feat(notifications): scale completion sound speed with task length

apps/code/src/renderer/desktop-services.ts

@@ -202,6 +202,7 @@ container
  dockBounceNotifications: s.dockBounceNotifications,
  completionSound: s.completionSound,
  completionVolume: s.completionVolume,
+ scaleSoundWithTaskLength: s.scaleSoundWithTaskLength,
  customSounds: s.customSounds,
  };
  },

packages/core/src/sessions/cloudTaskUpdateNotifications.test.ts

@@ -178,6 +178,7 @@ describe("cloud task update notifications", () => {
  "Cloud Task",
  "end_turn",
  TASK_ID,
+ undefined,
  );
  expect(harness.markActivity).toHaveBeenCalledTimes(1);
  });

packages/core/src/sessions/sessionService.ts

@@ -1550,6 +1550,9 @@ export class SessionService {
  session.taskTitle,
  "end_turn",
  session.taskId,
+ session.promptStartedAt
+ ? acpMsg.ts - session.promptStartedAt
+ : undefined,
  );
  }
  this.d.taskViewedApi.markActivity(session.taskId);
@@ -1671,6 +1674,9 @@ export class SessionService {
  session.taskTitle,
  stopReason,
  session.taskId,
+ session.promptStartedAt
+ ? acpMsg.ts - session.promptStartedAt
+ : undefined,
  );
  }
 

packages/ui/src/features/notifications/identifiers.ts

@@ -10,6 +10,7 @@ export interface NotificationSettings {
  dockBounceNotifications: boolean;
  completionSound: CompletionSound;
  completionVolume: number;
+ scaleSoundWithTaskLength: boolean;
  customSounds: CustomSound[];
 }
 

packages/ui/src/features/notifications/notifications.test.ts

@@ -51,6 +51,7 @@ function makeBus(overrides?: {
  dockBounceNotifications: true,
  completionSound: "meep",
  completionVolume: 80,
+ scaleSoundWithTaskLength: false,
  customSounds: [],
  ...overrides?.settings,
  };
@@ -183,4 +184,22 @@ describe("sound", () => {
  bus.notifyPromptComplete("My task", "end_turn", TASK_ID);
  expect(play).toHaveBeenCalledTimes(1);
  });
+
+ it.each([
+ [
+ "scaling off, with duration",
+ false,
+ (10 * 60 * 1000) as number | undefined,
+ 1,
+ ],
+ ["scaling on, quick task (<30s) → 3×", true, 10 * 1000, 3],
+ ["scaling on, no duration → 1×", true, undefined, 1],
+ ])("%s", (_label, scaleSoundWithTaskLength, durationMs, expectedRate) => {
+ const { bus, play } = makeBus({
+ hasFocus: false,
+ settings: { scaleSoundWithTaskLength },
+ });
+ bus.notifyPromptComplete("My task", "end_turn", TASK_ID, durationMs);
+ expect(play).toHaveBeenCalledWith("meep", 80, [], expectedRate);
+ });
 });

packages/ui/src/features/notifications/notifications.ts

@@ -5,7 +5,11 @@ import {
 } from "@posthog/platform/notifications";
 import { toast } from "@posthog/ui/primitives/toast";
 import { openNotificationTarget } from "@posthog/ui/router/navigationBridge";
-import { playCompletionSound, resolveSoundUrl } from "@posthog/ui/utils/sounds";
+import {
+ playbackRateForTaskDuration,
+ playCompletionSound,
+ resolveSoundUrl,
+} from "@posthog/ui/utils/sounds";
 import { inject, injectable } from "inversify";
 import {
  ACTIVE_VIEW_PROVIDER,
@@ -34,6 +38,9 @@ export interface NotificationDescriptor {
  duration?: number;
  };
  silent?: boolean;
+ // How long the task took, in ms. When the user enables sound scaling, this
+ // drives the completion sound's playback rate (fast task -> faster/higher).
+ soundDurationMs?: number;
 }
 
 // The single channel every app notification flows through. Reads focus + the
@@ -61,12 +68,18 @@ export class NotificationBus {
  if (channel === "suppress") return;
 
  const settings = this.settings.get();
+ const playbackRate =
+ settings.scaleSoundWithTaskLength &&
+ descriptor.soundDurationMs !== undefined
+ ? playbackRateForTaskDuration(descriptor.soundDurationMs)
+ : 1;
  // Sound fires on both delivered tiers (toast + native), not on suppress —
  // matching the pre-bus behavior where any non-suppressed notification rang.
  playCompletionSound(
  settings.completionSound,
  settings.completionVolume,
  settings.customSounds,
+ playbackRate,
  );
 
  if (channel === "toast") {
@@ -100,12 +113,14 @@ export class NotificationBus {
  taskTitle: string,
  stopReason: string,
  taskId?: string,
+ durationMs?: number,
  ): void {
  if (stopReason !== "end_turn") return;
  this.notify({
  body: `"${this.truncateTitle(taskTitle)}" finished`,
  target: taskId ? { kind: "task", taskId } : undefined,
  toast: { level: "success" },
+ soundDurationMs: durationMs,
  });
  }
 

