches.keys()
+      .then((keys) => Promise.all(keys.filter((k) => k !== VERSION).map((k) => caches.delete(k))))
+      .then(() => tidy())
+      .catch(() => {})
+      .then(() => self.clients.claim())
  );
 });

+/*
+ * Keeping the cache to what the current build uses.
+ *
+ * Build assets are cached on first use and their names change with every
+ * build, and nothing used to take them out again: every deploy's chunks stayed
+ * in the browser for good. Worse, whatever the server answered was kept -- a
+ * 404 for a chunk asked for while a deploy was changing over became that
+ * chunk, from then on, in that browser.
+ *
+ * The rule now: only a successful response is cached, and whenever the app
+ * page changes, the assets it no longer names are dropped. A lazily loaded
+ * chunk the page does not name is dropped too, and fetched again the next time
+ * it is wanted -- a hash that did not change is still on the server.
+ *
+ * The cache name stays as it is. The same cache carries what the worker leaves
+ * for a tab to collect -- a push verification, a share, the facts it notifies
+ * from -- and a new name would throw those away along with the rubbish.
+ */
+const ASSETS = `${BASE}/assets/`;
+const SHELL_KEY = `${BASE}/`;
+
+function assetsNamedIn(html) {
+  const out = new Set();
+  for (const m of html.matchAll(/["']([^"']*\/assets\/[^"']+)["']/g)) {
+    try {
+      out.add(new URL(m[1], self.location).pathname);
+    } catch {
+      /* not a URL */
+    }
+  }
+  return out;
+}
+
+/** Drop failed responses, and assets the cached app page does not name. */
+async function tidy() {
+  const cache = await caches.open(VERSION);
+  const shell = await cache.match(SHELL_KEY);
+  // Without a page to go by, which assets are current is unknown; keep them.
+  const keep = shell ? assetsNamedIn(await shell.text()) : null;
+  for (const req of await cache.keys()) {
+    const path = new URL(req.url).pathname;
+    if (path.startsWith(ASSETS)) {
+      if (keep && !keep.has(path)) {
+        await cache.delete(req);
+        continue;
+      }
+    }
+    const res = await cache.match(req);
+    if (res && !res.ok) await cache.delete(req);
+  }
+}
+
+/** Keep the offline copy of the app page current, and tidy when it changes. */
+async function refreshShell(res) {
+  const html = await res.text();
+  const cache = await caches.open(VERSION);
+  const prev = await cache.match(SHELL_KEY);
+  if (prev && (await prev.text()) === html) return;
+  await cache.put(SHELL_KEY, new Response(html, { headers: { "content-type": "text/html; charset=utf-8" } }));
+  await tidy();
+}
+
 /*
 * Where a share from the operating system is left for a tab to collect.
 *
@@ -103,12 +169,14 @@ self.addEventListener("fetch", (event) => {
  if (url.origin !== self.location.origin) return;
  if (url.pathname.startsWith(`${BASE}/api/`)) return;

-  // Hashed build assets: cache-first.
-  if (url.pathname.startsWith(`${BASE}/assets/`)) {
+  // Hashed build assets: cache-first, and only what actually arrived.
+  if (url.pathname.startsWith(ASSETS)) {
    event.respondWith(
      caches.match(req).then((hit) => hit || fetch(req).then((res) => {
-        const copy = res.clone();
-        caches.open(VERSION).then((c) => c.put(req, copy));
+        if (res.ok && res.type === "basic") {
+          const copy = res.clone();
+          event.waitUntil(caches.open(VERSION).then((c) => c.put(req, copy)).catch(() => {}));
+        }
        return res;
      }))
    );
@@ -117,7 +185,13 @@ self.addEventListener("fetch", (event) => {

