Egres

Egres is an open-source, Postgres-compatible database designed for heavy, multi-tenant workloads. Built from first principles using Zig and the libpg_query library, it speaks the Postgres protocol so existing tools, drivers, and ORMs connect without code changes. It uses a custom storage engine called zdb alongside a fiber-based query execution system. Built for developers managing demanding database environments, Egres handles thousands of tenants on a single process. It features per-query and per-tenant metering for CPU ticks, memory, and disk IOPS, and supports running on local disk or object storage like S3 with Raft-based replication.