head to head · open source
Flagsmith vs Abby
Flagsmith has 6,559 GitHub stars, 568 forks, 711 open issues and last shipped yesterday. Abby has 166 stars, 30 forks, 31 open issues and last shipped 1.2 years ago. Flagsmith leads on adoption by 3,851% (6,559 vs 166 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 18%. 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 | ★ 166 |
| License | BSD-3-Clause | AGPL-3.0 |
| Written in | Python | TypeScript |
| Last push | 2026-09-17 | 2025-07-24 |
| Forks | ⑂ 568 | ⑂ 30 |
| 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
Flagsmith is an open source feature flag and remote configuration platform, written in Python and released under the BSD 3 Clause licence, for engineering teams that need to toggle, segment and roll out features across web, mobile and server side applications without deploying new code.
read the full Flagsmith overview →
About Abby
Abby is an open source, TypeScript feature management and A/B testing platform that pairs statically typed SDKs for core JavaScript, React, Next.js, Angular and Svelte with a dashboard the non developers on a team can use, aimed at developers who want feature flags and remote config without sending user data to a third party.
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Frequently asked questions
Is Flagsmith or Abby more popular?
Flagsmith has 6,559 GitHub stars and Abby has 166. 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 (6,559 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.