The HL7 Da Vinci Project produces the FHIR Implementation Guides that CMS-0057-F relies on. The ecosystem covers Coverage Requirements Discovery, Documentation Templates and Rules, Prior Authorization Support, Payer Data Exchange, Health Record Exchange, and a growing set of value-based care and risk-adjustment IGs. For US health payers preparing for January 1, 2027, understanding the Da Vinci ecosystem is not optional. The IGs change over time, the conformance patterns evolve, and the Connectathon results inform real vendor capability. This guide lays out what the ecosystem actually looks like in 2026 for the Da Vinci ecosystem hub on this site.
What Da Vinci Actually Is
Da Vinci is an HL7 FHIR Accelerator focused on payer-provider data exchange. The project includes major US payers, EHR vendors, integration vendors, and standards organizations. It produces FHIR Implementation Guides that solve specific clinical and administrative use cases at the payer-provider boundary.
Da Vinci is not CMS, but CMS-0057-F references Da Vinci IGs as the conformance baseline for several of its requirements. The Prior Authorization API requirement, the ePA stack (CRD / DTR / PAS), and parts of Patient Access and Payer-to-Payer Data Exchange all anchor on Da Vinci-produced IGs.
The IGs That Matter Most for CMS-0057-F
The CMS-0057-F-relevant Da Vinci IGs cluster into three groups. The ePA stack: CRD, DTR, PAS. The data exchange layer: PDex, PDex Plan Net, HRex. The supporting IGs: CARIN BB (technically CARIN Alliance, not Da Vinci, but closely related), US Drug Formulary.
For a deeper breakdown of which IGs matter and how they relate, the Top 6 Da Vinci IGs every health plan should track in 2026 covers the priority list.
How Connectathons Inform Real Capability
HL7 Connectathon events are where vendors test their Da Vinci implementations against each other. The Connectathon results expose what actually works in practice, not just what passes Inferno tests. Real-world integration scenarios surface compatibility gaps between vendor implementations of the same IG.
For payers evaluating vendor claims, Connectathon results are a more honest signal than vendor marketing. Vendors that show up to Connectathons, document their results publicly, and demonstrate integration with multiple counterparts have stronger evidence of production capability than vendors who skip them.
For specific Connectathon results worth examining during vendor selection, the Top 5 Connectathon results that inform Da Vinci vendor selection covers what to look for.
The Conformance Layer Underneath All Da Vinci IGs
Inferno is the conformance suite of record for CMS-0057-F. Inferno tests each Da Vinci IG independently and the combined stack. The Inferno tests pass when an implementation meets the spec; the tests do not test all production behaviors.
Production-grade Da Vinci implementations pass Inferno (necessary) and also handle the production behaviors Inferno does not test (sufficient). The gap between conformance and production is real; the gap explains why some Inferno-passing vendors still have implementation issues in the field.
For the Inferno conformance patterns that matter most in production, the Top 5 Inferno conformance patterns for Da Vinci implementations covers the testing layer.
How the IGs Evolve Across Versions
Da Vinci IGs ship in versions (STU 1.0, STU 2.0.0, STU 2.0.1, etc.). The version-to-version differences matter for production deployment. A platform built against an older version may pass conformance for that version while being non-conformant for the current version CMS-0057-F references.
The IG maintenance question (whose responsibility is it to keep up with Da Vinci version updates) is one of the load-bearing questions during vendor selection. Vendors that own this maintenance handle the work as IGs evolve. Vendors that disclaim it leave the maintenance to the payer engineering team.
How to Engage With Da Vinci as a Health Plan
Most US health plans participate in Da Vinci passively (using the IGs that Da Vinci produces) rather than actively (contributing to IG development). Active participation has benefits: early visibility into IG changes, influence over IG direction, and connection to the broader payer-provider integration community. Larger payers (the major BCBS plans, large Medicare Advantage carriers) tend to participate actively. Smaller payers usually participate passively, with their vendors handling the active engagement on their behalf.