6 comments

  • sacs0ni 5 days ago

    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.

    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.

    What it does:

    - Explicit LSN control - start/stop at specific WAL positions for deterministic recovery

    - Automatic standby feedback - no more forgotten heartbeats filling your disk with WAL

    - Bounded channels - backpressure propagates to Postgres naturally

    - Pure Rust, no libpq

    What it doesn't do: pgoutput decoding (intentionally). That belongs in a higher layer. Simplest way of using this:

    while let Some(event) = client.recv().await? { match event { ReplicationEvent::XLogData { wal_end, data, .. } => { process(&data); client.update_applied_lsn(wal_end); } _ => {} } }

    • nkmnz an hour ago

      > Use pg_replicate, as an example, if you need "replicate to BigQuery." Use this if you're building replication infrastructure.

      Would I use this if I host my own postgres and want to use replication for „real time backups“ into a hot standby?

      • radimm an hour ago

        Not OP - but definitely no. In such a case use just physical or - if you have special use case - logical replication that’s built in.

        • sacs0ni 36 minutes ago

          I agree. pgwire-replication is useful when you need to build a customized and closely controlled pipeline. In fact, it will give you the first part of handling the data (reading from the source), you still need to implement the rest yourself.

    • malodyets 2 days ago

      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.

      • sacs0ni 2 days ago

        nice! would appreciate any feedback.