* feat(cli): download Parakeet with models install parakeet and transcribe with it `hyperframes models install parakeet` installs the sherpa-onnx runtime from npm and the Parakeet TDT 0.6B v3 int8 model from Hugging Face, pinned to a revision. Every file is checked against its pinned size and sha256 under a temp name before it is renamed into place. Re-running it is a no-op. On Linux with glibc older than 2.32 it refuses up front. `transcribe --engine auto|parakeet` now prefers that engine when it is installed, then an installed parakeet-mlx runner, then whisper. Audio is cut into about 60 s windows at the quietest 100 ms near each cut, and decoding runs in a child process. If the child cannot load the runtime or crashes, transcribe falls back with one stderr line saying why. The JSON output and transcript.json shape are unchanged. * fix(skills): report the real word count and engine from transcribe fallbacks The media-use transcribe script read `words` from the CLI's transcript, which is a flat array, so its whisper path always reported an undefined word count. The embedded-captions script labelled every CLI transcript whisper.cpp even when `--engine auto` ran Parakeet; it now uses the engine the CLI reports. * fix(cli): pin the sherpa-onnx native package to the runtime's exact version * test(cli): type the sherpa install test doubles * fix(cli): transcribe audio with no speech as 0 words instead of failing Parakeet writes an empty word list for a music bed, a silent intro or a very short clip, and loading it failed with "Unrecognized JSON transcript format". An empty list is now read as a transcript with no words, as whisper's empty output already is. A non-empty list still has to look like words. * fix(cli): re-decode a Parakeet window that skipped the start of its speech At some window lengths the model silently drops the first clause: on a looped speech clip, 4 of 167 lengths between 55 and 60 s, and a 61.91 s window, lost their first 9 words. A window with a token gap of at least 1 s that is as loud as speech is decoded again with 0.5 s of leading silence, and the result with more tokens wins. Clean windows are unchanged. Decoding with 1.5 s of overlap before each cut was measured too and was worse on 573 s of audio (2.62% WER against 0.98%), so it is not used. Empty audio no longer makes a zero-length window, which aborted the decoder. * fix(cli): stop Parakeet on Ctrl-C and name the repair when its install breaks - Ctrl-C during a Parakeet transcribe now stops with exit 130 instead of starting whisper, and a SIGTERM to the CLI also stops its decode child. - Ctrl-C during models install parakeet aborts the download and the npm install, keeps no partial file, and exits 130. A staging dir left by a killed install is swept by the next run. - When Parakeet fails under --engine auto, the warning leads with the Parakeet error and names hyperframes models install parakeet. If the fallback fails too, the Parakeet error is reported rather than whisper_unavailable, so --optional no longer hides a broken install. - An explicit --engine parakeet no longer falls back: it fails with the Parakeet error and the repair command. - The install refuses up front on systems with no native package (naming the six supported ones) and on musl, instead of a raw npm error. - 24-bit and float WAV go through ffmpeg, since sherpa-onnx reads only 16-bit PCM. The decode timeout scales with the audio length. * docs(cli): point Parakeet setup at models install parakeet The transcribe docs and the media-use references named parakeet-mlx as the only way to get Parakeet. They now name hyperframes models install parakeet, and the CLI reference gets a models section. * test(cli): cover the npm cancel signal and decode timeout, and fix a doubled period The Parakeet failure line printed "failed.. To repair" when the decoder's own message ended in a period. Tests now also pin that Ctrl-C reaches the npm install and that the decode timeout scales with the audio length. * fix(cli): report unreadable audio as an input error, not a Parakeet failure Prepare the WAV once before the Parakeet fallback and hand the same file to whisper, so ffmpeg runs once. Ctrl-C while ffmpeg runs now ends as a cancel (exit 130) instead of starting whisper. * fix(cli): recover a clause Parakeet drops after a pause by decoding the gap alone Each loud gap without tokens is decoded on its own with 0.5 s either side, and only its new tokens are spliced in. The padded whole-window retry stays as the fallback. A window with no tokens at all is no longer decoded twice. * perf(cli): size the decode timeout from the WAV header instead of reading the file * docs(cli): say a broken Parakeet install still fails transcribe --optional * fix(cli): treat Ctrl-C during audio preparation as a cancel and drop the partial WAV ffmpeg traps SIGINT and exits 255 rather