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engineeringJune 7, 2026· 5 min read

Pure-Rust LSM storage engine: how it works and when to use it

Pure-Rust LSM storage engine, is a from-scratch WAL + MemTable + SSTable + bloom-filter + compaction engine in Rust, no RocksDB and no FFI. Here's how Crowkis does it and why it matters for cost and safety.

Every reworded repeat of a question you've already answered is a full-price model call. Pure-Rust LSM storage engine is how Crowkis is a from-scratch WAL + MemTable + SSTable + bloom-filter + compaction engine in Rust, no RocksDB and no FFI.

In plain words: In plain words: pure-rust lsm storage engine is a from-scratch WAL + MemTable + SSTable + bloom-filter + compaction engine in Rust, no RocksDB and no FFI.

How it works

Crowkis is a from-scratch WAL + MemTable + SSTable + bloom-filter + compaction engine in Rust, no RocksDB and no FFI. It runs inside one Redis-compatible engine, so it composes with semantic caching, agent memory, and the other intelligence layers instead of being a separate service you wire together.

Why it matters

Repetitive LLM workloads are where the money is, and semantic caching can cut costs up to 60-70% on repetitive workloads. Pure-Rust LSM storage engine is part of what makes that reuse safe rather than reckless, the difference between a cache you trust in production and one you audit after every incident. It's one self-hosted binary, Redis-compatible, free to run.

Infrastructure earns the critical path one boring, verifiable feature at a time.