ReplayDeck
Frame-precise YouTube A/B practice tool.
Live · 2025 / 2026 · Personal project
What it is
Free, no-signup YouTube A/B loop practice tool for musicians, dancers, and language learners. Frame-precise markers, timeline zoom, loop memory, stash chains, speed ramping, bookmarks, routines, import / export, PWA behavior, mobile support. Contextual coaching nudges surface from real usage patterns, and production deploys are gated on an end-to-end test suite.
Why I built it this way
Practicing tiny loops in long-form video should feel precise, fast, and local-first instead of clumsy. Bookmarks and stash are intentionally separated as distinct mental models. Splash, motion, and sound calibrated to feel intentional rather than generic.
Implementation and public artifacts
React 19, TypeScript, Vite, Tailwind v4, GSAP, PostHog
replaydeck.comPublished artifacts and reported outcomes have different evidential limits. How to read this portfolio's evidence.