Open source — Apache 2.0 — v0.1.0Turn every database write into a real-time event.
kaptanto captures every insert, update, and delete from Postgres and MongoDB the moment it happens — and delivers it via stdout, SSE, or gRPC. One static binary. Self-contained. Deploys anywhere.
Sub-millisecond
Events flow from the WAL as each transaction commits. No polling interval, no artificial delay.
One event schema
The same JSON format across every source. Write your consumer once and connect to any database.
Crash-safe cursors
Per-consumer positions persist on every event. Reconnect and resume from exactly where you stopped.
Consistent backfills
Snapshot and stream run concurrently. Watermark coordination prevents stale or duplicate rows.
Per-key ordering
Events for the same primary key always arrive in commit order. Slow consumers never block other partitions.
Built-in HA
Two instances, one leader. Advisory lock election — session-scoped, no clock skew, ~5-second failover.
Database sources
Output modes
| Tool | Real-time | No Kafka | Multi-DB | Single binary | Free | Min cost |
|---|---|---|---|---|---|---|
| kaptanto | ✓ | ✓ | ✓ | ✓ | ✓ | $0 |
| Debezium | ✓ | ✗ | ✓ | ✗ | ✓ | $0+Kafka |
| Confluent | ✓ | ✗ | ✓ | ✗ | ~ | ~$200/mo |
| Fivetran | ✗ | ✓ | ✓ | ✗ | ~ | $12K/yr |
| Estuary | ✓ | ✓ | ✓ | ✗ | ✓ | $0 |
| AWS DMS | ✓ | ✓ | ✓ | ✗ | ✗ | ~$70/mo |
Your first event in two minutes.
Install kaptanto, point it at your database, and start streaming.