$ cat fastapi/week/2026-09-14.log
the week in review · Sep 14 – Sep 20, 2026
Pydantic adds counter and ordered-dict core schemas
By RepoJournal · composed from the cited sources · human-reviewed weekly · methodology
The two schemas follow earlier dict work so constraints apply properly, while CI hardening and enterprise vulnerability docs fill out the week.
Add a `counter` core schema pydantic/pydantic
The new schema continues the dict-schema line of work, and the PR notes it "allows constraints to apply properly" for counters. If you have hand-rolled counting types or post-validation checks for monotonic values, this is the shape that eventually replaces them.
Add an `ordered-dict` core schema pydantic/pydantic
An ordered-dict schema follows the same earlier dict work as the counter schema, so constraints behave consistently on mapping types whose key order matters. Relevant if you rely on insertion ordering and have been unable to express it as a constraint.
Fix documentation examples not raising and remove unused `string_sub_type` unused error code (#13821) pydantic/pydantic
Examples in the docs were not actually failing when they should have, and the fix came with removal of an unused string_sub_type error code. Docs that pass silently teach wrong behavior, so if you copied examples recently, re-run them against your pinned version.
Document coordinated vulnerability response in enterprise support (#13812) pydantic/pydantic
The new enterprise support page describes coordinated vulnerability response for covered release lines: named contacts, coordination, impact assessment, mitigations, patched releases, advisories, and CVE assignment. Private vulnerability reporting stays available to everyone, so the enterprise agreement adds process rather than exclusive access.
Add a debug Python test target in CI (#13820) pydantic/pydantic
A second CI job runs the suite against a debug build of Python, a follow-up to earlier work on the same target. Debug builds surface assertion and memory behavior that optimized builds hide, so regressions in those paths now have somewhere to be caught.
Fix PyEmscripten CI job (#13805) pydantic/pydantic
A second pass at the PyEmscripten job, after the first attempt landed earlier in the week. Still in progress, so treat WebAssembly CI results as settled only once this closes.
Fix PyEmscripten CI job pydantic/pydantic
The wire entry for the Emscripten fix, following the same trajectory as the developing item above. Nothing for your own code yet, just a signal that wasm-side testing is being actively repaired.
Document `url_preserve_empty_path` in network types (#13804) pydantic/pydantic
The url_preserve_empty_path option now has documentation in the network types, after previously existing without a described behavior. Worth reading if you parse URLs with empty paths and have guessed at what happens to them.
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