Learn Open Health Stack

The three architectural pillars​

Open Health Stack is a collection of open-source tools and libraries organized into three complementary pillars. Each pillar provides standards-based building blocks designed to work together or independently.

Pillar 1 for FHIR Foundations​

Unbundled Kotlin Multiplatform core libraries, on-device storage, and UI rendering toolkits that integrate into any digital health application.

• Core FHIR libraries provide type-safe models (fhir-model) across Android, iOS, desktop, and web for FHIR R4, R4B, and R5, with an architecture ready for future releases including FHIR R6, alongside Kotlin FHIRPath (fhir-path) for clinical logic. Explore Kotlin FHIR and Kotlin FHIRPath.
• Kotlin Multiplatform FHIR SDK provides on-device SQLite storage, search, sync, and Structured Data Capture (SDC) forms. Explore Kotlin FHIR Engine and Kotlin FHIR Data Capture.
• Android FHIR SDK provides native Android libraries for offline storage, sync, and form rendering.
• Back-end services include Info Gateway and FHIR Data Pipes for reverse proxy authentication and batch SQL-on-FHIR pipelines.
• Platform support and version compatibility details supported Kotlin Multiplatform targets and tested versions. Explore Platform support and Version compatibility.

Explore complete FHIR Foundations documentation →

Pillar 2 for OHS Player reference toolkit​

An end-to-end reference toolkit showing how foundational building blocks assemble into a working digital health application stack.

• What OHS Player is explains the philosophy of reference composition and modular assembly. Explore the OHS Player overview.
• The architecture and building blocks illustrates how clients, web portals, gateway security, FHIR servers, and analytical pipelines connect, and how the toolkit consumes foundational libraries. Explore The architecture.
• The components details the individual reference components. Explore the Components directory.
• The configuration model explains how standard FHIR resources drive screen layouts and workflows without custom code. Explore the Configuration model.
• What you can do today outlines current reference capabilities and maturity. Explore Current capabilities.

Explore complete OHS Player reference toolkit →

Pillar 3 for AI Commons (Incubating)​

An active incubation track focused on artificial intelligence safety and structured healthcare standards.

• FHIR prompt tooling helps developers query, translate, and extract structured FHIR data with language models.
• Benchmarking suites test model accuracy, clinical protocol compliance, and hallucination rates against clinical datasets.
• Privacy frameworks support on-premise execution and automated clinical data de-identification.

What Open Health Stack leaves to the broader ecosystem​

Open Health Stack integrates directly with established tools across the FHIR and Global Goods community rather than rebuilding them.

• FHIR authoring tools like Aidbox Form Builder, LHC-Forms, FHIR Shorthand, and Trifolia-on-FHIR create forms, questionnaires, and implementation guides.
• FHIR data transformation engines like OpenFn, Apache Camel, and Mirth Connect handle complex enterprise data mapping and scheduled aggregate transfers.
• FHIR servers and repositories like HAPI FHIR, Medplum, Aidbox, IBM FHIR Server, and commercial cloud repositories store and index health resources natively.

Where to go next​

• If you want to understand strategic benefits and total cost of ownership, read the executive briefing in About Open Health Stack.
• If you want to evaluate adoption models and national system coexistence, explore Adoption pathways.
• If you want hands-on deployment scripts, codelabs, or configuration recipes, dive into Build and quickstart.