DOC · license SPDX · MIT EFFECTIVE · 2026.01.01
LEGAL / MIT LICENSE

MIT License — use it, fork it, ship it.

Callahan CI is distributed under the MIT license. It's one of the shortest and most permissive licenses in open source. The full text is reproduced below, followed by a plain-English summary.

SPDX ID
MIT
COPYRIGHT
2026 — present
HOLDERS
Callahan CI Contributors

The license text

LICENSE · MIT55 lines · canonical
MIT LicenseCopyright (c) 2026 Callahan CI Contributors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

In plain English

The MIT license is permissive. In practice, it means:

  • ✔
    Use it for anything. Personal, commercial, internal, embedded in a closed-source product — all fine.
  • ✔
    Modify it. Fork, edit, extend. You don't have to share your changes.
  • ✔
    Distribute it. Ship it as part of your product, open or closed source.
  • ✔
    Sell it. Build a business on top of it. No royalties.
  • !
    Keep the copyright notice. Include the MIT license text in any copy or substantial portion you distribute.
  • ×
    No warranty. Provided as-is. If Callahan melts your CI, that's on you.

Third-party dependencies

Callahan bundles or dynamically links a handful of open-source libraries. Each is licensed under a compatible permissive license (MIT, Apache-2.0, BSD-3, or ISC). The complete list with versions lives in /THIRD_PARTY_NOTICES.md in the repo.

Contributors

This project is the work of the Callahan CI Contributors. If you have sent a pull request that has been merged, you are one of them. Thank you.