  // Navigations & everything else: network-first, fall back to cached shell.
  if (req.mode === "navigate") {
-    event.respondWith(fetch(req).catch(() => caches.match(`${BASE}/`)));
+    event.respondWith(fetch(req).then((res) => {
+      // Every route is the same app page; a fresh one replaces the offline copy.
+      if (res.ok && (res.headers.get("content-type") || "").startsWith("text/html")) {
+        event.waitUntil(refreshShell(res.clone()).catch(() => {}));
+      }
+      return res;
+    }).catch(() => caches.match(SHELL_KEY)));
    return;
  }
  event.respondWith(fetch(req).catch(() => caches.match(req)));
@@ -272,6 +346,14 @@ self.addEventListener("push", (event) => {

  const emails = (data && data["@type"] === "EmailPush" && Array.isArray(data.emails)) ? data.emails : [];
  event.waitUntil((async () => {
+    /*
+     * Someone reading the app already knows. A focused, visible window of this
+     * app gets its new mail from its own event stream, so a notification on
+     * top of it is a second telling of the same thing (#375). Chrome does not
+     * require one while the site is in the foreground.
+     */
+    const windows = await self.clients.matchAll({ type: "window" });
+    if (windows.some((w) => w.focused && w.visibilityState === "visible")) return;
    const facts = await readFacts();
    const strings = facts?.strings ?? { newMail: "New mail", newMessage: "New message", noSubject: "(no subject)" };
    /*
@@ -287,8 +369,10 @@ self.addEventListener("push", (event) => {
    if ("setAppBadge" in self.navigator) await self.navigator.setAppBadge().catch(() => {});

    if (!emails.length) {
-      // A StateChange, or a payload too large to carry the message. Say
-      // something true rather than inventing a sender.
+      // A delivery from a server that sends StateChange rather than EmailPush
+      // -- the subscription asks for `EmailDelivery` only, so it is new mail --
+      // or a payload too large to carry the message. Say something true
+      // rather than inventing a sender.
      await self.registration.showNotification(strings.newMail, {
        icon: `${BASE}/img/icon-192.png`, badge: `${BASE}/img/favicon-64.png`, tag: "ihasmail-mail", data: { url: `${BASE}/mail` },
      });
@@ -308,7 +392,8 @@ self.addEventListener("push", (event) => {
        // be drawn.
        actions: email.id ? actionsFor(facts) : [],
        data: {
-          url: email.id ? `${BASE}/mail/inbox/${email.id}` : `${BASE}/mail`,
+          // The route names a conversation, and `m` the message in it.
+          url: email.id && email.threadId ? `${BASE}/mail/inbox/${email.threadId}?m=${encodeURIComponent(email.id)}` : `${BASE}/mail`,
          id: email.id || null,
          title,
          accountId: facts?.accountId ?? null,
@@ -16,12 +16,12 @@ import { LoginPage } from "@/views/Login";
 import { AppShell } from "@/views/AppShell";
 import { MailView } from "@/views/mail/MailView";
 import { ComposerDock } from "@/views/compose/ComposerDock";
-import { setUnreadBadge } from "@/lib/notify";
-import { publishWorkerFacts } from "@/lib/swFacts";
+import { requestNotificationPermission, setBaseTitle, setUnreadBadge } from "@/lib/notify/notify";
+import { publishWorkerFacts } from "@/lib/sw/swFacts";
 import { PAINTED_FROM_CACHE, useSettings, syncedPart } from "@/store/settings";
 import { armSettingsSync, loadRemoteSettings, queueSettingsPush, settingsAlreadyLoadedFor, settingsSyncAvailable } from "@/lib/settingsSync";
 import { loadSettingsPolicy } from "@/lib/settingsPolicy";
-import { listenForVerification, renewWebPush } from "@/lib/webpushEnable";
+import { listenForVerification, renewWebPush } from "@/lib/notify/webpushEnable";
 import { plural, t, useLanguageVersion, whenLanguageReady } from "@/lib/i18n";
 import { confirmLeaveUnsaved, hasUnsavedChanges } from "@/lib/unsavedChanges";
 import { BASE_PATH, withBase } from "@/lib/basePath";
@@ -260,10 +260,8 @@ function AuthedApp() {
  });
  const appName = useSession((s) => s.session?.ihasmail?.appName) || DEFAULT_APP_NAME;
  useEffect(() => {
-    void import("@/lib/notify").then((m) => {
-      m.setBaseTitle(appName);
-      setUnreadBadge(inboxUnread);
-    });
+    setBaseTitle(appName);
+    setUnreadBadge(inboxUnread);
  }, [inboxUnread, appName]);

  /*
@@ -284,7 +282,7 @@ function AuthedApp() {
  // Request notification permission lazily when enabled
  const notif = useSettings((s) => s.settings.desktopNotifications);
  useEffect(() => {
-    if (notif) void import("@/lib/notify").then((m) => m.requestNotificationPermission());
+    if (notif) void requestNotificationPermission();
  }, [notif]);