packages/ui/src/features/sessions/sessionServiceHost.ts

@@ -84,11 +84,12 @@ function buildSessionServiceDeps(): SessionServiceDeps {
  taskTitle,
  taskId,
  ),
- notifyPromptComplete: (taskTitle, stopReason, taskId) =>
+ notifyPromptComplete: (taskTitle, stopReason, taskId, durationMs) =>
  resolveService(NotificationBus).notifyPromptComplete(
  taskTitle,
  stopReason,
  taskId,
+ durationMs,
  ),
  getIsOnline,
  fetchAuthState,

packages/ui/src/features/settings/sections/NotificationsSettings.tsx

@@ -40,12 +40,14 @@ export function NotificationsSettings() {
  dockBounceNotifications,
  completionSound,
  completionVolume,
+ scaleSoundWithTaskLength,
  customSounds,
  setDesktopNotifications,
  setDockBadgeNotifications,
  setDockBounceNotifications,
  setCompletionSound,
  setCompletionVolume,
+ setScaleSoundWithTaskLength,
  removeCustomSound,
  renameCustomSound,
  } = useSettingsStore();
@@ -117,19 +119,33 @@ export function NotificationsSettings() {
  [completionSound, setCompletionSound],
  );
 
+ const handleScaleSoundChange = useCallback(
+ (checked: boolean) => {
+ track(ANALYTICS_EVENTS.SETTING_CHANGED, {
+ setting_name: "scale_sound_with_task_length",
+ new_value: checked,
+ old_value: scaleSoundWithTaskLength,
+ });
+ setScaleSoundWithTaskLength(checked);
+ },
+ [scaleSoundWithTaskLength, setScaleSoundWithTaskLength],
+ );
+
  const resetToDefaults = useCallback(() => {
  setDesktopNotifications(NOTIFICATION_DEFAULTS.desktopNotifications);
  setDockBadgeNotifications(NOTIFICATION_DEFAULTS.dockBadgeNotifications);
  setDockBounceNotifications(NOTIFICATION_DEFAULTS.dockBounceNotifications);
  setCompletionSound(NOTIFICATION_DEFAULTS.completionSound);
  setCompletionVolume(NOTIFICATION_DEFAULTS.completionVolume);
+ setScaleSoundWithTaskLength(NOTIFICATION_DEFAULTS.scaleSoundWithTaskLength);
  toast.success("Notification settings reset to defaults");
  }, [
  setDesktopNotifications,
  setDockBadgeNotifications,
  setDockBounceNotifications,
  setCompletionSound,
  setCompletionVolume,
+ setScaleSoundWithTaskLength,
  ]);
 
  return (
@@ -270,7 +286,7 @@ export function NotificationsSettings() {
  />
 
  {completionSound !== "none" && (
- <SettingRow label="Sound volume" noBorder>
+ <SettingRow label="Sound volume">
  <Flex align="center" gap="3">
  <Slider
  value={[completionVolume]}
@@ -288,6 +304,20 @@ export function NotificationsSettings() {
  </SettingRow>
  )}
 
+ {completionSound !== "none" && (
+ <SettingRow
+ label="Scale sound speed with task length"
+ description="Play the sound faster for quick tasks and slower for long ones"
+ noBorder
+ >
+ <Switch
+ checked={scaleSoundWithTaskLength}
+ onCheckedChange={handleScaleSoundChange}
+ size="1"
+ />
+ </SettingRow>
+ )}
+
  <NotificationTestHarness
  bus={bus}
  notifications={notifications}

packages/ui/src/features/settings/settingsStore.ts

@@ -113,12 +113,14 @@ interface SettingsStore {
  dockBounceNotifications: boolean;
  completionSound: CompletionSound;
  completionVolume: number;
+ scaleSoundWithTaskLength: boolean;
  customSounds: CustomSound[];
  setDesktopNotifications: (enabled: boolean) => void;
  setDockBadgeNotifications: (enabled: boolean) => void;
  setDockBounceNotifications: (enabled: boolean) => void;
  setCompletionSound: (sound: CompletionSound) => void;
  setCompletionVolume: (volume: number) => void;
+ setScaleSoundWithTaskLength: (enabled: boolean) => void;
  addCustomSound: (sound: CustomSound) => void;
  removeCustomSound: (id: string) => void;
  renameCustomSound: (id: string, name: string) => void;
@@ -187,6 +189,7 @@ export const NOTIFICATION_DEFAULTS = {
  dockBounceNotifications: false,
  completionSound: "none" as CompletionSound,
  completionVolume: 80,
+ scaleSoundWithTaskLength: false,
 };
 
 export const useSettingsStore = create<SettingsStore>()(
@@ -253,6 +256,8 @@ export const useSettingsStore = create<SettingsStore>()(
  set({ dockBounceNotifications: enabled }),
  setCompletionSound: (sound) => set({ completionSound: sound }),
  setCompletionVolume: (volume) => set({ completionVolume: volume }),
+ setScaleSoundWithTaskLength: (enabled) =>
+ set({ scaleSoundWithTaskLength: enabled }),
  addCustomSound: (sound) =>
  set((state) => ({ customSounds: [...state.customSounds, sound] })),
  removeCustomSound: (id) =>
@@ -381,6 +386,7 @@ export const useSettingsStore = create<SettingsStore>()(
  dockBounceNotifications: state.dockBounceNotifications,
  completionSound: state.completionSound,
  completionVolume: state.completionVolume,
+ scaleSoundWithTaskLength: state.scaleSoundWithTaskLength,
  customSounds: state.customSounds,
 
