fhir is a work in progress, tracking todo items at https://github.com/PotatoEMR/gleam-fhir/issues, if anything is incorrect, missing, hard to use, or poorly documented, please add an issue.

0.6.0 May 6, 2026

• split other fhir versions into separate packages, so fhir only provides r4
• split fhir clients using http clients into separate packages, so fhir only provides resources and sansio
• fhir_client_httpc uses httpc
• fhir_client_rsvp uses rsvp
• switch example package with primitive extensions on all fields from r4 with us core types to plain r4
• add enum of resource types, and use it to make any_delete public taking resource type rather than actual resource instance

0.5.0 April 18, 2026

• Add batch request that takes list of Request(Option(Json))
  • In order to create batch all requests go from String to Option(Json)
• Fix 0.4.0 bug where search/operation expect res_type but server returns different resource
• Add sansio get next paginated bundle, and httpc get all paginated bundles at once

0.4.0 April 12, 2026

• Change response parsing to check for resource of given type (eg AllergyIntolerance) or OperationOutcome rather than go off of http status
• Change delete operation response parsing
• • If no response body, can still return Ok response if http status code < 300
• • If response body has OperationOutcome, return it in Ok or Error depending on http status code < 300
• Separate sansio errors for creating request and parsing response

0.3.0 April 11, 2026

• Fix incorrect to_json for 1..1 choice type
• Parse date, dateTime, instant, and time into custom type, instead of String
• When parsing resource of potentially type, on failure, include resource type (eg Immunization) in DecodeError path

0.2.0 Mar 15, 2026

• Remove r4 and r4b to fit in hex.pm size limit (probably due to recent change https://github.com/hexpm/hex_core/commit/4383e1b08aaf7d6dd325154d02f91e37f55b16b4, modules need to be reorganized at some point for package size and compilation/LSP speed)
• Add custom types for complex extensions
• Add primitive extensions
• Add r4us with us core extensions
• Generate r4usp, but not publish due to size limit

0.1.0 Feb 07, 2026

• Change integer64 from Int to String in Gleam, as integer64 is sent as string in JSON, and is relatively uncommon, R5 only
• Remove unused SpInclude with _include and _revinclude from resource search params
• Add search_any in clients, which takes a flexible (includes, modifiers, prefixes, etc.) but not necessarily correct String rather than statically typed search params
• Add operation_any in clients, which similarly lets user choose operation name and parameters

0.0.0 Feb 01, 2026

• Gleam types for FHIR data types and resources
• JSON encoder and to_json functions
• Enums for valuesets with required binding
• Sans-io request/response for Create, Read, Update, Delete, Search
• Search parameter types for each resource, but basic params only
• Client layers over sans-io for httpc and rsvp
• Supports R4, R4B, R5
• Parses many valid FHIR JSON examples, but does not guarantee json -> encode -> to_json roundtrip will output same json as original, in particular there is a loss of implicit precision in decimal types, contrary to FHIR spec. At some point the decimal type will change, which will be a breaking change
• Uses String for Date and DateTime, which will at some point change to a real time type in a breaking change
• No primitive extensions support, so primitive elements will change in some undecided way
• This is an initial release with various problems, so there could be breaking changes in any module