  // Nothing worth painting until the account's settings are in force; see the
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { formatAddress, initials, isValidEmail, parseAddressList, parseMailto } from "../address";
+import { displayName, formatAddress, initials, isValidEmail, parseAddressList, parseMailto } from "../address";

 describe("address parsing", () => {
  it("parses mixed lists", () => {
@@ -55,3 +55,14 @@ describe("mailto URLs", () => {
    expect(m.to).toHaveLength(1);
  });
 });
+
+describe("names that reorder themselves", () => {
+  const spoof = { name: "[email protected]\u202E", email: "[email protected]" };
+  it("lose their direction controls when displayed", () => {
+    expect(displayName({ name: "\u202Egnp.exe\u202C Ann", email: "[email protected]" })).toBe("gnp.exe Ann");
+    expect(formatAddress(spoof)).toBe("[email protected] <[email protected]>");
+  });
+  it("fall back to the address when nothing else is left", () => {
+    expect(displayName({ name: "\u200F\u202E", email: "[email protected]" })).toBe("[email protected]");
+  });
+});
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { contactFromAddress, nameParts } from "../contacts";
+import { contactFromAddress, contactPhoto, nameParts, withPhoto } from "../contacts";
 import type { ContactCard } from "@/jmap/types";

 const parts = (name: string | null, email = "[email protected]") =>
@@ -34,3 +34,35 @@ describe("contactFromAddress", () => {
    expect(contactFromAddress({ name: "   ", email: "[email protected]" }).name).toBeUndefined();
  });
 });
+
+/**
+ * #376: a photo saved as a `blobId` was refused by Stalwart, which only takes
+ * the `uri` form. Saving one must also leave a card's other media alone.
+ */
+describe("withPhoto", () => {
+  const photo = { dataUrl: "data:image/jpeg;base64,AAAA", type: "image/jpeg" };
+
+  it("puts the photo in as a data URI, never a blob id", () => {
+    const media = withPhoto(undefined, photo)!;
+    const [m] = Object.values(media);
+    expect(m).toEqual({ "@type": "Media", kind: "photo", uri: photo.dataUrl, mediaType: "image/jpeg" });
+    expect(m).not.toHaveProperty("blobId");
+  });
+
+  it("replaces an existing photo and keeps a logo", () => {
+    const media = withPhoto({ old: { kind: "photo", blobId: "b1" }, l: { kind: "logo", uri: "data:image/png;base64,BB" } }, photo)!;
+    expect(Object.values(media).filter((m) => m.kind === "photo")).toHaveLength(1);
+    expect(media.old).toBeUndefined();
+    expect(media.l).toEqual({ kind: "logo", uri: "data:image/png;base64,BB" });
+  });
+
+  it("removes only the photo, and clears media when nothing is left", () => {
+    expect(withPhoto({ p: { kind: "photo", uri: "data:x" }, s: { kind: "sound", uri: "data:y" } }, null)).toEqual({ s: { kind: "sound", uri: "data:y" } });
+    expect(withPhoto({ p: { kind: "photo", uri: "data:x" } }, null)).toBeNull();
+  });
+
+  it("is read back by contactPhoto", () => {
+    const card = { id: "c1", media: withPhoto(undefined, photo) } as unknown as ContactCard;
+    expect(contactPhoto(card, "a1")).toBe(photo.dataUrl);
+  });
+});
@@ -6,8 +6,8 @@
 * the joining is Intl's rather than a hardcoded " and ".
 */
 import { describe, expect, it } from "vitest";
-import { describeRule as describeSieve } from "../sieve";
-import { describeRule as describeRecurrence, weekdayOptions } from "../recurrence";
+import { describeRule as describeSieve } from "../sieve/sieve";
+import { describeRule as describeRecurrence, weekdayOptions } from "../calendar/recurrence";
 import { setUiLanguageForFormatting } from "../datetime";
 import { setCatalog } from "../i18n";

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { hasHtmlAlternative } from "../html";
+import { hasHtmlAlternative } from "../text/html";

