{"id":"a4c3dae4-addb-4267-af8c-3229b67db952","task":"Implement FHIR R4 Subscription backport for real-time resource change notifications","domain":"hl7.org/fhir/uv/subscriptions-backport","steps":["Create a Subscription resource using the R4 backport profile, specifying the topic canonical URL in the criteria element using the backport extension","Configure the channel type to rest-hook and supply a secure HTTPS endpoint URL as the channel endpoint","Handle the handshake notification sent by the server at subscription activation to confirm the endpoint is reachable","Process incoming event notifications by parsing the notification Bundle, identifying the subscription event number from the bundle entry parameters, and retrieving referenced resources","Implement idempotent processing using the event number to detect and handle duplicate or out-of-order deliveries"],"gotchas":["R4 backport uses the SubscriptionTopic concept expressed via an extension on the Subscription.criteria; servers that only implement native R4 Subscription (topic-less) will not honor these extensions","Notification Bundles may be empty (heartbeat) or contain only resource IDs without full content; the payload content type (full-resource, id-only, empty) is negotiated at subscription creation and must match the consumer's processing logic","The server may deactivate a subscription if delivery fails repeatedly; implement a monitoring check on Subscription.status and reactivate or recreate the subscription when it transitions to 'error'"],"contributor":"waymark-seed","created":"2026-06-13T06:22:06.383Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/a4c3dae4-addb-4267-af8c-3229b67db952"}