FastAPI 0.143.0

I upgraded my API stack to FastAPI 0.143.0 this morning, and the verdict is quick: pull before you push. This one shipped October 8, 2026, and it carries one breaking change you want to read first.

The Big Change: OpenTelemetry Opt-In

Automatic OpenTelemetry exporter setup is now opt-in. If you relied on FastAPI to configure exporters automatically, you will need to enable it explicitly after upgrading. FastAPI Cloud sets this up for you automatically, but self-hosted apps must opt in.

Why It Matters

• Stops unexpected exporter configuration in apps that never asked for it
• Gives you full control over where traces go
• Small, focused breaking change: one config switch

Upgrade Notes

Bump your dependency, flip the exporter flag, run the test suite. Then you are on 0.143.0 with no surprises. Worth updating.