Chapter 11 - Multi-tenant HAPI - Cold open

Last chapter we sketched the interceptor. Now we wire it for production.

One HAPI server, many clinics. Multi-tenancy is the feature that turns a single FHIR server into a platform - and the one place where a single bug silently shows Clinic A another clinic's patients. So we treat isolation as the thing we must never get wrong.

Three goals for this chapter

Choose a HAPI partitioning mode that isolates clinics Wire a tenant registry - clinic slug to partition id Recognise two cross-tenant footguns before they leak

One rule that bites hardest here

Pin your tag - HAPI 8.x partitioning semantics moved across minors