The healthcare integration engine, and the part you can do for free
An integration engine does four jobs: transport, transformation, routing and reliability. The fiddly one — turning HL7 v2 into FHIR R4 — you can do right here, in your browser, with no engine to deploy.
A healthcare integration engine is the middleware that moves clinical messages between systems — receiving HL7 v2 over MLLP, transforming it (often to FHIR), routing it, and acknowledging it. Mirth Connect, Rhapsody, Cloverleaf and Intersystems are the well-known engines. If the specific job you need is the transformation step — HL7 v2 → FHIR R4 — this free in-browser converter does exactly that, with no engine to stand up.
What an integration engine actually does
| Job | What it means | This free tool |
|---|---|---|
| Transport | Receive/send over MLLP, TCP, files, REST | No — engine territory |
| Transformation | HL7 v2 → FHIR R4, mapping & normalization | Yes — free, in-browser |
| Routing | Filter & fan messages to destinations | No |
| Reliability | ACKs, queues, retries, monitoring, audit | No |
So an engine is four jobs; the hard, fiddly one for most teams is transformation. That’s the part you can do here for free.
Open-source & open integration engines
Teams looking for an open integration engine usually do so after Mirth Connect moved to a commercial, NextGen-licensed model. Open options exist, but standing one up is heavy if all you need today is to see — or script — what an HL7 message looks like as FHIR. For that, skip the engine:
When you still need a full engine
If you need to receive live HL7 feeds over MLLP, route them, acknowledge them and monitor delivery, that’s a real integration engine’s job — this tool doesn’t replace it. What it replaces is the transformer you’d otherwise hand-write inside one. We build conversion and data infrastructure for healthcare; the converter is the free, open piece of it.
Zkeleton builds conversion and data infrastructure for healthcare. This converter is free, runs entirely in your browser, and never sends a message anywhere — we keep it open because clean data plumbing should be a commodity, not a toll.