How to build fast similarity search for email from the ground up · Blog · Sublime Security

### Executive summary: This engineering deep-dive describes how Sublime groups similar email messages by converting message fields into tokenized and shingled sets, generating fixed-size MinHash fingerprints, and using banding to rapidly retrieve high-similarity candidates at scale; it also analyzes error tradeoffs when tuning band and row parameters and provides a Postgres-based inverted-index implementation for live clustering and low-latency similarity lookup.