Open-Source Licences
The open-source software inside Cusp, where to find the full licence notices, and how to get source code for LGPL components.
Last updated
Cusp is proprietary software made by Wex Labs Limited, and it's built on a great deal of open-source software. We're grateful to everyone who maintains it. Each component stays under its own licence, and nothing in our Terms of Service restricts the rights those licences give you.
Where to find the full notices
Every Cusp release includes the complete list of third-party components, with their versions, licences and full licence texts:
| Product | Where |
|---|---|
| Desktop app | App menu → Open-Source Licenses |
| iOS app | Settings → Acknowledgements |
| CLI and daemon | THIRD_PARTY_NOTICES file in each release archive |
| VS Code extension | THIRD_PARTY_NOTICES file inside the extension package |
| Website and web app | This page, and the notices published with each release on GitHub |
What's inside, in short
- Mostly permissive licences: MIT, Apache-2.0, BSD, ISC and similar cover the large majority of components.
- Fonts: Inter, Geist Mono and Source Serif 4 are used under the SIL Open Font License 1.1.
- Mozilla Public License 2.0: a few Rust libraries in the desktop app (for example
nucleo-matcher,cssparserandselectors). We use them unmodified. Their source code is available from crates.io. - GNU Lesser General Public License: the Cusp daemon and CLI are built with Bun, which statically links the JavaScriptCore engine (LGPL-2.0 or later) and TinyCC (LGPL-2.1). On Linux, the desktop AppImage also contains WebKitGTK and GTK (LGPL-2.1 or later) as unmodified shared libraries.
Source code for LGPL components
The source code of the LGPL components we distribute is available from their projects: JavaScriptCore as modified for Bun at github.com/oven-sh/WebKit, TinyCC at repo.or.cz/tinycc.git, and WebKitGTK and GTK at webkitgtk.org and gtk.org.
You have the right to modify these libraries and to relink Cusp with your modified versions. For at least three years after we distribute a release, we'll provide, on request and for no more than the cost of providing it, the materials you need to do that for the daemon and CLI: the compiled application code in a form that can be relinked with a modified Bun runtime, and the Bun version used. Where a release includes them, they're published as cusp-relink-<platform>.tar.gz on its downloads page, with instructions inside. For any release, including one without them, or if you can't download them, email legal@cusp.run with the release version and your platform.
Questions
If you think we've missed a notice or got one wrong, email legal@cusp.run and we'll fix it.