Open Source Licenses

Choose License by Goal

Goal	License
Maximum adoption, don’t care about attribution	MIT
Attribution + trademark/patent protection	Apache 2.0
Force derivatives to be open source	GPL-3.0
Force derivatives + SaaS to be open source	AGPL-3.0

License Feature Comparison

Aspect	MIT	BSD-3	Apache 2.0	GPL-3.0	AGPL-3.0
Use in proprietary software	Yes	Yes	Yes	No	No
Modify without sharing	Yes	Yes	Yes	No	No
SaaS use without sharing	Yes	Yes	Yes	Yes	No
Attribution required	Yes	Yes	Yes	Yes	Yes
Patent grant	No	No	Yes	Yes	Yes
Trademark protection	No	Yes	Yes	No	No

License Recommendations

MIT - Default for maximum adoption. Simple, short, universally understood.

BSD-3-Clause - Like MIT, adds “no endorsement” clause. Prevents using your name to promote derivatives.

Apache 2.0 - Attribution with protection. Includes patent grant (protects against patent trolls) and explicit trademark clause.

GPL-3.0 - Copyleft license. Derivatives MUST be open source. Does not cover SaaS.

AGPL-3.0 - GPL + closes the SaaS loophole. Network use triggers source disclosure. Effectively discourages corporate adoption.

Setting Up Apache 2.0 License

Download the license:

curl -s https://www.apache.org/licenses/LICENSE-2.0.txt -o LICENSE

Edit the LICENSE file:

1. Add Copyright <year> <name> at top
2. Remove APPENDIX section (ends at “END OF TERMS AND CONDITIONS”)
3. Clean up formatting (remove excessive indentation)

Update pyproject.toml:

license = "Apache-2.0"