anonymous telemetry

README.md

@@ -106,6 +106,13 @@ inference when available, falling back to WASM otherwise. The desktop app
 bundles Chromium via Electron and sets the same isolation headers on its
 `app://` protocol.
 
+## Telemetry
+
+By default, Rescript reports anonymous usage stats so we can tell how many people actually
+use it and which features are worth the maintenance. You
+can turn it off in **Settings → Privacy → Anonymous usage stats**, which stops
+it immediately and permanently on that install.
+
 ## License
 
 Copyright (c) 2026 Wassim Gharbi and Rescript contributors.

components/Editor.tsx

@@ -7,6 +7,7 @@ import { getCutRanges, isWordCutOut } from "@/lib/edits";
 import { extractAudio, getFFmpeg } from "@/lib/ffmpeg";
 import { VAD_SAMPLE_RATE } from "@/lib/vad";
 import { isElectron } from "@/lib/platform";
+import { trackEvent } from "@/lib/telemetry";
 import { useIsDesktopLayout } from "@/hooks/useIsDesktopLayout";
 import { useTranscriber } from "@/hooks/useTranscriber";
 import TopBar from "./TopBar";
@@ -135,6 +136,11 @@ export default function Editor() {
   const [modeTransitioning, setModeTransitioning] = useState(false);
   const wasIdle = useRef(status === "idle");
 
+  // Daily-active signal. trackEvent guards against Strict Mode's double effect.
+  useEffect(() => {
+    trackEvent("app_opened");
+  }, []);
+
   // Processing pipeline: load ffmpeg -> extract audio -> (maybe) transcribe.
   // Restored projects already have words; they only need PCM for the waveform.
   const startedFor = useRef<File | null>(null);

components/ExportDialog.tsx

@@ -10,6 +10,7 @@ import {
   X,
 } from "lucide-react";
 import { useEditorStore } from "@/lib/store";
+import { trackEvent } from "@/lib/telemetry";
 import { formatTime, getEditedDuration, getKeepRanges } from "@/lib/edits";
 import {
   exportAudio,
@@ -190,6 +191,11 @@ export default function ExportDialog() {
       const prev = useEditorStore.getState().exportUrl;
       if (prev) URL.revokeObjectURL(prev);
       setExportUrl(URL.createObjectURL(blob));
+      trackEvent("export_completed", {
+        kind: activeTab,
+        format: activeTab === "audio" ? audioFormat : videoFormat,
+        ...(activeTab === "audio" ? {} : { resolution }),
+      });
     } catch (err) {
       setError(err instanceof Error ? err.message : "Export failed.");
     } finally {
@@ -221,6 +227,7 @@ export default function ExportDialog() {
           speakers,
         });
         setError(null);
+        trackEvent("export_completed", { kind, format });
       } catch (err) {
         setError(err instanceof Error ? err.message : "Export failed.");
       }

components/SettingsMenu.tsx

@@ -11,6 +11,7 @@ import {
   X_PROFILE_URL,
 } from "./SocialLinks";
 import { useAppearance } from "@/hooks/useAppearance";
+import { useTelemetryPref } from "@/hooks/useTelemetryPref";
 import Popover, { PopoverContent, PopoverTrigger } from "./Popover";
 import type { Appearance } from "@/lib/theme";
 
@@ -33,6 +34,7 @@ export default function SettingsMenu() {
   const [open, setOpen] = useState(false);
   const panelId = useId();
   const { appearance, setAppearance } = useAppearance();
+  const { enabled: telemetry, setEnabled: setTelemetry } = useTelemetryPref();
 
   return (
     <Popover
@@ -89,7 +91,7 @@ export default function SettingsMenu() {
             </div>
           </section>
 
-          <section className="py-1.5">
+          <section className="border-b border-zinc-100 px-1.5 py-1.5 dark:border-zinc-800">
             {MENU_LINKS.map(({ label, href, Icon }) => (
               <a
                 key={label}
@@ -113,6 +115,29 @@ export default function SettingsMenu() {
               </a>
             ))}
           </section>
+
+          <section className="px-2 py-2.5">
+            <p className="mb-2 text-[11px] font-medium tracking-wide text-zinc-400 dark:text-zinc-500">
+              Privacy
+            </p>
+            <label className="flex cursor-pointer items-start gap-2.5">
+              <input
+                type="checkbox"
+                checked={telemetry}
+                onChange={(e) => setTelemetry(e.target.checked)}
+                className="mt-0.5 h-3.5 w-3.5 shrink-0 cursor-pointer accent-transparent"
+              />
+              <span>
+                <span className="block text-[12px] text-zinc-700 dark:text-zinc-300">
+                  Help improve the app
+                </span>
+                <span className="mt-0.5 block text-[11px] leading-snug text-zinc-400 dark:text-zinc-500">
+                  Send anonymous usage statistics (nothing about your media).
+                </span>
+              </span>
+            </label>
+          </section>
+
         </PopoverContent>
       </div>
     </Popover>

