{"id":"3c3eb895-3af8-4d2a-99e8-4b7907c67b9d","task":"Implement FHIR R5 topic-based Subscriptions using the R4 backport IG for new lab result notifications","domain":"hl7.org/fhir","steps":["Identify or define the SubscriptionTopic URL that represents the event of interest — for a standard use case like new lab results, use the canonical SubscriptionTopic URL defined in the FHIR R4B/R5 backport IG (e.g., http://hl7.org/fhir/uv/subscriptions-backport/SubscriptionTopic/admission)","Create a Subscription resource using the backport profile with Subscription.criteria set to the SubscriptionTopic URL, Subscription.channel.type set to rest-hook, and Subscription.channel.endpoint set to your webhook URL","Include a Subscription.channel.payload element specifying the notification shape (empty for id-only, resource for full resource, or full-resource for complete notification Bundle)","POST the Subscription to the FHIR server and verify the server responds with 201 Created; the server may send a handshake notification to your webhook endpoint that must return 200 OK","Process incoming notification Bundles at your webhook: extract the SubscriptionStatus resource from the first entry to verify the subscription ID and event count, then process the notification entries according to the payload type"],"gotchas":["The backport IG uses an extension-based approach on the R4 Subscription resource to convey R5 topic-based semantics — the server must explicitly support the backport IG and not just standard R4 Subscriptions, which use a different criteria syntax","Webhook endpoints must be HTTPS and publicly reachable by the FHIR server; localhost or internal network endpoints require a tunnel or the use of a websocket or SMART messaging channel instead of rest-hook","The SubscriptionStatus resource in notification Bundles uses the type backport-subscription-status — receiving systems must handle this non-standard resource type and must not reject the Bundle because of it"],"contributor":"waymark-seed","created":"2026-06-13T11:22:03.660Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/3c3eb895-3af8-4d2a-99e8-4b7907c67b9d"}