 /*
 * The rule: `htmlBody` is derived, so its presence proves nothing. Only the
@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, it, vi } from "vitest";
-import { isTextEntry, keyboard } from "@/lib/keyboard";
+import { isTextEntry, keyboard } from "@/lib/input/keyboard";

 /*
 * Shortcuts after a click on a checkbox (#260).
@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, it, vi } from "vitest";
-import { comboOf, keyboard } from "@/lib/keyboard";
+import { comboOf, keyboard } from "@/lib/input/keyboard";

 /*
 * A "keydown" that carries no key. Chrome's password autofill dispatches one
@@ -1,5 +1,5 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
-import { keyboard } from "@/lib/keyboard";
+import { keyboard } from "@/lib/input/keyboard";

 /*
 * Two-key sequences against the single keys they start with.
@@ -1,6 +1,6 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { collectShare, shareBody, SHARE_MAX_AGE_MS } from "@/lib/shareTarget";
-import { SW_CACHE_NAME } from "@/lib/swCache";
+import { SW_CACHE_NAME } from "@/lib/sw/swCache";

 /**
 * The handoff, from the tab's side. The worker's half cannot be exercised here
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { navSwipeThreshold, swipeNavDirection, swipeThreshold, lockAxis } from "@/lib/touch";
+import { navSwipeThreshold, swipeNavDirection, swipeThreshold, lockAxis } from "@/lib/input/touch";

 describe("navSwipeThreshold", () => {
  it("asks for more travel than a row swipe does, at every width", () => {
@@ -79,6 +79,12 @@ describe("isTnef", () => {
 });

 describe("parseTnef", () => {
+  it("takes the direction overrides out of a name", () => {
+    const out = parseTnef(tnef(file("x.bin", "MZ", [
+      { id: ATT.attachment, data: mapi([{ id: 0x3707, type: 0x001f, value: "Invoice_\u202Efdp.exe" }]) },
+    ])));
+    expect(out[0]!.name).toBe("Invoice_fdp.exe");
+  });
  it("pulls one attachment out, with its name and bytes", () => {
    const out = parseTnef(tnef(file("report.pdf", "hello")));
    expect(out).toHaveLength(1);
@@ -1,4 +1,5 @@
 import type { EmailAddress } from "@/jmap/types";
+import { withoutBidiControls } from "@/lib/text/text";

 const EMAIL_RE = /^[^\s@<>"',;]+@[^\s@<>"',;]+\.[^\s@<>"',;]+$/;

@@ -48,9 +49,10 @@ export function parseOne(raw: string): EmailAddress | null {

 export function formatAddress(a: EmailAddress | null | undefined): string {
  if (!a) return "";
-  if (!a.name) return a.email;
-  const needsQuote = /[,;<>"()\\]/.test(a.name);
-  const name = needsQuote ? `"${a.name.replace(/(["\\])/g, "\\$1")}"` : a.name;
+  const clean = a.name ? withoutBidiControls(a.name) : "";
+  if (!clean) return a.email;
+  const needsQuote = /[,;<>"()\\]/.test(clean);
+  const name = needsQuote ? `"${clean.replace(/(["\\])/g, "\\$1")}"` : clean;
  return `${name} <${a.email}>`;
 }

@@ -60,7 +62,8 @@ export function formatAddressList(list: EmailAddress[] | null | undefined): stri

 export function displayName(a: EmailAddress | null | undefined, fallback = "(unknown)"): string {
  if (!a) return fallback;
-  if (a.name?.trim()) return a.name.trim();
+  const name = a.name ? withoutBidiControls(a.name).trim() : "";
+  if (name) return name;
  return a.email || fallback;
 }

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { ADMIN_BASELINE, adminSections, can, dashboardCards, canGrantRole, generatePassword, hasAdministration, outranks, permissionSet, resolveRoles, type RoleDef } from "@/lib/adminAccess";
+import { ADMIN_BASELINE, adminSections, can, dashboardCards, canGrantRole, generatePassword, hasAdministration, outranks, permissionSet, resolveRoles, type RoleDef } from "@/lib/admin/adminAccess";

 const set = (...p: string[]) => permissionSet(p);
 const everything = set(...ADMIN_BASELINE, "sysTenantGet", "jmapEmailGet", "impersonate");
@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { client, JmapMethodError } from "@/jmap/client";
-import { balancedColumns, countObjects, isRefused, loadMetrics, summarizeMetrics, type MetricRecord } from "@/lib/adminDashboard";
+import { balancedColumns, countObjects, isRefused, loadMetrics, summarizeMetrics, type MetricRecord } from "@/lib/admin/adminDashboard";

 const counter = (metric: string, count: number, timestamp = "2026-09-15T14:00:00Z"): MetricRecord => ({ "@type": "Counter", metric, count, timestamp });

