Maxwell's Daemon

What Maxwell's Daemon is

Maxwell's Daemon is a free, open-source tool for capturing changes from MySQL databases and sending them as JSON to streaming platforms. It reads MySQL binary logs, using a log-based capture method, and documents output producers for Kafka, Kinesis, SQS, SNS, NATS, Google Cloud Pub/Sub, BigQuery, RabbitMQ and Redis. Listed uses include ETL, database change auditing, cache building or expiring, search indexing and communication between services. It supports schema evolution and an initial snapshot.

Filtering can select events by database, table or column values. JavaScript filters allow custom row filtering and data changes. When encryption is enabled, Maxwell encrypts messages with AES/CBC/PKCS5PADDING using a key supplied by the user, then base64-encodes the values. Metrics can be exposed through logging, JMX, HTTP or Datadog; HTTP endpoints cover metrics, Prometheus, health checks, ping and diagnostics. The software runs on Linux in a self-hosted deployment. The quick start describes command-line and Docker use and provides a binary distribution and a Homebrew installation command. Documented requirements include JRE 11 or above and MySQL 5.1, 5.5, 5.6, 5.7 or 8; Kafka 0.8.2 or greater is required when using Kafka. With MySQL's MINIMAL row image setting, UPDATE and DELETE output may be incomplete, and INSERT output leaves out column default values.

Who it suits

Maxwell's Daemon suits technical teams that need to stream MySQL changes into Kafka or other documented destinations for ETL, auditing, indexing, cache work or service communication. It fits Linux environments where teams can manage a self-hosted deployment and its runtime and database requirements.

Limits

The software is free, with no usage limits stated on the opened pages. With binlog_row_image=MINIMAL, UPDATE and DELETE output may be incomplete, and INSERT output omits column default values. The documented client-side high-availability approach is experimental and alpha quality, and requires at least three Maxwell nodes for leader elections.

Getting started

1. Review the documented JRE and MySQL requirements, and the Kafka requirement if using Kafka.
2. Choose a documented output producer such as Kafka, Kinesis, SQS, SNS, NATS, Google Cloud Pub/Sub, BigQuery, RabbitMQ or Redis.
3. Use the quick start to run Maxwell from the command line or Docker.
4. Alternatively, use the provided binary distribution or Homebrew installation command.
5. Find source code and bug tracking through GitHub.

Verdict

Choose Maxwell's Daemon if you need a free, self-hosted way to stream MySQL changes as JSON and can operate its Linux deployment. Check the MINIMAL row image caveat if your database uses that setting, and treat its documented high-availability approach as experimental.