Walrus is a lock-free, single-node Write Ahead Log in Rust that rips through a million ops/sec and moves 1 GB/s of write bandwidth - on bare-metal, nothing fancy. It leans on mmap-backed sparse files, atomic counters, and zero-copy reads to get there.
Each topic gets its own line of 10MB memory-mapped blocks, stuffed inside 1GB files. Cleanupβs handled with checkpoint-driven deletion. No coordination overhead - just a lean async job runner and CPU-pinned writers keeping things moving.
