head to head · open source
fastapi vs zato
fastapi has 104,566 GitHub stars, 10,179 forks, 78 open issues and last shipped yesterday. zato has 1,017 stars, 250 forks, 0 open issues and last shipped yesterday. fastapi leads on adoption by 10,182% (104,566 vs 1,017 stars). fastapi is written in Python under MIT; zato is written in Python under AGPL-3.0. fastapi has attracted 10% as many forks as stars, zato 25%. zato was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (api), 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
| fastapi | zato | |
|---|---|---|
| GitHub stars | ★ 105K | ★ 1.0K |
| License | MIT | AGPL-3.0 |
| Written in | Python | Python |
| Last push | 2026-11-02 | 2026-11-02 |
| Forks | ⑂ 10K | ⑂ 250 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick fastapi if
- You weight community size — 105K stars and counting
- You want the MIT license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick zato if
- You want the zato feature set and don't need the biggest community
- You prefer the AGPL-3.0 license terms
- Your stack matches Python
- You evaluated both and zato fits your workflow better
About fastapi
FastAPI framework, high performance, easy to learn, fast to code, ready for production Documentation : Source Code : FastAPI is a modern, fast (high performance), web framework for building APIs with Python based on standard Python type hints. The key features are: Fast : Very high performance, on par with NodeJS and Go (thanks to Starlette and Pydantic). One of the fastest Python frameworks available. Fast to code : Increase the speed to develop features by about 200% to 300%. Fewer bugs : Reduce about 40% of human (developer) induced errors. Intuitive : Great editor support. Completion everywhere. Less time…
read the full fastapi overview →
About zato
Zato /zɑːtəʊ/ ESB, SOA, API and Cloud Integrations in Python. Zato is a Python based, open source platform that lets you automate, integrate and orchestrate business systems, APIs, workflows as well as hardware assets in industries such as airports, defense, health care, telecommunications, financial services, government and more. What does it look like in practice? Learn more Visit for the details, including: Downloads Screenshots Programming examples
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Frequently asked questions
Is fastapi or zato more popular?
fastapi has 104,566 GitHub stars and zato has 1,017. fastapi has the larger community by that measure.
Are fastapi and zato free?
Both are open source. fastapi is licensed under MIT and zato under AGPL-3.0. Neither carries a licence fee.
What is the difference between fastapi and zato?
fastapi is written in Python and zato in Python. 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 zato?
Choose fastapi if you want the larger community (104,566 stars) or its MIT licence terms. Choose zato if its feature set, stack or AGPL-3.0 licence fits better. Both are self-hostable.