Type Hints at Run Time
Annotations cost nothing per call and everything at import. Reading __annotations__ takes 24 ns; resolving the same class with get_type_hints takes 3.4 µs, 140x more.
tooling
3 posts
Where Your Django Request Time Actually Goes
Removing Django's entire default middleware chain saved 0.02 ms per request. Fixing one N+1 query on the same view saved 3.30 ms.
What import Actually Does
Importing asyncio costs 21.9 ms and pulls in 100 modules. Importing email costs 0.1 ms and pulls in one. Granularity predicts import cost; size does not.