@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { client } from "@/jmap/client";
-import { aliasList, describeDirectoryError, DirectoryError, hasPassword, passwordPatch, queryAccounts, quotasWithDisk } from "@/lib/adminDirectory";
+import { aliasList, describeDirectoryError, DirectoryError, hasPassword, passwordPatch, queryAccounts, quotasWithDisk } from "@/lib/admin/adminDirectory";

 describe("setting a password", () => {
  it("writes into the existing password credential, keeping its place", () => {
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { describeLinked, dkimAlgorithm, looksLikeDomain, normalizeDomain, parseZoneFile } from "@/lib/adminDomains";
+import { describeLinked, dkimAlgorithm, looksLikeDomain, normalizeDomain, parseZoneFile } from "@/lib/admin/adminDomains";

 /**
 * Written the way Stalwart's BIND serializer writes it (dns-update's
@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { client } from "@/jmap/client";
-import { countMembers, createGroup, destroyGroup, groupRoleKey, groupRolesFromKey, membershipPatch } from "@/lib/adminGroups";
+import { countMembers, createGroup, destroyGroup, groupRoleKey, groupRolesFromKey, membershipPatch } from "@/lib/admin/adminGroups";

 describe("group membership", () => {
  it("is a patch to each member, one pointer each, so no other membership moves", () => {
@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { client } from "@/jmap/client";
-import { createList, parseAddresses, queryLists, recipientsPatch } from "@/lib/adminLists";
+import { createList, parseAddresses, queryLists, recipientsPatch } from "@/lib/admin/adminLists";

 describe("a mailing list's recipients", () => {
  it("are saved as what was added and removed, one pointer each", () => {
@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
-import { permissionSet } from "@/lib/adminAccess";
-import { canBuildOn, effectivePermissions, inherited, roleOutranks, setPatch, type DirectoryRole } from "@/lib/adminRoles";
+import { permissionSet } from "@/lib/admin/adminAccess";
+import { canBuildOn, effectivePermissions, inherited, roleOutranks, setPatch, type DirectoryRole } from "@/lib/admin/adminRoles";

 const flags = (...n: string[]) => Object.fromEntries(n.map((x) => [x, true]));
 const roles = new Map<string, DirectoryRole>([
@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { client } from "@/jmap/client";
-import { countTenantMembers, drawableLogo, quotasPatch, setDomainTenant } from "@/lib/adminTenants";
+import { countTenantMembers, drawableLogo, quotasPatch, setDomainTenant } from "@/lib/admin/adminTenants";

 describe("a tenant's limits", () => {
  it("change one pointer each, leaving the quotas ihasmail does not offer alone", () => {
@@ -1,6 +1,6 @@
 import { client } from "@/jmap/client";
 import { t } from "@/lib/i18n";
-import type { PermissionsMode, RoleDef, UserRoles } from "@/lib/adminAccess";
+import type { PermissionsMode, RoleDef, UserRoles } from "@/lib/admin/adminAccess";

 /**
 * Stalwart 0.16's directory, over the ordinary JMAP proxy.
@@ -1,6 +1,6 @@
 import { client } from "@/jmap/client";
 import { plural, t } from "@/lib/i18n";
-import { DirectoryError } from "@/lib/adminDirectory";
+import { DirectoryError } from "@/lib/admin/adminDirectory";

 /**
 * Stalwart 0.16's domains, over the same proxy as accounts.
@@ -1,7 +1,7 @@
 import { client } from "@/jmap/client";
 import { t } from "@/lib/i18n";
-import type { PermissionsMode, UserRoles } from "@/lib/adminAccess";
-import { DirectoryError, DISK_QUOTA, queryAccounts, type EmailAlias } from "@/lib/adminDirectory";
+import type { PermissionsMode, UserRoles } from "@/lib/admin/adminAccess";
+import { DirectoryError, DISK_QUOTA, queryAccounts, type EmailAlias } from "@/lib/admin/adminDirectory";

