head to head · open source
fastapi vs spectral
fastapi has 104,566 GitHub stars, 10,179 forks, 78 open issues and last shipped yesterday. spectral has 3,247 stars, 305 forks, 222 open issues and last shipped 4 days ago. fastapi leads on adoption by 3,120% (104,566 vs 3,247 stars). fastapi is written in Python under MIT; spectral is written in TypeScript under Apache-2.0. fastapi has attracted 10% as many forks as stars, spectral 9%. fastapi was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 4 topic tags (json, json-schema, openapi, openapi3), 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 | spectral | |
|---|---|---|
| GitHub stars | ★ 105K | ★ 3.2K |
| License | MIT | Apache-2.0 |
| Written in | Python | TypeScript |
| Last push | 2026-11-02 | 2026-10-30 |
| Forks | ⑂ 10K | ⑂ 305 |
| 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 spectral if
- You want the spectral feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches TypeScript
- You evaluated both and spectral 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 spectral
[ ][stoplight forest] Custom Rulesets : Create custom rules to lint JSON or YAML objects Ready to use Rulesets : Validate and lint OpenAPI v2, v3.0, v3.1 & v3.2 , AsyncAPI , and Arazzo v1 Documents API Style Guides : Automated API Style Guides using rulesets improve consistency across all your APIs Ready to use Functions : Built in set of functions to help create custom rules. Functions include pattern checks, parameter checks, alphabetical ordering, a specified number of characters, provided keys are present in an object, etc. Custom Functions : Create custom functions for advanced use cases Overview 🧰…
read the full spectral overview →
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Frequently asked questions
Is fastapi or spectral more popular?
fastapi has 104,566 GitHub stars and spectral has 3,247. fastapi has the larger community by that measure.
Are fastapi and spectral free?
Both are open source. fastapi is licensed under MIT and spectral under Apache-2.0. Neither carries a licence fee.
What is the difference between fastapi and spectral?
fastapi is written in Python and spectral 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, fastapi or spectral?
Choose fastapi if you want the larger community (104,566 stars) or its MIT licence terms. Choose spectral if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.