Kafka Connect is a scalable, fault-tolerant framework for streaming data between Kafka and external systems without writing custom consumer or producer code. Source connectors pull data from external systems — databases, file systems, REST APIs — and publish it to Kafka topics. Sink connectors consume messages from Kafka topics and write them to external systems — databases, data warehouses, S3, Elasticsearch. The Connect framework handles parallelism, fault tolerance, offset tracking, and schema management automatically, reducing a complex integration task to a configuration exercise.
Kafka Connect is the correct architectural choice whenever the integration task is moving data between Kafka and a well-supported external system without custom transformation logic. Writing a custom Kafka producer to read from a PostgreSQL table and write to Kafka is reinventing the Debezium or JDBC Source Connector — which already handles incremental loading, CDC via WAL replication, schema registration, and fault-tolerant offset tracking. Custom producers should be reserved for sources with no available connector, novel authentication requirements, or transformations that the Single Message Transform framework cannot express.