 /**
 * Groups, from Stalwart 0.16's directory.
@@ -1,6 +1,6 @@
 import { client } from "@/jmap/client";
 import { t } from "@/lib/i18n";
-import { DirectoryError, type EmailAlias } from "@/lib/adminDirectory";
+import { DirectoryError, type EmailAlias } from "@/lib/admin/adminDirectory";

 /**
 * Mailing lists, from Stalwart 0.16's directory.
@@ -1,8 +1,8 @@
 import { apiFetch, client } from "@/jmap/client";
 import { t } from "@/lib/i18n";
-import type { Permissions, RoleDef } from "@/lib/adminAccess";
-import { DirectoryError } from "@/lib/adminDirectory";
-import { DomainError } from "@/lib/adminDomains";
+import type { Permissions, RoleDef } from "@/lib/admin/adminAccess";
+import { DirectoryError } from "@/lib/admin/adminDirectory";
+import { DomainError } from "@/lib/admin/adminDomains";
 import type { PermissionInfo } from "@/lib/permissionLabels";

 /**
@@ -1,7 +1,7 @@
 import { client } from "@/jmap/client";
 import { t } from "@/lib/i18n";
-import { DirectoryError } from "@/lib/adminDirectory";
-import { DomainError } from "@/lib/adminDomains";
+import { DirectoryError } from "@/lib/admin/adminDirectory";
+import { DomainError } from "@/lib/admin/adminDomains";

 /**
 * Tenants, from Stalwart 0.16's directory.
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { appointmentDraft, nextHalfHour } from "@/lib/appointment";
+import { appointmentDraft, nextHalfHour } from "@/lib/calendar/appointment";
 import type { Email, EmailBodyPart } from "@/jmap/types";

 /**
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { availabilityWindow } from "@/lib/availabilityWindow";
+import { availabilityWindow } from "@/lib/calendar/availabilityWindow";

 const at = (s: string) => new Date(s);
 const hours = (w: { ticks: { time: Date }[] }) => w.ticks.map((t) => `${t.time.getDate()}@${t.time.getHours()}`);
@@ -13,7 +13,7 @@ import {
  dayDelta,
  resizePatch,
  SNAP_MINUTES,
-} from "@/lib/eventDrag";
+} from "@/lib/calendar/eventDrag";
 import { BIRTHDAY_ID_PREFIX } from "@/lib/birthdays";
 import type { CalendarEvent } from "@/jmap/types";

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { looksLikeCalendar, parseIcs, parseIcsDuration, parseDateValue, parseLine, unescapeText, unfold } from "@/lib/ics";
+import { looksLikeCalendar, parseIcs, parseIcsDuration, parseDateValue, parseLine, unescapeText, unfold } from "@/lib/calendar/ics";

 const cal = (body: string) => `BEGIN:VCALENDAR\r\nVERSION:2.0\r\n${body}\r\nEND:VCALENDAR\r\n`;
 const event = (props: string) => `BEGIN:VEVENT\r\n${props}\r\nEND:VEVENT`;
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { toIcs, parseIcs } from "@/lib/ics";
+import { toIcs, parseIcs } from "@/lib/calendar/ics";
 import type { JSCalendarEvent } from "@/jmap/types";

 /*
@@ -1,9 +1,9 @@
 import type { Email, EmailAddress } from "@/jmap/types";
 import { useCalendar, type EventDraft } from "@/store/calendar";
 import { useMail } from "@/store/mail";
-import { uniqueAddresses } from "./address";
-import { toLocalDateOnly } from "./dates";
-import { htmlToText } from "./text";
+import { uniqueAddresses } from "../address";
+import { toLocalDateOnly } from "../dates";
+import { htmlToText } from "../text/text";

 /**
 * How much of a message body is copied into an event description.
@@ -10,8 +10,8 @@
 * question — given an event and a gesture, what are the new start and end —
 * and the caller decides whether it is allowed to save that.
 */
-import { addMinutes } from "./dates";
-import { isBirthdayEvent } from "./birthdays";
+import { addMinutes } from "../dates";
+import { isBirthdayEvent } from "../birthdays";
 import type { CalendarEvent } from "@/jmap/types";

