FastAPI 0.143.4 has been published as a maintenance release. The headline change is narrow but practical: the project now lists httpx2 among its optional dependencies. The release notes frame this as a dependency upgrade rather than a feature drop, so there are no new public APIs or behavioural changes to plan around. The work landed via pull request #16512, authored by @tiangolo, the project's maintainer.
The concrete changes in this release:
- Added httpx2 to FastAPI's optional dependencies, so environments that opt into the extra dependency set pick it up automatically (PR #16512 by @tiangolo).
- Classified the work under the release's "Upgrades" section, indicating dependency hygiene rather than new functionality.
- No breaking changes, deprecations, or new endpoints are announced in the release notes.
For most teams this is a low-risk bump. Optional dependencies in FastAPI are what support tooling and integrations that aren't required for the core framework, and test clients are a common consumer. If you install FastAPI with the optional extras, your resolver may now pull httpx2 where it previously did not, which is worth checking if you pin dependencies tightly or build lockfiles for CI. Projects that install only the base package are unaffected.
Because this release carries no API surface changes, upgrade planning should be straightforward: bump the version, confirm your lockfile resolves cleanly, and run your test suite to verify nothing in your HTTP client setup shifts. Teams maintaining custom dependency pins may want to add httpx2 explicitly to avoid resolver surprises, while those relying on FastAPI extras can let the metadata handle it. The release is a good reminder to review optional extras periodically, since they quietly define what gets installed alongside the framework.
Source: https://github.com/fastapi/fastapi/releases/tag/0.143.4