than dying by the signal, so that status now counts as a cancel unless the timeout fired. A failed or stopped ffmpeg removes the temp WAV it was writing. The decode timeout now sizes a prepared WAV from its file size, so a large header can no longer hide its length. * fix(cli): splice a re-decoded gap by whole words so its neighbours are never doubled The gap decode splits edge words into other tokens than the window decode did. Match neighbours as whole words within 0.3 s of each gap edge, add only whole words that start inside the gap, and decode the gap behind 0.5 s of silence like the padded retry. * fix(cli): count a cancel only when ffmpeg says it received a signal ffmpeg 7 and later also exit 255 when a file is not permitted (EPERM), so exit 255 alone read a permission error as a cancel. ffmpeg's stderr is now captured, a cancel needs its received-signal line, and any other failure reports ffmpeg's last line. The output path is passed to the shared runner explicitly. * fix(cli): keep a spliced gap word that has no leading space The filter dropped such a word; it is now kept and given its word boundary. * refactor(cli): trim three long comments in the Parakeet decoder and installer * fix(cli): repair a Parakeet runtime missing its native binary, and pick Parakeet by language The runtime dir is per platform and arch. Installed now needs the runtime manifest and the native sherpa-onnx.node; a half-installed dir is removed before npm runs, since install() keeps any dir holding the runtime manifest. The decode worker flattens a multi-line loader error onto its prefixed line and stops between windows once orphaned. transcribe opens its cancellation scope before audio prep, so Ctrl-C under --json cleans up. auto uses Parakeet only for its 25 languages and only where the host can run it; --engine parakeet with another language fails. * fix(cli): sweep reused-pid staging, name failed model downloads, keep ffmpeg's cause sweepStaleStaging also removes a staging dir older than 6 hours whose pid is alive, since containers reuse pids. A failed model download names the file, the host and a retry. runFfmpeg keeps ffmpeg's stderr on its error, so transcribe shows "Output file does not contain any stream" for a video without audio, and reads a cancel only from ffmpeg's own signal line. * fix(skills): make media-use --engine whisper run whisper and report the engine that ran The whisper path now passes --engine whisper when asked, or --engine auto, and reads the engine from the CLI's --json line, so a CLI Parakeet run is no longer labelled whisper. Docs state the language rule, the real repair behaviour and the platforms Parakeet runs on. * test(cli): pin that a long Parakeet decoder error is kept whole up to a bound * fix(cli): report a broken Parakeet runtime with the repair instead of skipping it * refactor(cli): name the staging age limit instead of commenting it * fix(skills): let media-use --engine parakeet use the CLI Parakeet when parakeet-mlx is absent * fix(cli): repair a Parakeet runtime that fails to load, and read Ctrl-C after whisper models install parakeet now loads the runtime in a child process, the way the decode worker does, and reinstalls it when that fails, so a missing shared library, a corrupt binary or missing runtime JS is repaired. It reports changed: false when the runtime loads. transcribe keeps its cheap manifest check. After a failure, transcribe lets the event loop turn once before reading the Ctrl-C scope, since a signal that landed during the synchronous whisper fallback is only handled then. * fix(cli): read Ctrl-C from the whisper child, and re-check the Parakeet runtime after a repair A whisper fallback killed by SIGINT or SIGTERM is a cancel (exit 130), the same rule decode and runFfmpeg use; the loop-turn wait is gone. The runtime probe treats a child stopped by Ctrl-C as a cancel and keeps the runtime; a reinstall is probed again and fails with the loader's error if it still does not load. media-use keeps the CLI's last lines, stdout included, when hyperframes transcribe fails. * fix(cli): give the user-stop rule one owner, SIGHUP included, and end a cancelled install at 130 stoppedByCancelSignal in renderCancellation.ts uses the scope's own signal list (SIGINT, SIGTERM, SIGHUP) and is false whenever Node stopped the child (a code, killed, or a spawn error). decode, runFfmpeg, the runtime probe and the whisper fallback all route through it, so a probe killed by SIGHUP keeps the runtime. isWhisperTimeoutError now keys on ETIMEDOUT only, which Node sets on execFileSync's own timeout, so a SIGTERM reaches the cancel rule. A cancelled models install sets exit 130 and returns instead of failing, and the probe says what went wrong (timed out, crashed, no output). * refactor(cli): let the stop-rule helper name carry its meaning
Write HTML. Render video. Built for agents.