 /**
@@ -1,5 +1,5 @@
 import type { JSCalendarRecurrenceRule, JSCalendarNDay } from "@/jmap/types";
-import { formatList, weekdayName, weekdayNames } from "./datetime";
+import { formatList, weekdayName, weekdayNames } from "../datetime";
 import { plural, t } from "@/lib/i18n";

 /**
@@ -1,4 +1,4 @@
-import type { ContactCard, EmailAddress, JSContactName } from "@/jmap/types";
+import type { ContactCard, EmailAddress, JSContactMedia, JSContactName } from "@/jmap/types";
 import { withBase } from "@/lib/basePath";

 /** Best display name for a card. */
@@ -57,6 +57,22 @@ export function contactEmails(c: ContactCard): EmailAddress[] {
  return Object.values(c.emails ?? {}).map((e) => ({ name: name.includes("@") ? null : name, email: e.address }));
 }

+/**
+ * A card's `media` with its photo replaced by `photo`, or removed when that is
+ * null, and everything else in it -- a logo, a sound -- left as it was.
+ *
+ * The photo goes in as a `data:` URI. Stalwart (0.16.22, checked live on
+ * 2026-09-16) refuses a `blobId` in `media` outright -- "blobIds in media is
+ * not supported" -- which is RFC 9610's JMAP extension to JSContact, and
+ * accepts the plain RFC 9553 `uri` form, returning it unchanged (#376). The
+ * editor's photo is a 256px JPEG, tens of kilobytes; 134 KB was accepted.
+ */
+export function withPhoto(media: Record<string, JSContactMedia> | undefined | null, photo: { dataUrl: string; type: string } | null): Record<string, JSContactMedia> | null {
+  const rest: Record<string, JSContactMedia> = Object.fromEntries(Object.entries(media ?? {}).filter(([, m]) => m.kind !== "photo"));
+  if (photo) rest[newKey("p")] = { "@type": "Media", kind: "photo", uri: photo.dataUrl, mediaType: photo.type };
+  return Object.keys(rest).length ? rest : null;
+}
+
 export function contactPhoto(c: ContactCard, accountId: string): string | null {
  const m = Object.values(c.media ?? {}).find((x) => x.kind === "photo");
  if (!m) return null;
@@ -0,0 +1,16 @@
+/**
+ * Hand the browser a file the app made, to save.
+ *
+ * The object URL is released as soon as the download has been started: a
+ * click on the link starts it synchronously, and an unreleased URL keeps the
+ * whole file in memory for as long as the tab is open -- an address book's
+ * worth of vCards, per export.
+ */
+export function downloadFile(content: BlobPart, type: string, filename: string): void {
+  const url = URL.createObjectURL(new Blob([content], { type }));
+  const a = document.createElement("a");
+  a.href = url;
+  a.download = filename;
+  a.click();
+  URL.revokeObjectURL(url);
+}
@@ -9,7 +9,7 @@
 * so a node has one shape and there is nothing left to detect.
 */
 import type { FileNode, Id } from "@/jmap/types";
-import { descendantIds } from "./folderMove";
+import { descendantIds } from "./mailbox/folderMove";

 /** Properties to request for a node. */
 export function fileNodeProps(): string[] {
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { foldersNeeded, hasDirectory, planUpload } from "@/lib/dropUpload";
+import { foldersNeeded, hasDirectory, planUpload } from "@/lib/input/dropUpload";

 /**
 * Dropping a folder in, reduced to the two things the DataTransfer entry API
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { rowClick, type RowClick } from "@/lib/listSelection";
+import { rowClick, type RowClick } from "@/lib/input/listSelection";

 const IDS = ["a", "b", "c", "d", "e"];
 const click = (over: Partial<Parameters<typeof rowClick>[0]> = {}): RowClick =>
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { archiveSegments, archivePath, groupByArchivePath } from "@/lib/archiveDate";
+import { archiveSegments, archivePath, groupByArchivePath } from "@/lib/mailbox/archiveDate";

 /**
 * The dates below are written as local-time strings on purpose. The segments
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { canEmpty, emptyLabel } from "@/lib/emptyFolder";
+import { canEmpty, emptyLabel } from "@/lib/mailbox/emptyFolder";
 import type { MailboxRole } from "@/jmap/types";

 /**
--- a/Show More
+++ b/Show More