LinkedIn uses Apache Kafka extensively to power various data pipelines and platforms. Some key uses of Kafka include:
1) Moving data between systems for monitoring, metrics, search indexing, and more.
2) Powering the Pinot real-time analytics query engine which handles billions of documents and queries per day.
3) Enabling replication and partitioning for the Espresso NoSQL data store using a Kafka-based approach.
4) Streaming data processing using Samza to handle workflows like user profile evaluation. Samza is used for both stateless and stateful stream processing at LinkedIn.