Claude Design / Artifacts → 4K/60 MP4 (open source, MIT, built with Claude Code)

Hey all — sharing a small tool I open-sourced this morning. The problem: I kept building animated videos inside Claude Design / Claude Artifacts (the React-based <Stage> timeline ones) and every time I needed to ship one as an actual video file I'd end up screen-recording it. Dropped frames, jittery cursor, wrong resolution, no clean audio mux. So I built the missing piece. What it does You drop a Stage-based Claude design project folder in (drag-drop web UI or CLI). It spins up a headless Chromium, scrubs the <Stage> timeline frame by frame at 2× supersampled 4K, and pipes everything through a bundled ffmpeg into an H.264 MP4 at 60fps. Because every frame is a deterministic seek of the timeline (not a real-time capture), there are zero dropped frames — same input always produces the same bytes out. Highlights \- 4K/60 default, 1080p/30 also supported \- Drag-and-drop UI on localhost:4747, plus a CLI for scripting \- Batch mode — drop a parent folder, get…