Who contributed to FastAPI & Pydantic on June 9, 2026?

2 developers shipped this update, including Viicos and dependabot[bot].

What were the notable FastAPI & Pydantic updates?

Handle missing errors with default factories taking validated data and ⬆ Bump sqlalchemy from 2.0.49 to 2.0.50.

FastAPI & Pydantic

FastAPI and the Pydantic + SQLModel async-Python stack

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PYDANTIC CLOSES GAP ON DEFAULT FACTORY VALIDATION, SQLMODEL INHERITS SQLALCHEMY FIX

By RepoJournal · Filed 06:04 UTC on June 9, 2026 · About FastAPI & Pydantic

2 people shipped this

Viicos @Viicos 1 cited

dependabot[bot] @dependabot[bot] 1 cited

Pydantic now properly validates data passed to default factories, closing a gap that forced developers to work around missing field initialization.

Pydantic fixed a validation gap where default factories weren't receiving validated data when fields were missing [1]. This surfaces a real problem: you'd write a factory expecting clean input, but get raw, unvalidated data instead, forcing downstream validation logic that shouldn't exist. The fix applies across all factory patterns and should eliminate a class of runtime bugs in production systems that rely on defaults. In related infrastructure news, SQLModel bumped SQLAlchemy to 2.0.50 [2], which fixes a joinedload issue when combined with of_type() on joined-table subclasses. This is the kind of ORM edge case that only hits you in production, so the bump is critical for anyone using those patterns. Both updates ship without breaking changes.

Action items

→ Upgrade pydantic to latest patch to fix default factory validation pydantic/pydantic [plan]
→ Update SQLAlchemy in sqlmodel projects to 2.0.50 if using joinedload with of_type tiangolo/sqlmodel [plan]

References

[1] Handle missing errors with default factories taking validated data ↗ pydantic/pydantic
[2] ⬆ Bump sqlalchemy from 2.0.49 to 2.0.50 ↗ tiangolo/sqlmodel

Quick answers

What shipped in FastAPI & Pydantic on June 9, 2026?: Pydantic now properly validates data passed to default factories, closing a gap that forced developers to work around missing field initialization. In total, 1 commits and 2 pull requests landed.
Who contributed to FastAPI & Pydantic on June 9, 2026?: 2 developers shipped this update, including Viicos and dependabot[bot].
What were the notable FastAPI & Pydantic updates?: Handle missing errors with default factories taking validated data and ⬆ Bump sqlalchemy from 2.0.49 to 2.0.50.

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