Sorted:

Apache Storm Serialization Guide

Apache Beam Execution Engines: Complete Guide

Apache Beam vs. Other Stream Processing: Which Wins?

Apache Beam Timestamps & Watermarks Guide

Apache Beam Windowing Guide

Kafka Deployment Options Guide

ZooKeeper Client-Server Communication Explained

Hive Components: Metastore, Driver, Executor Roles

ZooKeeper in HBase: Key Roles Explained

ZooKeeper Session Expiration Guide