FHIR at WillInteroperability on your terms try it

Your systems don’t
speak FHIR—yet.

FHIR at Will is the bridge.

An open-source, AI-powered interoperability layer that turns your existing clinical data into FHIR R4 resources—while your infrastructure evolves.

>_ try the playground view on github
</> open source ⎈ self-hostable ↯ byok / byom ☷ implementation-guide aware

Your systems

  • ◫ HIS / EMR
  • ▣ LIS
  • ▦ RIS / PACS
  • ◇ Pharmacy
  • ☰ Billing
… and more
FHIR
at Will AI Translation
+ Verification
Cascade

FHIR ecosystem

  • ◫ EHRs
  • ↯ HIEs / HINs
  • ♣ Patient Apps
  • ⏲ Analytics
  • ◯ Research
… and more

› A bridge, not a replacement

Use FHIR at Will to become interoperable now.

Continue running your existing systems.

Adopt native FHIR when you’re ready.

Built on a simple truth

☑

Conformant isn’t necessarily correct.

FHIR validity doesn’t catch clinically impossible data.

◉

Trust requires verification.

Every resource is checked across 8 layers before it’s trusted.

⇆

Uncertain goes to review.

We fail closed when something can’t be verified.

› Verification-first by design

FHIR at Will implements an 8-layer validation cascade so you can trust what you interoperate.

Try it live → Learn more →
L1StructuralIs it valid FHIR R4?
L2ProfileDoes it conform to required profiles?
L3TerminologyAre codes valid and in their ValueSets?
L4InvariantsDo FHIRPath invariants hold?
L5PlausibilityIs the value clinically possible?
L6FidelityIs each element supported by source data?
L7CoverageWhat clinical information was omitted?
L8RoutingAuto-accept, review, or reject?

› How it works

From legacy data to FHIR.

One verification-first pipeline between the data you have and the ecosystem you need.

01
↯

Connect

Connect your existing healthcare data sources without replacing the systems that run your facility.

02
◎

Translate

FHIR at Will uses AI to understand and map clinical data into FHIR R4 resources.

Roadmap
03
◇

Verify

Validate structure, profiles, terminology, invariants, plausibility, and routing decisions.

Available today
04
⌘

Interoperate

Expose standardized FHIR resources to the systems, applications, and platforms that need them.

› Built for the real world

No clean-room assumptions.

✦

FHIR R4

Standards-based resources and FHIR-native operations.

◎

AI-ready translation

Provider-neutral architecture for future narrative extraction.

▥

IG aware

Validate against preloaded implementation guides.

⌘

Terminology

ValueSet validation and ConceptMap translation.

↯

Clinical plausibility

Catch impossible values schemas cannot see.

ƒ

FHIRPath invariants

Run applicable business and consistency rules.

◇

Provenance

Version information makes verdicts reproducible.

▣

Self-hostable

Keep control of deployment and data boundaries.

⌂

Open source

Inspect, extend, and build on the foundation.

↗

BYOK / BYOM

Bring-your-own-provider architecture is on the roadmap.

› Foundation first

A roadmap with the foundation first.

The platform is centered on the validation foundation today. Narrative ingestion, AI provider routing, extraction, fidelity and coverage scoring, and review workflows follow on top of it.

See the detailed roadmap →
  1. M0
    Platform foundationConfig, storage, auth, health, containers
    Complete
  2. M1
    Validation cascadeProfiles, terminology, invariants, plausibility
    Complete
  3. M2
    Provider gatewayBYOK / BYOM routing and qualification probes
    Planned
  4. M3
    Narrative to FHIRExtraction, fidelity, and coverage
    Planned
  5. M4+
    Human review & deliveryCalibrated routing and integrations
    Planned

[ developers welcome ]

Built in the open.
Better with you.

Help shape practical, trustworthy healthcare interoperability. Contribute code, improve the docs, report issues, or bring a new idea.

View on GitHub → Join the community

[ open source · self-hostable ]

Healthcare interoperability should be open.

Inspect it. Run it. Extend it. Build on it.

$ git clone https://github.com/fhir-at-will/fhir-at-will.git
$ cd fhir-at-will
$ docker compose up -d
Star on GitHub