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Apache Flink
Apache Flink is a distributed engine for stateful stream processing and batch analytics with event-time semantics, fault tolerance, and scalable deployment on clusters.
Apache Flink is a distributed processing engine for stateful stream processing and batch analytics. It is designed for low-latency, high-throughput pipelines with strong consistency, fault tolerance, and event-time processing.
Key Features
- Stateful stream processing with exactly-once consistency (depending on connector and sink support)
- Event-time semantics with watermarks and advanced windowing
- Fault tolerance via checkpoints and savepoints for upgrades, rollbacks, and migrations
- Unified runtime for streaming and batch workloads
- Rich APIs including DataStream and Table/SQL for declarative processing
- Scalable parallel execution on clusters with fine-grained state management
Use Cases
- Real-time analytics and monitoring pipelines over logs and events
- Stream ETL and enrichment between messaging systems and databases
- Stateful event-driven applications such as fraud detection or alerting
Limitations and Considerations
- Operating Flink reliably requires careful tuning of state backends, checkpoints, and connector configuration
- Some delivery guarantees depend on the chosen connectors and sinks, not only the core engine
Apache Flink is well-suited for teams building reliable, stateful real-time systems and unified streaming/batch data pipelines. It provides robust primitives for event-time processing and recovery, while scaling from small deployments to large cluster environments.