head to head · open source
Flagsmith vs Abby
Flagsmith has 6,638 GitHub stars, 595 forks, 711 open issues and last shipped yesterday. Abby has 167 stars, 49 forks, 31 open issues and last shipped 1.3 years ago. Flagsmith leads on adoption by 3,875% (6,638 vs 167 stars). Flagsmith is written in Python under BSD-3-Clause; Abby is written in TypeScript under AGPL-3.0. Flagsmith has attracted 9% as many forks as stars, Abby 29%. Flagsmith was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 3 topic tags (feature-flags, feature-toggles, hacktoberfest), so they are genuine substitutes rather than adjacent tools.
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 | Abby | |
|---|---|---|
| GitHub stars | ★ 6.6K | ★ 167 |
| License | BSD-3-Clause | AGPL-3.0 |
| Written in | Python | TypeScript |
| Last push | 2026-11-02 | 2025-07-24 |
| Forks | ⑂ 595 | ⑂ 49 |
| 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 Abby if
- You want the Abby feature set and don't need the biggest community
- You prefer the AGPL-3.0 license terms
- Your stack matches TypeScript
- You evaluated both and Abby 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 Abby
About Abby Abby is a open source feature management and A/B testing platform. It is designed to be easy to use and easy to integrate into your existing applications. It aims to improve the developer experience by providing a simple and statically typed API for feature management and A/B testing. Besides its official SDKS it also offers a friendly and easy to understand Dashboard for the non developers in your team. Abby focuses on privacy. This means it won't track any personalized user data and uses no marketing cookies. You can self host it or use the hosted version available at tryabby.com. Getting Started…
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Frequently asked questions
Is Flagsmith or Abby more popular?
Flagsmith has 6,638 GitHub stars and Abby has 167. Flagsmith has the larger community by that measure.
Are Flagsmith and Abby free?
Both are open source. Flagsmith is licensed under BSD-3-Clause and Abby under AGPL-3.0. Neither carries a licence fee.
What is the difference between Flagsmith and Abby?
Flagsmith is written in Python and Abby in TypeScript. 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 Abby?
Choose Flagsmith if you want the larger community (6,638 stars) or its BSD-3-Clause licence terms. Choose Abby if its feature set, stack or AGPL-3.0 licence fits better. Both are self-hostable.