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Intermediate

keygen

A fair source software licensing and distribution API built with Ruby on Rails.

Updated Jun 13, 2025

By Zeke Gabrielse

Free Open Source Standalone App Real World Example

Price: Free

Description

Keygen is a fair source software licensing and distribution API, built for developers, by developers. Use Keygen to add license key validation, entitlements, and device activation to your business's desktop apps, server applications, on-premise software, and other products.

Software licensing for everyone

Keygen comes in two editions. Keygen CE is our Community Edition, and is free (as in beer) to self-host for personal and commercial use. Keygen EE is our Enterprise Edition, and it requires a license key to use. Keygen EE comes with dedicated support, as well as enterprise-grade features like request logs, audit logs, permissions, environments, and more.

We built Keygen to make software licensing accessible to everyone.

This is a great reference project to learn how Zeke built and managed all this stuff. There is actually a fantastic IndieRails podcast episode where he talks all about his experience. Highly recommend checking that out if you're at all interested.

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