$ the-wire · showcase
Pydantic deletes the V1 escape hatch
By RepoJournal · Filed · About FastAPI & Pydantic · Composed from the cited sources · methodology
Pydantic is clearing out every deprecated surface at once: the pydantic.v1 namespace, V1 backwards compatibility, deprecations accumulated across the 2.x line, and two create_model and dataclass parameters, all in a single sweep that arrives in the next major.
Remove `pydantic.v1` namespace (#14156) pydantic/pydantic
The pydantic.v1 namespace is gone, so import pydantic.v1 as pydantic_v1 no longer resolves anywhere in your tree. Any service still routing int/str-style V1 models into V2 code through that shim has to be ported to native V2 models before the next major.
Remove V1 backwards compatibility and functionality deprecated since 2.0 (#14139) pydantic/pydantic
V1 backwards compatibility and everything deprecated since 2.0 is removed outright, which means code that has been emitting DeprecationWarnings through the 2.x cycle has now run out of runway. Treat the warning list from your existing test run as the migration checklist.
Remove functionality deprecated during the 2.x timeline (#14158) pydantic/pydantic
Functionality deprecated partway through the 2.x timeline goes as well, so a deprecation announced in a mid-2.x minor is only now billed. This is the same change spread across a wider surface: less obvious in a grep, more likely to surface as a runtime error than a warning.
Remove the `__validators__` argument of `create_model()` and the `validate_on_init` dataclass parameter (#14163) pydantic/pydantic
The __validators__ argument of create_model() and the validate_on_init parameter on dataclasses are both gone. Dynamic model factories that inject validators through that keyword, and dataclasses relying on init-time validation, need restructuring rather than a rename.
📝 Update release notes fastapi/fastapi
The FastAPI side was routine: a release-notes commit from the latest-changes bot and a sponsor addition for MicroAuth, with no framework behavior in either.
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