Who contributed to FastAPI & Pydantic on August 25, 2026?

1 developer shipped this update, including Victorien.

What were the notable FastAPI & Pydantic updates?

Do not drop include/exclude if serializer wasn't called (#13702), Support `populate_by_name` in `@validate_call`, and Add additional tests for forward references resolving.

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PYDANTIC FIXES SERIALIZER EXCLUSION BUG

By RepoJournal · Filed 06:59 UTC on August 25, 2026 · About FastAPI & Pydantic

1 person shipped this

Victorien @Viicos 4 cited

Pydantic's most requested validation fix just landed, and it's exactly what your custom serializers have been waiting for.

Pydantic shipped a critical fix [1] that stops include/exclude filters from being silently dropped when a custom serializer isn't invoked, resolving issue #13601 and making output filtering predictable again. The same author also pushed support for `populate_by_name` in `@validate_call` [2], closing issue #13687 and bringing decorator behavior in line with model config. Forward references get extra test coverage [3] to lock down resolution edge cases from issue #13681, and a new docs publish CI [4] should keep the documentation pipeline green. With 7 commits and 7 PRs across the repo, this is a focused day of hardening. Test the serializer fix against your field-exclusion logic before your next release.

Action items

→ Test your custom serializer include/exclude flows against the fix in PR 13702 before next deploy pydantic/pydantic [immediate]
→ Review #validate_call usage for populate_by_name support pydantic/pydantic [plan]
→ Watch the forward references test additions for edge-case regressions pydantic/pydantic [monitor]

References

[1] Do not drop include/exclude if serializer wasn't called (#13702) pydantic/pydantic
[2] Support `populate_by_name` in `@validate_call` ↗ pydantic/pydantic
[3] Add additional tests for forward references resolving ↗ pydantic/pydantic
[4] Add new docs publish CI (#13700) pydantic/pydantic

Quick answers

What shipped in FastAPI & Pydantic on August 25, 2026?: Pydantic's most requested validation fix just landed, and it's exactly what your custom serializers have been waiting for. In total, 7 commits and 7 pull requests landed.
Who contributed to FastAPI & Pydantic on August 25, 2026?: 1 developer shipped this update, including Victorien.
What were the notable FastAPI & Pydantic updates?: Do not drop include/exclude if serializer wasn't called (#13702), Support `populate_by_name` in `@validate_call`, and Add additional tests for forward references resolving.

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