FastAPI 0.140.0 is out with a focus on performance, documentation improvements, and internal tooling. The release cleans up dependencies and modernizes the docs.
Key Changes
- 🔧 Reduced memory usage in dependencies (PR #16049 by @tiangolo). The internal dependency graph now uses a more efficient representation, lowering overhead for apps with many dependencies.
- 📝 Updated documentation defaults – all docs now recommend
uvprojects as the standard setup (PR #16032). This aligns with current Python packaging best practices. - 📚 Added Library Skills documentation (PR #16041), a new section to help developers integrate FastAPI with external libraries.
- 🔗 Fixed broken links in multiple doc pages (PR #15967 by @YuriiMotov).
- 🏗️ Restructured FastAPI People pages (PR #16015), splitting sponsors, contributors, and teams into clearer sections.
- ⚙️ Added CI memory benchmark (PR #16046). The CI now runs
memory_profilerduring tests to track memory regressions. - 🧹 Removed obsolete scripts for generating FastAPI People data (PR #16016).
Why This Matters
For developers, the dependency memory reduction (especially in high-concurrency apps) means lower per-request overhead. The uv-first docs simplify setup, while the Library Skills page makes it easier to find integration guidance. CI memory benchmarks help prevent subtle leaks in future releases.
Source: https://github.com/fastapi/fastapi/releases/tag/0.140.0