hooks/useTelemetryPref.ts

@@ -0,0 +1,19 @@
+"use client";
+
+import { useCallback, useState } from "react";
+import { isTelemetryEnabled, setTelemetryEnabled } from "@/lib/telemetry";
+
+/**
+ * Anonymous usage telemetry preference (default on, opt-out). Safe to read in
+ * the initializer because the whole editor tree is client-only (`ssr: false`).
+ */
+export function useTelemetryPref() {
+  const [enabled, setEnabledState] = useState(() => isTelemetryEnabled());
+
+  const setEnabled = useCallback((next: boolean) => {
+    setTelemetryEnabled(next);
+    setEnabledState(next);
+  }, []);
+
+  return { enabled, setEnabled };
+}

hooks/useTranscriber.ts

@@ -3,6 +3,7 @@
 import { useCallback, useEffect, useRef } from "react";
 import { isModelId } from "@/lib/models";
 import { useEditorStore } from "@/lib/store";
+import { trackEvent } from "@/lib/telemetry";
 import type { WorkerResponse } from "@/lib/types";
 
 let activeWorker: Worker | null = null;
@@ -58,6 +59,12 @@ export function useTranscriber() {
           s.setWords(msg.words);
           s.setStatus("ready");
           s.setPartialText("");
+          // Which model and language actually get used, to prioritise backends.
+          // Nothing about the media itself — not its length, not the text.
+          trackEvent("transcription_completed", {
+            model,
+            language: transcriptLanguage,
+          });
           break;
         case "error":
           s.setError(msg.message);

lib/store.ts

@@ -28,6 +28,7 @@ import {
 } from "./edits";
 import { isModelId, loadModelPreference, saveModelPreference } from "./models";
 import { isTranscriptSource, type TranscriptSource } from "./source";
+import { trackEvent } from "./telemetry";
 import {
   DEFAULT_TRANSCRIPT_LANGUAGE,
   isTranscriptLanguage,
@@ -371,6 +372,12 @@ export const useEditorStore = create<EditorState>((set, get) => ({
       audio: null,
       duration: 0,
     });
+    // Funnel step between opening the app and getting a transcript. `kind` and
+    // `source` are fixed vocabulary — nothing derived from the file itself.
+    trackEvent("project_created", {
+      kind,
+      source: imported ? "import" : "asr",
+    });
   },
 
