head to head · open source
Flagsmith vs Cerbos
Flagsmith has 6,638 GitHub stars, 595 forks, 711 open issues and last shipped yesterday. Cerbos has 4,643 stars, 219 forks, 57 open issues and last shipped yesterday. Flagsmith leads on adoption by 43% (6,638 vs 4,643 stars). Flagsmith is written in Python under BSD-3-Clause; Cerbos is written in Go under Apache-2.0. Flagsmith has attracted 9% as many forks as stars, Cerbos 5%. Flagsmith was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Flagsmith | Cerbos | |
|---|---|---|
| GitHub stars | ★ 6.6K | ★ 4.6K |
| License | BSD-3-Clause | Apache-2.0 |
| Written in | Python | Go |
| Last push | 2026-11-02 | 2026-11-02 |
| Forks | ⑂ 595 | ⑂ 219 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Flagsmith if
- You weight community size — 6.6K stars and counting
- You want the BSD-3-Clause license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick Cerbos if
- You want the Cerbos feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Go
- You evaluated both and Cerbos fits your workflow better
About Flagsmith
Try our interactive demo Flagsmith is an Open Source Feature Flagging Tool to Ship Faster & Control Releases Change the way your team releases software. Roll out, segment, and optimise—with granular control. Stay secure with on premise and private cloud hosting. Feature flags: Release features behind the safety of a feature flag Make changes remotely: Easily toggle individual features on and off, and make changes without deploying new code A/B testing: Use segments to run A/B and multivariate tests on new features Segments: Release features to beta testers, collect feedback, and iterate Organisation management…
read the full Flagsmith overview →
About Cerbos
What is Cerbos? Cerbos is an authorization layer that evolves with your product. It enables you to define powerful, context aware access control rules for your application resources in simple, intuitive YAML policies; managed and deployed via your Git ops infrastructure. It provides highly available APIs to make simple requests to evaluate policies and make dynamic access decisions for your application. This repo has everything you need to set up a self hosted Cerbos Policy Decision Point (PDP). Sign up for a free Cerbos Hub account to streamline your policy authoring and distribution workflow to self hosted…
read the full Cerbos overview →
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Frequently asked questions
Is Flagsmith or Cerbos more popular?
Flagsmith has 6,638 GitHub stars and Cerbos has 4,643. Flagsmith has the larger community by that measure.
Are Flagsmith and Cerbos free?
Both are open source. Flagsmith is licensed under BSD-3-Clause and Cerbos under Apache-2.0. Neither carries a licence fee.
What is the difference between Flagsmith and Cerbos?
Flagsmith is written in Python and Cerbos in Go. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Flagsmith or Cerbos?
Choose Flagsmith if you want the larger community (6,638 stars) or its BSD-3-Clause licence terms. Choose Cerbos if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.