Quickstart | Showcase | Playground | Catalog | Docs | Discord
HyperFrames is an open-source framework for turning HTML, CSS, media, and seekable animations into deterministic MP4 videos. Use it locally with the CLI, from AI coding agents with skills, or as the rendering core behind hosted authoring workflows.
Quick Start
With an AI coding agent
For Claude Code, install the versioned plugin:
claude plugin marketplace add heygen-com/hyperframes
claude plugin install hyperframes@hyperframes
Enable auto-update for the hyperframes marketplace in /plugin → Marketplaces,
then use /hyperframes:hyperframes. See the plugin guide
for Copilot, VS Code, Cursor, Gemini CLI, updates, and migration.
For standalone skills (including OpenCode), use:
npx skills add heygen-com/hyperframes
The picker opens with nothing pre-selected — the Core Skills group is all you need: the
/hyperframesrouter installs each creation workflow on demand. Agents and non-interactive runs should usenpx hyperframes skills updateinstead — it installs exactly the core set, whereasskills add --allinstalls all 21 published skills. The six repo-internal skills under.claude/skills/.agents/skillsare excluded by default. For the full published set usenpx hyperframes skills.
skills addresolves the skills.sh registry blob, which can lagmainby hours.npx hyperframes skills updateinstalls from the currentmain, so reach for it when you need the newest copy of a skill.
Try a prompt like:
Using
/hyperframes, create a 10-second product intro with a fade-in title, a background video, and subtle background music.
The skills teach agents the HyperFrames production loop: plan the video, write valid HTML, wire seekable animations, add media, lint, preview, and render. They work with Claude Code, Codex, Cursor, Gemini CLI, IBM Bob, and other coding agents that support skills.
Skills
HyperFrames ships 21 skills agents load on demand. Read /hyperframes first — it's the router and capability map; it picks a workflow for any "make me a…" request — video, deck, or composition port — and points to the domain skills below.
For standalone installation, default to the core set — the router installs each creation workflow on demand. npx hyperframes skills update installs exactly that from anywhere; the interactive picker (npx skills add heygen-com/hyperframes) lists it as the "Core Skills" group, nothing pre-selected. The picker is interactive-only — a non-interactive or agent run without --skill installs all 21. Use npx skills add heygen-com/hyperframes --all to install the complete published set deliberately (skips the picker), or npx skills add heygen-com/hyperframes --skill <name> for just one (bare name, no leading /).
Standalone installs stay lean after that: npx hyperframes init keeps the core set fresh (the router, the hyperframes-* domain skills, and media-use — plus whatever is already installed; /figma stays on demand) and never expands a partial install; the creation workflows install on demand — the router runs npx hyperframes skills update <workflow> before entering one. Nothing re-pulls the full set behind your back.
Plugin packages
Plugins bundle the full skill catalog and use their agent's update manager.
bun run package:agent-plugin builds the committed portable ZIP, source metadata,
and SHA-256 checksum. See the maintainer checklist.
