The official open-source Firely .NET SDK

FHIR API illustration
  • Open-source
  • Fully compliant with the standard
  • Speeds up implementation time
  • Lower the amount of coding


Get a running start in implementing FHIR the right way

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About .NET SDK

Drive health interoperability and save precious development time with Firely’s open-source FHIR Software Development Kit

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Implement .NET SDK

Use our expertise and best practices to smoothen your implementation project.

About Firely .NET SDK

Firely .NET SDK provides a set of tools and libraries that make it easier for developers to work with FHIR resources in .NET applications. It’s open source and can be downloaded from the GitHub repository. It is regularly updated to keep up with the latest developments in the FHIR standard.


A client library for interacting with FHIR servers using the FHIR RESTful API. Easily retrieve, create, update, and delete FHIR resources using standard HTTP methods.

FHIR Data Model

Easier to work with FHIR resources in .NET applications because of the classes and interfaces that represent the different types of FHIR resources.


Tools for serializing and deserializing FHIR resources in different formats, including JSON and XML


Validation of FHIR resources out of the box to ensure syntactical and semantical correctness.

Support for multiple FHIR versions

Work with any version of the FHIR standard, from the earliest releases to the latest and most cutting-edge versions, and ensure that your applications will continue to work seamlessly as the standard evolves over time.


Perform complex searches and manipulations on FHIR resources to retrieve specific data elements or transform them into new representations.


Working with FHIR profiles, including the ability to create profiles with the SnapshotGenerator. Define custom profiles, and use them to validate resources against custom constraints.

FHIR Packages

Manage FHIR resources, and organize them into logical groups and versions for easier management and sharing.

Unleash the power of your data

  • Serialization and deserialization to XML and JSON
  • Snapshot generation, validation, and caching
  • Set up complex resource resolving scenarios
  • Connect to other software and apps
// Find patients named Eve

var client = new FhirClient("");
Bundle results = await client.SearchAsync<Patient>(new string[] { "family:exact=Eve" });
// Just get the first patient

var patient = result.Entry[0].Resource as Patient;
// Add a name to the patient, and update

patient.Name.Add(new HumanName().WithGiven("Christopher").AndFamily("Brown"));
var updated_patient = client.Update(patient);

Take care of your implementation

Great products deserve great implementations. Firely provides all the training you need to better understand and implement FHIR.

FHIR Training Courses and Workshops for Health IT Professionals

Firely is of the initiators of the FHIR standard. Our training courses are aimed at implementers. Learn today, apply tomorrow.

FHIR training courses and workshops

Find out how Firely can help you bring FHIR to life

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