Who contributed to FastAPI & Pydantic on July 29, 2026?

3 developers shipped this update, including SAURABHSALVE, alex-raw, and YuriiMotov.

What were the notable FastAPI & Pydantic updates?

🐛 Fix `status_code` being ignored for SSE and JSONL streaming endpoints, 🐛 Fix stream item type lost when using `include_router()`, and 🐛 Fix handling sequences with nested Annotated types.

FastAPI & Pydantic

FastAPI and the Pydantic + SQLModel async-Python stack

Pick a date

Topics: Python Full archive →

The Wire · Showcase

FASTAPI FIXES STREAMING SCHEMA CHAOS ACROSS 4 CRITICAL BUGS

By RepoJournal · Filed 07:01 UTC on July 29, 2026 · About FastAPI & Pydantic

3 people shipped this

YuriiMotov @YuriiMotov 2 cited

SAURABHSALVE @SAURABHSALVE 1 cited

alex-raw @alex-raw 1 cited

FastAPI shipped fixes for four streaming and schema generation bugs that were silently breaking OpenAPI contracts and response validation across SSE, JSONL, and typed iterables.

The most urgent: SSE and JSONL streaming endpoints were ignoring declared `status_code` parameters and `Response` modifications, always returning 200 while OpenAPI documented whatever you declared [1]. That's a contract violation that will break client code expecting a different status. Equally critical, when those same streaming routes went through `include_router()`, the schema lost all stream item type information, turning `itemSchema` into an empty object [2]. Runtime behavior stayed correct, but any client relying on the OpenAPI spec to understand what they were receiving got nothing. Beyond streaming, two more bugs hit non-streaming routes: nested `Annotated` types in sequences were crashing at startup [3], and non-generator endpoints annotated with `Iterable[T]` were dropping all `response_model_*` serialization options like `exclude_unset` and `exclude_defaults` [4]. This period saw 17 commits and 6 releases across the repo, but these four fixes are what matter.

Action items

→ Upgrade FastAPI if you use SSE or JSONL streaming endpoints - status codes are now honored fastapi/fastapi [immediate]
→ Regenerate OpenAPI specs for routed streaming endpoints to pick up corrected item schemas fastapi/fastapi [plan]
→ If using nested Annotated types with Query() or Body(), upgrade to unblock startup fastapi/fastapi [immediate]
→ Audit any Iterable[T] endpoints using response_model_exclude_* for missing serialization fastapi/fastapi [plan]

References

[1] 🐛 Fix `status_code` being ignored for SSE and JSONL streaming endpoints ↗ fastapi/fastapi
[2] 🐛 Fix stream item type lost when using `include_router()` ↗ fastapi/fastapi
[3] 🐛 Fix handling sequences with nested Annotated types ↗ fastapi/fastapi
[4] 🐛 Fix `response_model_*` params ignored for non-generator endpoints with `Iterable[..]` return type ↗ fastapi/fastapi

Quick answers

What shipped in FastAPI & Pydantic on July 29, 2026?: FastAPI shipped fixes for four streaming and schema generation bugs that were silently breaking OpenAPI contracts and response validation across SSE, JSONL, and typed iterables. In total, 17 commits, 20 pull requests, and 6 releases landed.
Who contributed to FastAPI & Pydantic on July 29, 2026?: 3 developers shipped this update, including SAURABHSALVE, alex-raw, and YuriiMotov.
What were the notable FastAPI & Pydantic updates?: 🐛 Fix `status_code` being ignored for SSE and JSONL streaming endpoints, 🐛 Fix stream item type lost when using `include_router()`, and 🐛 Fix handling sequences with nested Annotated types.

FASTAPI DITCHES DEPENDENCY FLATTENING, CUTS OPENAPI GENERATION BLOAT

FastAPI is ripping out the dependency tree flattening that bloated OpenAPI schema generation, replacing it with direct graph traversal that preserves order and skips duplicates without the synthetic overhead.

python 52 shipped 1-min read

FastAPI & Pydantic 4 days ago

FASTAPI 0.140.0 CUTS MEMORY OVERHEAD IN DEPENDENCIES

FastAPI shipped a memory optimization that simplifies how dependencies are processed, backed by months of community analysis and benchmarking.

python 9 shipped 1-min read

FastAPI & Pydantic 5 days ago

FASTAPI AND SQLMODEL STANDARDIZE ON UV, PYDANTIC DOCS BLOCKED ON SETTINGS DRIFT

Tiangolo shipped Library Skills documentation across FastAPI and SQLModel while pivoting both projects toward uv as the default package manager, but Pydantic's docs build is failing due to version mismatch in pydantic-settings.

python 10 shipped 1-min read

FastAPI & Pydantic 6 days ago

SQLMODEL FIXES TERMYNAL SCROLL JAR ACROSS DOCS

Interactive code examples in SQLModel documentation no longer hijack your scroll position when you click the restart or fast-forward controls.

python 2 shipped 1-min read

Elsewhere on the wire

AI Agents about 3 hours ago

LANGCHAIN CORES SHIP, ANTHROPIC THINKING BLOCKS FIXED, OPENHANDS TIGHTENS WEBSOCKET AUTH

LangChain released two core packages with critical fixes for streaming stability and environment variable handling, while OpenHands closed a security gap that left WebSocket connections unprotected.

ai-agents 119 shipped 1-min read

Local LLMs about 4 hours ago

OLLAMA RIPS OUT IMAGE GENERATION, LLAMA.CPP SHIPS SPECULATIVE DECODING

Ollama removed its entire MLX image generation pipeline overnight, while llama.cpp landed DSpark speculative decoding and fixed a critical SYCL memory bug affecting Arc GPUs.

+11

llms 239 shipped 2-min read

@CachyOS about 4 hours ago

KERNEL SCHEDULER UPDATES ACROSS BORE AND SCX TOOLING

CachyOS shipped BORE 6.8.0 patches across two kernel series while upgrading its sched-ext ecosystem in parallel, signaling major tuning work ahead.

infra 83 shipped 1-min read

Elixir & Phoenix about 4 hours ago

ELIXIR TIGHTENS ERROR HANDLING ACROSS DATE, ECTO, AND IEXHELPERS

Date.range now surfaces ArgumentError instead of Protocol.UndefinedError when passed invalid step values, catching a class of bugs that silently fail in production code.