HeyGen's open-source engine that turns HTML + CSS + seekable animation into deterministic MP4 video, rendered with headless Chrome and FFmpeg. This is a self-hosted render service.
Paste a HyperFrames composition (HTML with data-composition-id, data-start, data-duration attributes) and render it to MP4.
POST /render {"html":"<div data-composition-id=...>...</div>"} -> renders, returns the MP4
GET /health
CLI source & docs: github.com/heygen-com/hyperframes (Apache-2.0)