Introduction

FerroTERM is a pure-Rust FHIR terminology server. It serves SNOMED CT, LOINC, ICD-10, ICD-11, RxNorm, UCUM, and any FHIR CodeSystem through the HL7 FHIR terminology API from one binary, over an index built once per code system release and read at startup. There is no JVM, no Elasticsearch, and no database to run.

Note

The name: Ferro for the Rust family FerroTERM shares with FerroEHR, TERM for terminology. The site is https://ferroterm.eu.

Where the project is

v0.1.8 is the current release. It ships as Linux binaries for x86_64 and aarch64 (glibc and musl), as a container image for linux/amd64 and linux/arm64, and as a Compose file, all built with signed provenance. The server answers FHIR R4 under /r4, R4B under /r4b, R5 under /r5, and the R6 ballot under /r6; the CI lane runs the HL7 terminology ecosystem suite against the published versions on every change and holds a committed pass list per version.

Hierarchical expansion, persisted client resources, Bundle batch, $closure, and the SNOMED implicit concept maps are served. The persisted resources and the closure tables need a deployment that names a database in FERROTERM_RESOURCES, and $closure answers on /r4, /r4b, and /r5, since the R6 ballot defines no such operation. Where a mature terminology server does more, such as authoring SNOMED content and MRCM validation of post-coordinated expressions, this book says so. Each open item is an issue with acceptance criteria on the tracker, and the milestones are the roadmap.

Who each part of this book is for

• Evaluate is for anyone deciding whether FerroTERM fits: what it serves, why it exists, the architecture at a glance, and how it compares to Snowstorm, Ontoserver, and Hermes.
• Operate is for operators: installing and running the server, configuration, building an index from each code system’s release, hardware sizing, and verifying a release before you run it.
• Integrate is for API consumers: the FHIR terminology operations, the implicit value sets, the served FHIR version, and worked request and response examples captured from a running server.
• Contribute is for contributors: building and testing, the FHIR code generation model, and where the deeper design lives.

Two things that are always true

You bring your own code system content, and the software is source-available under the Business Source License 1.1: free to use outside production and in non-commercial production, a commercial licence for other production use, and Apache License 2.0 four years after each version. SNOMED CT is licensed by SNOMED International, LOINC by the Regenstrief Institute, ICD by the WHO, and RxNorm by the NLM; this repository and every build of FerroTERM ship none of their content. You load a release you are licensed for, and the server serves it. See Loading code systems.