   openProject: async (id) => {

lib/telemetry.ts

@@ -0,0 +1,131 @@
+"use client";
+
+import { isElectron } from "./platform";
+
+/**
+ * Anonymous usage telemetry — how many installs are active, and how far they get
+ * through the pipeline. Deliberately not an analytics SDK and deliberately not
+ * an account:
+ *
+ * - The only identifier is a random UUID this module generates for itself. It is
+ *   not derived from the machine, the network, or the person, and clearing site
+ *   data resets it.
+ * - Nothing about the user's media is ever sent — no filenames, no durations, no
+ *   transcript text. The `props` below are fixed vocabulary (model id, export
+ *   format) chosen so that no field can carry user content.
+ * - Fire-and-forget. Nothing awaits these calls, failures are swallowed, and
+ *   offline is a silent no-op, so the editor behaves identically with telemetry
+ *   on, off, or unreachable. That matters: the app is meant to work with the
+ *   network cable pulled.
+ *
+ * Opt-out lives in Settings and is honoured before any of this runs.
+ */
+
+const ENDPOINT =
+  process.env.NEXT_PUBLIC_TELEMETRY_ENDPOINT ??
+  "https://www.getrescript.com/api/telemetry";
+
+const INSTALL_ID_KEY = "rescript.installId";
+const ENABLED_KEY = "rescript.telemetry";
+
+export type TelemetryEvent =
+  | "app_opened"
+  | "project_created"
+  | "transcription_completed"
+  | "export_completed";
+
+type Props = Record<string, string | number | boolean>;
+
+/** localStorage throws in private-mode Safari and when storage is full. */
+function read(key: string): string | null {
+  try {
+    return localStorage.getItem(key);
+  } catch {
+    return null;
+  }
+}
+
+function write(key: string, value: string) {
+  try {
+    localStorage.setItem(key, value);
+  } catch {
+    // Preference just won't persist; not worth surfacing.
+  }
+}
+
+/** Opt-out, so an unset value means enabled. */
+export function isTelemetryEnabled(): boolean {
+  if (typeof window === "undefined") return false;
+  return read(ENABLED_KEY) !== "off";
+}
+
+export function setTelemetryEnabled(enabled: boolean) {
+  write(ENABLED_KEY, enabled ? "on" : "off");
+}
+
+function installId(): string | null {
+  const existing = read(INSTALL_ID_KEY);
+  if (existing) return existing;
+  // No crypto.randomUUID on http:// origins or very old browsers. Rather than
+  // fall back to a weaker id, skip reporting — a missing install is a better
+  // failure than a colliding one.
+  if (typeof crypto?.randomUUID !== "function") return null;
+  const id = crypto.randomUUID();
+  write(INSTALL_ID_KEY, id);
+  // If persisting failed the id is per-session, which inflates install counts
+  // slightly. Accepted: the alternative is fingerprinting.
+  return id;
+}
+
+function platform(): "macos" | "windows" | "linux" | "unknown" {
+  const ua = navigator.userAgent;
+  if (/mac os x|macintosh/i.test(ua)) return "macos";
+  if (/windows/i.test(ua)) return "windows";
+  if (/linux|x11|cros/i.test(ua)) return "linux";
+  return "unknown";
+}
+
+/** Guards `app_opened` against React remounts and Strict Mode double-effects. */
+let openedReported = false;
+
+export function trackEvent(event: TelemetryEvent, props?: Props) {
+  if (typeof window === "undefined") return;
+  if (event === "app_opened") {
+    if (openedReported) return;
+    openedReported = true;
+  }
+  if (!isTelemetryEnabled()) return;
+
+  const id = installId();
+  if (!id) return;
+
+  const body = JSON.stringify({
+    installId: id,
+    event,
+    version: process.env.NEXT_PUBLIC_APP_VERSION,
+    platform: platform(),
+    surface: isElectron ? "desktop" : "web",
+    props: props ?? null,
+  });
+
+  if (process.env.NODE_ENV !== "production") {
+    console.debug("[telemetry]", event, props ?? {});
+    return;
+  }
+
+  try {
+    void fetch(ENDPOINT, {
+      method: "POST",
+      // Survives the export-then-close case, where the tab may go away before
+      // the request settles.
+      keepalive: true,
+      mode: "cors",
+      // No cookies, ever — this endpoint has nothing to authenticate.
+      credentials: "omit",
+      headers: { "Content-Type": "application/json" },
+      body,
+    }).catch(() => {});
+  } catch {
+    // Offline, blocked by an extension, or CSP — all fine, all ignored.
+  }
+}

next.config.ts

@@ -1,5 +1,13 @@
+import { readFileSync } from "node:fs";
 import type { NextConfig } from "next";
 
+// Telemetry reports which version is in use, so the client needs the version at
+// build time. Read from package.json rather than duplicated in a constant that
+// `npm version` would silently leave stale.
+const { version } = JSON.parse(
+  readFileSync(new URL("./package.json", import.meta.url), "utf8")
+) as { version: string };
+
 // STATIC_EXPORT=1 emits the static bundle shipped to both targets: the web app
 // at app.getrescript.com (served by Vercel, which sends the cross-origin
 // isolation headers from vercel.json) and the Electron shell (which sets them
@@ -9,6 +17,9 @@ const isExport = process.env.STATIC_EXPORT === "1";
 
 const nextConfig: NextConfig = {
   reactStrictMode: true,
+  // Inlined into the client bundle at build time (both targets are static, so
+  // there is no runtime env to read this from).
+  env: { NEXT_PUBLIC_APP_VERSION: version },
   // parakeet.js ships as raw ESM from src/; transpile for the worker bundle.
   transpilePackages: ["parakeet.js"],
   ...(isExport