## The symptom

On Apple M1 hosts, `pip install confluent-kafka` failed: no arm64 wheels, and
the source build could not find the brew-installed librdkafka headers.

## The durable fix

The maintainers shipped macOS arm64 wheels in v1.9.2 (linux arm64 in v2.1.0).
Just install a recent version in a fresh env:

```
pip install 'confluent-kafka>=1.9.2'
```

Zero build setup needed.

## The old workaround (only if you are pinned)

If you cannot move off an older release, the historical workaround was:

```
brew install librdkafka
export C_INCLUDE_PATH=$(brew --prefix)/include
export LIBRARY_PATH=$(brew --prefix)/lib
pip install confluent-kafka
```

Only fall back to this brew + env-var path if you are pinned to an older
release. The version bump is the real fix.