OpenLoop is a native macOS app for AI music generation. It runs open models such as ACE-Step 1.5 entirely on your machine: no account, no upload, and the generated files stay on your Mac.
Note
v0.2.2 Alpha. The app is ad-hoc signed and not yet notarized. The pinned ACE-Step runtime can use more than 16 GB of memory even with the Lite model, so Macs with 16 GB or less may swap heavily. 24 GB or more is recommended.
- Projects and Takes. Write a prompt and optional lyrics, then generate one or more Takes per idea.
- Compare and iterate. Switch between two Takes with A/B playback, reproduce a Take from its seed, or create variations.
- Loop and Repaint. Select part of a waveform to loop it, or regenerate only that region.
- History. Search and favorite every generation across Projects.
- Local model management. Install the runtime and Model Packs from Settings, with download sizes and licenses shown up front.
- Scriptable CLI. A headless
openloop-clishares the same library and emits NDJSON for automation.
More screenshots
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- Download the native Alpha DMG from Releases.
- Drag OpenLoop to Applications.
- Open the app and follow the first-time setup to install the engine and a model.
If Gatekeeper blocks the app, see docs/release.md. Upgrading from the earlier Tauri version? Back up your library first; the native app imports it once and leaves your original audio in place.
The CLI ships inside the app bundle:
CLI=/Applications/OpenLoop.app/Contents/MacOS/openloop-cli
"$CLI" setup --accept-license
"$CLI" models install ace-step/standard --accept-license
"$CLI" run --configuration ace-step/lite --prompt 'gentle piano' --duration 10
"$CLI" list --jsonSee the CLI guide and the NDJSON v2 contract.
Requires Apple Silicon, macOS 15+, Swift 6.2+, and Node.js 24+.
swift build --package-path native
swift test --package-path native
node scripts/prepare-sidecars.mjs
python3 native/scripts/package-app.py --uv native/binaries/uv-aarch64-apple-darwinThe app is written to native/dist/OpenLoop.app. See native/README.md
for the architecture and docs/release.md for packaging.
Issues and pull requests are welcome. Please open an issue before a large change. Contributors sign the CLA with a PR comment; see CONTRIBUTING.md.
OpenLoop is licensed under the GNU AGPL-3.0-only. Earlier Apache-2.0 grants remain valid; see LICENSING.md. Models and runtimes keep their own licenses, and generated audio is not guaranteed to be free of copyright claims. Review the model terms before you distribute what you make.
Built on ACE-Step 1.5 and MLX. OpenLoop is part of the OpenMusic series with OpenKara, by David Weng.