Installing confluent-kafka from source failed with fatal error: 'librdkafka/rdkafka.h' file not found because the build needs the librdkafka C library headers first. Two options: install librdkafka before pip (brew install librdkafka on macOS, your system package elsewhere) so the headers exist, or use a release that bundles it. Since v0.11.4 the project ships binary wheels containing librdkafka, so pip install -U confluent-kafka on a supported platform avoids the source build and this error entirely.