Upload to Codex
Build the upload-ready Codex plugin archive from the committed HEAD version of the manifest, brand assets, and skills:
bun run package:codex-plugin
This writes dist/hyperframes-plugin.zip with a hyperframes/ root folder and fails if the archive exceeds Codex's 100 MB upload limit.
Router
| Skill | Use when |
|---|---|
/hyperframes |
Read first for any request to make / create / edit / animate / render a video, animation, or motion graphic. Capability map for the domain skills, the intent layer that confirms every creation brief up front, and intent router for the creation workflows below. |
Creation workflows
| Skill | Use when |
|---|---|
/product-launch-video |
Any website — marketing / launching / promoting a product (from its URL, a brief, or a script), or a site tour / showcase / social clip featuring the site's own visuals. Up to ~3 min (sweet spot 30-90s). |
/faceless-explainer |
Explaining a topic / concept from arbitrary text — no product, no URL, no website capture; every visual is LLM-invented (typography / abstract / diagram / data-viz). |
/pr-to-video |
A GitHub pull request (PR URL, owner/repo#N ref, or "this PR") → changelog / feature-reveal / fix / refactor explainer, read via the gh CLI. |
/embedded-captions |
Adding captions / subtitles to an existing talking-head video (footage untouched) — verbatim rail, embedded climax behind the subject, or pure-cinematic embed. |
/talking-head-recut |
Packaging an existing talking-head / interview / podcast video with designed graphic overlays — lower-thirds, data callouts, kinetic titles, pull-quotes, side panels, PiP. |
/motion-graphics |
A short, unnarrated, design-led motion graphic (~under 10s) — kinetic type, stat / chart hit, logo sting, lower-third, animated tweet / headline. MP4 or transparent overlay. |
/music-to-video |
A music track (audio file, video to pull audio from, or one generated from a mood brief) → a beat-synced video — lyric, slideshow, or kinetic promo; music drives pacing. |
/slideshow |
A presentation / pitch deck / interactive deck — discrete slides, fragment reveals, branching, hotspot navigation, presenter mode. Output is a navigable deck, not a rendered video. |
/general-video |
Anything else — longer or multi-scene pieces, brand / sizzle reel, title card, static loop, freeform composition. Input- and length-agnostic fallback, and the home of companion mode (co-create with the full toolbox). |
/remotion-to-hyperframes |
Porting an existing Remotion (React) composition's source to HyperFrames HTML. One-way migration, not creation. |
Domain skills (loaded on demand)
Atomic capabilities the creation workflows compose against — pull one when you need that specific layer.
| Skill | Covers |
|---|---|
/hyperframes-core |
The composition contract — data-* timing attributes, class="clip", tracks, sub-compositions, variables, framework-owned media playback, determinism rules. |
/hyperframes-animation |
All animation knowledge — atomic motion rules, scene blueprints, transitions, runtime adapters (GSAP / Lottie / Three.js / Anime.js / CSS / WAAPI / TypeGPU). |
/hyperframes-keyframes |
Seek-safe keyframe authoring across runtimes — GSAP timelines, CSS keyframes, Anime.js, WAAPI, FLIP, paths, masks, SVG morph/draw, 3D depth — plus hyperframes keyframes diagnostics for rendered motion. |
/hyperframes-creative |
Non-animation creative direction — frame.md / design.md, palettes, typography, narration, beat planning, audio-reactive visuals, composition patterns. |
/media-use |
The media OS — resolve any media need (BGM, SFX, image, icon, logo, voice, color grade, LUT) into a frozen local file or paste-ready block + ledger record, generate via TTS/music/image models when the catalog misses, transcribe, caption, remove backgrounds, and reuse assets across projects. One shared audio engine + manifest tracking. |
/hyperframes-cli |
CLI dev loop — init, lint, check, snapshot, preview, render, publish, doctor, plus HeyGen-hosted cloud rendering (cloud render) and AWS Lambda rendering (lambda deploy / render / progress). |
/hyperframes-audio |
Mix the audio already placed in a composition — voiceover carve (dip a music bed only in the bands the voice occupies, static or dynamic, level match included), the effect chain (EQ, compressor, limiter, gate, saturation, delay, reverb, chorus, phaser, bitcrush), automation envelopes on volume or any effect parameter, and submix buses (<hf-audio-group>) carrying one chain, fader and automation clock for several tracks at once. Sourcing the audio is /media-use. |
/hyperframes-registry |
Search, install and wire registry blocks and components into compositions via hyperframes catalog / hyperframes add. Load before hand-building any named look, effect, treatment or transition. Authoring a new block or component to contribute upstream. |
/figma |
Import Figma assets, tokens, components, and storyboard sections → reconstructed motion (frames read as states, not slides) (REST/CLI) plus Motion animations (MCP) and shaders (MCP source / native export) into a composition. |
For visual design handoff workflows, see the Claude Design guide and Open Design guide.