  // Composer / chat

packages/ui/src/utils/sounds.test.ts

@@ -3,7 +3,7 @@ import type {
  CustomSound,
 } from "@posthog/ui/features/settings/settingsStore";
 import { describe, expect, it } from "vitest";
-import { resolveSoundUrl } from "./sounds";
+import { playbackRateForTaskDuration, resolveSoundUrl } from "./sounds";
 
 const customs: CustomSound[] = [
  {
@@ -40,3 +40,23 @@ describe("resolveSoundUrl", () => {
  expect(resolveSoundUrl("custom:gone", customs)).toBeNull();
  });
 });
+
+describe("playbackRateForTaskDuration", () => {
+ it.each([
+ ["below the fast floor (10s)", 10 * 1000, 3],
+ ["at the fast floor (30s)", 30 * 1000, 3],
+ ["geometric mid of the fast ramp (60s)", 60 * 1000, Math.sqrt(3)],
+ ["normal band start (2min)", 2 * 60 * 1000, 1],
+ ["normal band end (4min)", 4 * 60 * 1000, 1],
+ [
+ "geometric mid of the slow ramp",
+ Math.sqrt(4 * 60 * 1000 * (30 * 60 * 1000)),
+ Math.sqrt(1 / 3),
+ ],
+ ["at the slow ceiling (30min)", 30 * 60 * 1000, 1 / 3],
+ ["beyond the slow ceiling (2h)", 2 * 60 * 60 * 1000, 1 / 3],
+ ["NaN (non-finite) → fast rate", Number.NaN, 3],
+ ])("%s → %f", (_label, durationMs, expected) => {
+ expect(playbackRateForTaskDuration(durationMs)).toBeCloseTo(expected, 5);
+ });
+});

packages/ui/src/utils/sounds.ts

@@ -37,6 +37,35 @@ const SOUND_URLS: Record<Exclude<BuiltInCompletionSound, "none">, string> = {
  icq: icqUrl,
 };
 
+const MIN_RATE = 1 / 3;
+const MAX_RATE = 3;
+const FAST_MS = 30 * 1000;
+const NORMAL_START_MS = 2 * 60 * 1000;
+const NORMAL_END_MS = 4 * 60 * 1000;
+const SLOW_MS = 30 * 60 * 1000;
+
+// Maps a task's duration to an audio playback rate so a quick task rings fast
+// (and high-pitched) while a long one drags slow (and low). Anchored at: <=30s
+// -> 3x, the 2-4min "normal" band -> 1x, >=30min -> 1/3x, with smooth
+// log-interpolation across the two ramps so the rate doesn't jump at the edges.
+export function playbackRateForTaskDuration(durationMs: number): number {
+ if (!Number.isFinite(durationMs) || durationMs <= FAST_MS) return MAX_RATE;
+ if (durationMs >= SLOW_MS) return MIN_RATE;
+ if (durationMs >= NORMAL_START_MS && durationMs <= NORMAL_END_MS) return 1;
+
+ if (durationMs < NORMAL_START_MS) {
+ const frac =
+ (Math.log(durationMs) - Math.log(FAST_MS)) /
+ (Math.log(NORMAL_START_MS) - Math.log(FAST_MS));
+ return MAX_RATE ** (1 - frac);
+ }
+
+ const frac =
+ (Math.log(durationMs) - Math.log(NORMAL_END_MS)) /
+ (Math.log(SLOW_MS) - Math.log(NORMAL_END_MS));
+ return MIN_RATE ** frac;
+}
+
 let currentAudio: HTMLAudioElement | null = null;
 
 // Resolves the playable URL for a completion sound: a bundled asset URL for the
@@ -59,6 +88,7 @@ export function playCompletionSound(
  sound: CompletionSound,
  volume = 80,
  customSounds: CustomSound[] = [],
+ playbackRate = 1,
 ): void {
  const url = resolveSoundUrl(sound, customSounds);
  if (!url) return;
@@ -70,6 +100,7 @@ export function playCompletionSound(
 
  const audio = new Audio(url);
  audio.volume = Math.max(0, Math.min(100, volume)) / 100;
+ audio.playbackRate = playbackRate;
  currentAudio = audio;
  audio.play().catch(() => {
  // Audio play can fail if user hasn't interacted with the page yet