I built this to have a dedicated wire-protocol client for postgres logical replication.
General-purpose SQL clients either don't implement the replication protocol at all, or bury it behind abstractions designed for other use cases. Replication has a bit different mechanics - it's a stateful binary stream requiring LSN tracking, standby heartbeats, and feedback to prevent WAL bloat. Bolting that onto a query-focused client has its own challenges.<p>This is just the transport - raw XLogData frames and LSNs. Use pg_replicate, as an example, if you need "replicate to BigQuery." Use this if you're building replication infrastructure.<p>What it does:<p>- Explicit LSN control - start/stop at specific WAL positions for deterministic recovery<p>- Automatic standby feedback - no more forgotten heartbeats filling your disk with WAL<p>- Bounded channels - backpressure propagates to Postgres naturally<p>- Pure Rust, no libpq<p>What it doesn't do: pgoutput decoding (intentionally). That belongs in a higher layer.
Simplest way of using this:<p>while let Some(event) = client.recv().await? {
match event {
ReplicationEvent::XLogData { wal_end, data, .. } => {
process(&data);
client.update_applied_lsn(wal_end);
}
_ => {}
}
}
> Use pg_replicate, as an example, if you need "replicate to BigQuery." Use this if you're building replication infrastructure.<p>Would I use this if I host my own postgres and want to use replication for „real time backups“ into a hot standby?
I learned about this tonight when Claude Code picked up your library for my application that uses logical replication. Looking forward to putting it through its paces.
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