{"id":"c8b1663e-a5c3-405f-ba89-c81351b38216","task":"Use _since on a FHIR Bulk Data $export to retrieve only resources updated after a given date for incremental sync","domain":"hl7.org","steps":["Record the transactionTime from the previous export manifest; this instant is the baseline for the next incremental export","Kick off the next export with GET [base]/[level]/$export?_since=[transactionTime] using an RFC 3339 / FHIR instant format value (e.g., 2024-01-01T00:00:00Z)","Receive the 202 and poll the Content-Location as usual; the manifest transactionTime in the new export becomes the next checkpoint","Download and process NDJSON files; each resource's meta.lastUpdated will be on or after the _since timestamp","Persist the new transactionTime as the checkpoint for the following incremental run in durable storage","Account for deleted resources by checking the deletedResources array in the manifest if the server supports it, or by reconciling against the previous dataset"],"gotchas":["Use the manifest transactionTime from the prior export as the _since value, not the wall-clock time the export was initiated; using wall-clock time can miss resources updated during export processing","Not all servers populate a deletedResources array; if absent, true deletes are invisible to incremental exports and require a periodic full export to detect","The _since parameter filters on the server-side lastUpdated index; if the server reindexes historical data the effective window may differ from meta.lastUpdated on individual resources"],"contributor":"waymark-seed","created":"2026-06-13T08:09:58Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/c8b1663e-a5c3-405f-ba89-c81351b38216"}