Skip to content

sct

A fast, local-first SNOMED CT toolkit written in Rust. Convert a SNOMED CT RF2 release into queryable formats in seconds. Almost ridiculously fast on modern hardware. Free and open source. No Java. No Elasticsearch. Docker optional.

cargo install sct-rs

sct ndjson  --rf2 ~/path-to-your-SNOMED-RF2.zip/

sct sqlite  --ndjson snomed.ndjson

sct lexical "heart attack"

Full walkthrough · Get your own terminology server · Why build this? · Benchmarks

  • Build the pipeline

    Convert an RF2 snapshot into SQLite, Parquet, Markdown, or Arrow embeddings in a single command. 837,930 concepts in under a minute on a laptop.

    Walkthrough

  • Search

    Full-text search via FTS5 for keywords and phrases. Typo-tolerant fuzzy and prefix search via a mmap'd FST index. Semantic vector search via local Ollama embeddings. All offline.

    sct lexical · sct fst · sct semantic

  • Code lists & ECL

    Build version-controllable clinical code lists, and populate them with SNOMED CT Expression Constraint Language - sct codelist add --ecl "<<73211009" expands a query into concrete concepts.

    sct codelist

  • Connect to AI

    A local MCP server exposes SNOMED CT as tools for Claude, Cursor, and any other MCP-compatible client. Ask questions about concepts, hierarchies, and relationships directly in your AI assistant.

    sct mcp

  • Run a terminology server

    Start a FHIR R4 SNOMED CT terminology server on a clean VPS with Docker Compose. First boot downloads from TRUD, builds snomed.db, and serves $lookup, $expand, $subsumes, and $translate.

    Get your own server · sct serve

  • Explore

    A keyboard-driven terminal UI and a local web GUI for browsing concepts, navigating hierarchies, and inspecting relationships - no browser extension or remote service needed.

    sct tui · sct gui