Fig. 1

High-level architecture of Ontoserver. Ontoserver is a RESTful server that provides three APIs: a FHIR API, implemented using the HAPI FHIR library, to support terminology functionality, an administration API used to implement functionality that is not defined in the FHIR specification, such as uploading a SNOMED CT code system in RF2 format, and a syndication API that is used to consume and expose syndicated terminology resources. It uses a Postgres database to store FHIR resources and a Lucene index to support searching. The application is deployed using Docker