Versioning and deprecation

How the FHIR R4 and REST v1 interfaces, webhook payloads and SDKs change, and how breaking changes are announced.

• FHIR R4 at /fhir/R4 and REST v1 at /v1 are stable interfaces. Additive changes (new fields, new resource types, new endpoints, new event types) ship without notice; the SDKs and docs/openapi.json are regenerated in the same commit and a test fails otherwise.
• Breaking changes get a new prefix (/v2) and at least 6 months of parallel operation; the old prefix answers with a Deprecation and Sunset header during that period.
• Webhook payloads carry a type; new types are additive. A subscriber to * must ignore unknown types.
• SDKs follow semver; a major SDK version may drop a sunset API prefix.
• Security fixes may tighten validation (for example value sets) without a version bump; such tightening is announced in the changelog with 30 days' notice unless it closes an active vulnerability.

Conformance enforcement (announced 23 September 2026)

Writes that miss IPS / HL7 Europe laboratory requirements currently return 201/200 with an Anpheros-Conformance header. After an observation period (planned: 60–90 days from this notice) the platform switches to block mode: such writes answer 422 with an OperationOutcome listing every gap. Integrators that need more time can be exempted per project during the transition. Resource types added 23 September 2026: Procedure, DiagnosticReport, CarePlan, FamilyMemberHistory, ServiceRequest, Goal (additive).