Apache 2.0 Practical Guide | Generated by AI
Question: What does the Apache License 2.0 mean in practice?
Answer: Standard permissive OSS license. Key mechanics:
You can:
- Use, modify, distribute, sublicense — commercially or privately, no restrictions on your own code that merely links to it.
- Keep your own license on your modifications (dual-licensing your changes is fine).
You must:
- Include a copy of the license with any distribution.
- Mark changed files as modified (a comment header noting you changed it is enough).
- Preserve existing copyright/attribution notices from the original source.
- If a
NOTICEfile exists in the original, carry its contents forward in your distribution (file, docs, or UI credits — your choice where).
Patent grant (the part that differs from MIT): Each contributor grants you a patent license covering their contributions. But if you sue anyone claiming the Work infringes your patent, your patent license from this project terminates immediately. This is the defensive clause — protects the project from patent trolls emerging from within the contributor base.
No warranty, no liability — standard AS-IS, no support obligation on the licensor.
What it does NOT require:
- No requirement to open-source your own derivative work (unlike GPL) — you can build closed-source products on top of Apache-2.0 code.
- No “copyleft” — you don’t have to release your changes to the public, just mark that you changed the files if you redistribute them.
For your stack (ww/iclaw/zz, model training scripts): if you pull in an Apache-2.0 dependency and ship a binary/CLI, you just need to bundle the LICENSE file and preserve NOTICE if one exists. No obligation to open your own agent code.
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