Most payers do not author Da Vinci IGs directly. They consume the IGs HL7 publishes and customize at the profile or extension level when needed. A few larger payers contribute to IG development through HL7 working groups. Either path requires the right tooling. Five tools dominate FHIR profile development in 2026, each with different strengths. For Da Vinci implementation patterns coverage on this site, these are the practical tools.
What FHIR Profile Development Actually Involves
A FHIR profile is a constraint on a base FHIR resource. The base Patient resource is permissive about which fields are populated; a US Core Patient profile constrains it (identifier must include MRN, name must be present, gender must be coded). Da Vinci IGs include their own profile sets on top of base FHIR (CRD profiles, DTR Questionnaire profiles, PAS Bundle profiles).
Authoring a profile involves writing the constraints in FHIR's profile description language (StructureDefinition resources), validating that the constraints are coherent, and producing the publishable IG output (HTML documentation, machine-readable artifacts).
1. SUSHI With FSH (FHIR Shorthand)
SUSHI is the HL7-maintained tool for authoring FHIR profiles using FHIR Shorthand (FSH), a domain-specific language for FHIR profile definitions. Authors write profiles in FSH (which is much more concise than raw StructureDefinition JSON), and SUSHI compiles to the standard FHIR profile artifacts.
This is the default tool for HL7-published Da Vinci IGs. The HL7 build system uses SUSHI; authors contributing to Da Vinci work directly with FSH. For payers extending Da Vinci profiles for internal use, learning FSH is the path of least resistance.
2. Forge by Firely
Forge is a commercial visual profile editor from Firely. Authors edit profiles in a UI rather than writing FSH or raw JSON. The tool is well-suited to teams that include clinical or domain experts who are uncomfortable with text-based tooling.
Forge can export to standard FHIR profile artifacts, making the output compatible with the broader FHIR ecosystem. For organizations with substantial profile authoring needs and a mix of technical and clinical authors, Forge is the established commercial option.
3. Trifolia-on-FHIR
Trifolia-on-FHIR is an open-source web-based profile editor. Authors edit profiles in a browser without installing software locally. The tool fits collaborative authoring scenarios where multiple authors edit the same IG.
Adoption is moderate; the open-source nature makes it attractive for teams without budget for commercial tools.
4. Simplifier.net by Firely
Simplifier.net is a cloud-based platform from Firely for FHIR resource management, profile development, and IG publishing. It integrates with Forge and supports the full IG authoring workflow from profile editing through publication.
For organizations that author multiple IGs (large vendor or consultancy), Simplifier provides the publication and version-management infrastructure that ad-hoc tooling does not.
5. Inferno Profile Validator
Inferno is primarily a conformance testing suite, but the embedded validation tools also work for profile development. Authors can validate test resources against profiles during development, catching constraint violations before the IG is published.
The pattern is to develop the profile in SUSHI or Forge, then validate sample resources against it using Inferno's tooling before finalizing the IG.
What "IG Conformance Maintenance" Actually Requires Tool-Wise
For payers consuming Da Vinci IGs rather than authoring them, the tool requirements are lighter. The platform that ships the IG-conformant FHIR endpoints handles most of the work. The payer team may need lightweight validation tooling to verify that internal data feeds produce IG-conformant resources after the platform's profile validation.
For payers extending IGs (adding custom extensions, custom profiles for internal use), the full authoring toolchain matters. SUSHI plus a visual editor (Forge or Simplifier) covers most cases.
How Tool Choice Affects Vendor Negotiations
A useful pattern during vendor negotiations is to ask which tools the vendor uses for IG conformance work. Vendors using HL7-standard tooling (SUSHI, FSH) integrate more cleanly with the broader Da Vinci community. Vendors using proprietary tooling produce profiles that may be harder to validate independently.
For the broader Da Vinci IG landscape that these tools work on, the Top 6 Da Vinci IGs every health plan should track in 2026 covers the IGs themselves. For the Inferno conformance patterns that validate authored profiles in production, the Top 5 Inferno conformance patterns for Da Vinci implementations covers the testing layer.