Manually with the CLI
npx hyperframes init my-video
cd my-video
npx hyperframes preview # preview in browser with live reload
npx hyperframes render # render to MP4
Requirements: Node.js 22+, FFmpeg
What You Can Build
Need ideas? Browse the Showcase for finished videos you can watch, read, run, and remix.
- Product launch videos and feature announcements
- PR walkthroughs with animated code diffs, narration, and captions
- Data visualizations, chart races, and map animations
- Social videos with kinetic captions, overlays, and music
- Docs-to-video, PDF-to-video, and site-tour explainers
- Reusable motion graphics for automated content pipelines
Frame.md
frame.md — your design system, ready for video.
Every brand has a design.md. None of them were written for a camera. frame.md is the missing translation layer: it takes your web-context design spec and inverts it for the frame — the same tokens, the same rules, but rewritten so an AI agent can compose a promo video without guessing at scale or reaching for web chrome.
The output is a DESIGN.md superset your whole toolchain can read. Atoms stay sacred. Composition stays free. Numbers come from the script.
Biennale Yellow |
BlockFrame |
Blue Professional |
Bold Poster |
Broadside |
Capsule |
Cartesian |
Cobalt Grid |
Coral |
Creative Mode |
Browse and remix them all at hyperframes.dev/design.
How It Works
Define a video as HTML. Add data attributes for timing and tracks. Use GSAP, CSS, Lottie, Three.js, Anime.js, WAAPI, or your own frame adapter for seekable animation.
<div id="stage" data-composition-id="launch" data-start="0" data-width="1920" data-height="1080">
<video
class="clip"
data-start="0"
data-duration="6"
data-track-index="0"
src="intro.mp4"
muted
playsinline
></video>
<h1 id="title" class="clip" data-start="1" data-duration="4" data-track-index="1">Launch day</h1>
<audio
data-start="0"
data-duration="6"
data-track-index="2"
data-volume="0.5"
src="music.wav"
></audio>
<script src="https://cdn.jsdelivr.net/npm/gsap@3/dist/gsap.min.js"></script>
<script>
const tl = gsap.timeline({ paused: true });
tl.from("#title", { opacity: 0, y: 40, duration: 0.8 }, 1);
window.__timelines = window.__timelines || {};
window.__timelines.launch = tl;
</script>
</div>
Preview instantly in the browser. Render locally or in Docker. The renderer seeks each frame in headless Chrome and encodes the result with FFmpeg, so the same input produces the same video.
