WalShadow is probably one of the most ambitious projects we’ve taken on. When we decided to build this six months ago, we genuinely weren’t sure how it would pan out. We were going directly after Postgres’s physical write-ahead log, an area backed by decades of deep engineering expertise. Now, seeing the early results with customers, especially Postgres → ClickHouse replication latency in the hundreds of milliseconds, it feels totally worth it. It opened up a new world tousers, that wasn’t possible before. This wouldn’t have been possible without the team’s deep expertise in Postgres replication, the operational lessons we’ve learned onboarding thousands of customers to Postgres CDC, and our experience deep in the Postgres replication and backups, creating and contributing to WAL-G and WAL-RUS I’m really excited for more customers to try it out. And perhaps the most exciting part: this brings ClickHouse much closer to becoming a physical analytics standby for Postgres. 🚀 github.com/ClickHouse/walsha… @ClickHouseDB