I built Repstack, an open-source fitness app for evidence-based muscle building. It's inspired by Renaissance Periodization's training methodology.

Key features: • 100% offline-first PWA - works without internet, installable on any device • Privacy-first - all data stored locally in IndexedDB, no accounts needed • Science-based - auto-regulation, mesocycle periodization, volume tracking • Free forever - core features will never be paywalled

Tech stack: React 19, TypeScript, Vite, Dexie.js, Workbox

I'm a lifter myself and was frustrated that most fitness apps either require subscriptions, don't work offline, or don't follow evidence-based training principles.

Live demo (installable): https://wulfland.github.io/Repstack/ GitHub: https://github.com/wulfland/Repstack

Looking for feedback on UX and contributors interested in fitness tech. The codebase passes WCAG 2.1 AA accessibility and has comprehensive E2E tests.

What features would you want to see?