orjson breaking changes
Every breaking API change we have recorded in orjson on PyPI: 4 breaking changes in 2 versions. Below are its newest 2 versions, removals and renames first, each with its source.
Newest change January 29, 2026
On this page
3.11.6
- Removed
The release ends support for Python 3.9. Users on Python 3.9 must upgrade Python or stay on an older orjson release. github.com
3.11.0
- Signature changed
orjson.dumps
Was def dumps(__obj: Any, default: Optional[Callable[[Any], Any]] = ..., option: Optional[int] = ...) -> bytes; now def dumps(__obj: Any, default: Callable[[Any], Any] | None = ..., option: int | None = ...) -> bytes. pypi.org - Signature changed
orjson.Fragment.contents
Was contents: Union[bytes, str]; now contents: bytes | str. pypi.org - Signature changed
orjson.loads
Was def loads(__obj: Union[bytes, bytearray, memoryview, str]) -> Any; now def loads(__obj: bytes | bytearray | memoryview | str) -> Any. pypi.org
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