PULSE — Workout Timer

Minimalist body-weight workout timer. Runs entirely in the browser — no server, no account. Inspired by Feeel, built with the help of Claude.

Features

• Trainings — create multiple named workout plans
• Exercises — add from the wger.de database or manually; drag to reorder
• Player — countdown timer with audio beeps, rest phases, "up next" preview
• PWA — installable, works offline, prevents screen from going dark during a session
• Data — stored in localStorage; export/import as JSON

Usage

Open index.html in a browser, or install it as an app via the browser's "Add to Home Screen" prompt.

For full functionality (wger search, service worker, wake lock) serve the files over HTTP/HTTPS — e.g.:

npx serve .
# or
python3 -m http.server

Files

File	Purpose
index.html	Entire app (HTML + CSS + JS)
manifest.json	PWA manifest
icon.svg	App icon (dumbbell)
images/	Exercise illustrations (SVG)
sw.js	Service worker (caching + update flow)
hooks/pre-commit	Git hook: auto-bumps version on commit

License

Code and exercise illustrations © Vitus Schuhwerk, released under the MIT License.

If you use or adapt this project or its images, please keep the license notice. A link back is appreciated but not required.

Versioning

APP_VERSION in index.html and CACHE_NAME in sw.js are auto-bumped (patch) on every commit that touches index.html, via a pre-commit hook. If you bump the version manually before committing, the hook detects the change and skips.

After cloning, enable the hook:

git config core.hooksPath hooks

Screen wake lock

Uses the Screen Wake Lock API to keep the screen on while a workout is running. Supported in Chrome/Edge/Safari 16.4+. Falls back silently on unsupported browsers. Requires HTTPS (or localhost).

Testing

Tests are written using Playwright. Run them with:

bun test
# or
bunx playwright test

Note on seeing console.log output: To keep the AI context window clean, playwright.config.js uses the dot reporter by default. This reporter hides successful test logs. If you need to see console.log output while debugging a passing test, override the reporter:

bunx playwright test --reporter=list

Triggering the built-in update modal (for testing)

When a new version ships with changed built-in trainings, a modal offers to replace your local copies. To simulate this in the browser console:

const s=JSON.parse(localStorage.getItem('pulse_data'));
s.version='0.0.0';
delete s.settings._pendingBuiltinIds;
const v=s.trainings.find(t=>t.builtinId==='vitus-2026');
if(v) v.builtinHash='stale';
localStorage.setItem('pulse_data',JSON.stringify(s));
location.reload();

The modal fires when stored.builtinHash differs from the current builtin fingerprint and state.version doesn't match APP_VERSION. Changing the version alone isn't enough — you also need to fake a stale hash on the training.

Todo

• Remove the full-state backup -> only export trainings -> better merging.
• Should we update default trainings? How implement that simple?