HyperFrames Stack
HyperFrames is the open-source rendering engine, plus a growing set of tools around HTML-native video creation.
| Piece | Status | What it does |
|---|---|---|
| CLI | Available | Scaffold, preview, lint, inspect, and render local video projects |
| Core / Engine / Producer | Available | Parse compositions, drive headless Chrome, encode video, and mix audio |
| Catalog | Available | Reusable blocks and components for transitions, overlays, captions, charts, maps, and effects |
| Agent skills | Available | Teach coding agents the video-production patterns that generic web docs miss |
| Studio | Available, evolving | Browser surface for previewing and editing compositions |
| AWS Lambda rendering | Available | Deploy a distributed render stack and drive renders from your laptop or CI |
| hyperframes.dev | Available | Community playground for previewing, iterating, sharing, and rendering HTML-native video projects |
| frame.md | Available | Invert your design system for the camera — a DESIGN.md superset an agent can compose video from |
Catalog
Install ready-to-use blocks and components:
npx hyperframes add flash-through-white # shader transition
npx hyperframes add instagram-follow # social overlay
npx hyperframes add data-chart # animated chart
Browse the catalog at hyperframes.heygen.com/catalog.
Why HyperFrames?
- HTML-native: compositions are HTML files with data attributes. No React requirement, no proprietary timeline format.
- Agent-friendly: agents already write HTML, and the CLI is non-interactive by default.
- Deterministic: same input, same frames, same output. Built for CI, regression tests, and automated rendering.
- No build step: an
index.htmlcomposition plays as-is and can be previewed directly in the browser. - Adapter-based animation: bring GSAP, CSS animations, Lottie, Three.js, Anime.js, WAAPI, or a custom runtime.
- Open source: Apache 2.0 license, with no per-render fees or commercial-use thresholds.
HyperFrames vs Remotion
HyperFrames is inspired by Remotion. Both tools render video with headless Chrome and FFmpeg. The main difference is the authoring model: Remotion's bet is React components; HyperFrames' bet is plain HTML that humans and agents can both write easily.
| HyperFrames | Remotion | |
|---|---|---|
| Authoring | HTML + CSS + seekable animation | React components |
| Build step | None; index.html plays as-is |
Bundler required |
| Agent handoff | Plain HTML files | JSX / React project |
| Library-clock animations | Seekable, frame-accurate via adapters | Wall-clock animation patterns need care |
| Distributed rendering | Local and AWS Lambda render paths | Remotion Lambda, mature cloud renderer |
| License | Apache 2.0 | Source-available Remotion License |
Read the full comparison in the HyperFrames vs Remotion guide.
Documentation
Full documentation: hyperframes.heygen.com/introduction
Packages
| Package | Description |
|---|---|
hyperframes |
CLI for creating, previewing, linting, and rendering compositions |
@hyperframes/core |
Types, parsers, generators, linter, runtime, and frame adapters |
@hyperframes/engine |
Seekable page-to-video capture engine using Puppeteer and FFmpeg |
@hyperframes/producer |
Full rendering pipeline for capture, encode, and audio mix |
@hyperframes/studio |
Browser-based composition editor UI |
@hyperframes/player |
Embeddable <hyperframes-player> web component |
@hyperframes/shader-transitions |
WebGL shader transitions for compositions |
@hyperframes/aws-lambda |
AWS Lambda SDK and deployment surface for distributed renders |
Community
HyperFrames is used in production at HeyGen, with community examples from teams like tldraw, TanStack, and others in ADOPTERS.md. Open a PR if your team is using HyperFrames.
- Questions and ideas: Discord
- Bugs and feature requests: GitHub Issues
- User research: Book a casual 30-minute conversation with the HyperFrames team — no preparation or sales pitch
- Security reports: SECURITY.md
- Contributions: CONTRIBUTING.md
Development Note
The repo uses Git LFS for golden regression-test baselines under packages/producer/tests/**/output.mp4 (about 240 MB of .mp4 files). If you're cloning the full repo for development, install Git LFS first:
# macOS
brew install git-lfs
# Ubuntu / Debian
sudo apt install git-lfs
# Windows
winget install GitHub.GitLFS
# Then, once per machine
git lfs install
If you only need source files, you can skip LFS content:
GIT_LFS_SKIP_SMUDGE=1 git clone https://github.com/heygen-com/hyperframes.git










