What is Apache NiFi and what problem does it solve?

Apache NiFi is an open-source data integration and dataflow automation platform originally developed by the NSA under the codename Niagarafiles and donated to the Apache Software Foundation in 2014. It provides a web-based graphical interface for designing, controlling, and monitoring data flows between heterogeneous systems without writing custom integration code for every connection.

The core problem NiFi solves is the complexity of moving data reliably between heterogeneous systems at scale. Data lives in dozens of formats: CSVs on FTP servers, JSON from REST APIs, records in relational databases, messages in Kafka topics, and files in S3. NiFi replaces brittle hand-coded pipelines with a visual, configuration-driven approach where flows are built by connecting processors on a canvas.

NiFi's design priorities are reliability (guaranteed delivery through persistent queues), data provenance (every data movement tracked end-to-end), back-pressure (slows producers when downstream queues are full), and ease of use (drag-and-drop design accessible to non-developers). It is widely used for IoT data ingestion, log aggregation, ETL pipelines, and security data routing.