head to head · open source
fastapi vs Tailcall
fastapi has 102,471 GitHub stars, 9,913 forks, 78 open issues and last shipped 2 days ago. Tailcall has 7,637 stars, 1,467 forks, 45 open issues and last shipped yesterday. fastapi leads on adoption by 1,242% (102,471 vs 7,637 stars). fastapi is written in Python under MIT; Tailcall is written in Rust under Apache-2.0. fastapi has attracted 10% as many forks as stars, Tailcall 19%. Tailcall 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
| fastapi | Tailcall | |
|---|---|---|
| GitHub stars | ★ 102K | ★ 7.6K |
| License | MIT | Apache-2.0 |
| Written in | Python | Rust |
| Last push | 2026-09-18 | 2026-09-19 |
| Forks | ⑂ 9.9K | ⑂ 1.5K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick fastapi if
- You weight community size — 102K stars and counting
- You want the MIT license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick Tailcall if
- You want the Tailcall feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Rust
- You evaluated both and Tailcall fits your workflow better
About fastapi
FastAPI is an MIT licensed, high performance Python web framework for building APIs with standard Python type hints, aimed at Python developers and teams that need production ready HTTP services with automatic OpenAPI documentation.
read the full fastapi overview →
About Tailcall
Tailcall is an Apache 2.0 licensed, Rust based developer tool listed in this registry whose repository (tailcallhq/forgecode) and README present it as Forge, an AI enhanced terminal development environment: a command line coding agent that works against Claude, GPT, O Series, Grok, Deepseek, Gemini and, per its own description, more than 300 other models.
read the full Tailcall overview →
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Frequently asked questions
Is fastapi or Tailcall more popular?
fastapi has 102,471 GitHub stars and Tailcall has 7,637. fastapi has the larger community by that measure.
Are fastapi and Tailcall free?
Both are open source. fastapi is licensed under MIT and Tailcall under Apache-2.0. Neither carries a licence fee.
What is the difference between fastapi and Tailcall?
fastapi is written in Python and Tailcall in Rust. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, fastapi or Tailcall?
Choose fastapi if you want the larger community (102,471 stars) or its MIT licence terms. Choose Tailcall if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.