Maxwell's Daemon
Maxwell's Daemon reads the MySQL binary log and writes row-level changes as JSON to Kafka, Kinesis, and other streaming platforms — a single-purpose CDC process with no framework around it.
LicenseOpen source (permissive)· Apache-2.0
DeploymentSelf-hosted
PricingFree
Operational complexityLow
WorkloadStreaming
LanguageJava
Use it when
- The need is exactly this: MySQL changes as JSON on Kafka or Kinesis, consumable without a schema registry or deserializer.
- Operational weight must stay minimal; one JVM process replaces a connector framework, and setup is measured in minutes.
- Classic CDC consumers are the audience: ETL feeds, audit logs, cache invalidation, search-index maintenance.
- Budget is zero; Apache-2.0 with no commercial edition.
Think twice when
- Any source besides MySQL exists or is planned; there is no PostgreSQL, SQL Server, Oracle, or MongoDB path, and there will not be (Debezium covers those).
- Delivery guarantees must be stronger than at-least-once with careful producer settings (acks=all, retries).
- Schema-aware payloads matter; events are plain JSON rows, with DDL tracked in Maxwell's own schema store rather than in a registry.
How it runs
A single Java process tails the binlog (binlog_format=row, replication grants, and its own maxwell schema on the source) and writes JSON events to Kafka, Kinesis, and other targets. maxwell-bootstrap loads existing tables; include/exclude filters and JavaScript hooks shape the stream.
Details
CompareHow Maxwell's Daemon answers the questions Change Data Capture turns on.
Change Data Capture
| How it works | |
| Initial snapshot | maxwell-bootstrap for initial table load |
| End-to-end lag | Near real-time; tails the binlog continuously |
| Delivery guarantee | At-least-once: requires acks=all and retries |
| Schema drift | Tracks DDL in its own schema store; can emit DDL events |
| Running it | |
| What you run | One JVM process; state kept in a maxwell schema on MySQL |
| Connections | |
| Sources | MySQL only |
| Source requirements | binlog_format=row, REPLICATION grants, and its own maxwell schema |
| Transformations | Include/exclude filters; JavaScript hooks can edit or suppress rows |
| Destinations | Kafka, Kinesis and other stream targets |
| Cost | |
| Billing unit | None: Apache-2.0 with no commercial edition |
Alternatives to Maxwell's Daemon
