pypi / aiobotocore
aiobotocore
What changed in aiobotocore 3, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-21.
1 deprecations3 new APIs and options7 fixes and other
See which of these apply to your code, ranked, in your agent:
npx @unstale/cli initaiobotocore 311 changes
Deprecations 1
The existing extra continues to work but installs the deprecated legacy httpx package and emits a DeprecationWarning when used.
New APIs and options 3
Streaming checksum bodies expose a new checksum property.
A new optional extra installs httpx2, Pydantic's maintained, API-compatible fork, for the httpx backend.
The optional httpx backend can run on trio as well as asyncio, making aiobotocore usable from trio-based projects.
Fixes and other changes 7
Calling close() on an already-closed session no longer raises AssertionError or masks the user's own exception.
The user-agent feature ID is registered when AioS3RegionRedirectorv2 follows a region redirect.
Checksum validation is skipped when no checksum is expected.
The max token is now seeded on the initial request attempt rather than appearing only after a retry.
Session management is now concurrency-safe.
Login credential refreshes call the generated asynchronous-compatible method directly instead of botocore's sync-only compatibility alias.
A per-request read_timeout override is now honored when computing retry timing.