Sustainable Use License (Fair Code)

The Sustainable Use License (often associated with the "Fair Code" movement) is a "Source Available" license, not a strictly Open Source license (OSI definition). It grants you broad rights to view, modify, and use the software for free—with one critical restriction.

🛡️ RISK BADGE: 🔴 RESTRICTIVE (Source Available)

Executive Summary: What is it?

The Sustainable Use License (often associated with the "Fair Code" movement) is a "Source Available" license, not a strictly Open Source license (OSI definition). It grants you broad rights to view, modify, and use the software for free—with one critical restriction.

The Restriction: The "Anti-Amazon" Clause

You cannot use the software to build a competing product where the software is the service.

CFO / Business Impact: What does it cost/risk?

Safe for Internal Use. For 99% of enterprise use cases (using the software to run your business), it functions exactly like Open Source. You pay nothing. The risk only exists if your business model involves re-selling the software itself as a cloud service.

Technical Reality: How does it work?

The code is open on GitHub. You can fork it, fix bugs, and deploy it via Docker. The only technical difference is often a mandatory telemetry ping or specific features locked behind a commercial key (Enterprise Edition), depending on the specific vendor's implementation.

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