Hl7.Fhir.Specification.STU3 4.3.0

The ID prefix of this package has been reserved for one of the owners of this package by NuGet.org. Prefix Reserved
.NET 6.0 .NET Standard 2.0 .NET Framework 4.5.2
dotnet add package Hl7.Fhir.Specification.STU3 --version 4.3.0
NuGet\Install-Package Hl7.Fhir.Specification.STU3 -Version 4.3.0
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="Hl7.Fhir.Specification.STU3" Version="4.3.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add Hl7.Fhir.Specification.STU3 --version 4.3.0
#r "nuget: Hl7.Fhir.Specification.STU3, 4.3.0"
#r directive can be used in F# Interactive, C# scripting and .NET Interactive. Copy this into the interactive tool or source code of the script to reference the package.
// Install Hl7.Fhir.Specification.STU3 as a Cake Addin
#addin nuget:?package=Hl7.Fhir.Specification.STU3&version=4.3.0

// Install Hl7.Fhir.Specification.STU3 as a Cake Tool
#tool nuget:?package=Hl7.Fhir.Specification.STU3&version=4.3.0
STU3 R4 R4B R5
Build Status Build Status Build Status Build Status
Nuget Nuget Nuget Nuget


This is the official support SDK for working with HL7 FHIR on the Microsoft .NET (dotnet) platform.

Release notes

Read the releases notes on firely-net-sdk/releases. You can find documentation about this SDK in the Firely docs site.

What's in the box?

This library provides:

  • Class models for working with the FHIR data model using POCO's
  • Xml and Json parsers and serializers
  • A REST client for working with FHIR-compliant servers
  • Helper classes to work with the specification metadata, most notably StructureDefinition and generation of differentials
  • Validation of instances based on profiles
  • Evaluation FhirPath expressions

IMPORTANT Before installing one of the NuGet packages (or clone the repo) it is important to understand that HL7 has published several updates of the FHIR specification, each with breaking changes - so you need to ensure you use the version that is right for you:

  • DSTU1 (published September 2014) is mostly obsolete, and the .NET version for this publication is not maintained anymore.
  • DSTU2 (published October 2015) in widespread use, and is not supported by this library anymore since version 2.0.
  • STU3 (published March 2017), mature support by this library and most other tooling on the market.
  • R4 (published January 2019), mature support by this library and fully supported by this library.
  • R4B (published May 2022), the latest release of the FHIR spec and fully supported by this library.

Planned release DSTU2.1 was never published by HL7, but you will still find traces of it, in particular we still keep the NuGet package for it available.

Getting Started

Get started by reading the online documentation. Depending on the version of FHIR you require, you'll find the relevant links to the packages and develop branches in this repository below:

Spec version Git branch Core NuGet
R5 (experimental) https://github.com/FirelyTeam/firely-net-sdk/tree/develop-r5 https://www.nuget.org/packages/Hl7.Fhir.R5
R4B https://github.com/FirelyTeam/firely-net-sdk/tree/develop-r4B https://www.nuget.org/packages/Hl7.Fhir.R4B
R4 https://github.com/FirelyTeam/firely-net-sdk/tree/develop-r4 https://www.nuget.org/packages/Hl7.Fhir.R4
STU3 https://github.com/FirelyTeam/firely-net-sdk/tree/develop-stu3 https://www.nuget.org/packages/Hl7.Fhir.STU3
DSTU2 https://github.com/FirelyTeam/firely-net-sdk/tree/develop https://www.nuget.org/packages/Hl7.Fhir.DSTU2
DSTU1 https://github.com/FirelyTeam/firely-net-sdk/tree/master-dstu1 https://www.nuget.org/packages/Hl7.Fhir.DSTU

Please note that the source code for the Firely .NET SDK is split up into two GitHub repos: one (with the branches listed above) with code that is specific to a FHIR release (this repo), and one that contains the code that is applicable across all FHIR releases (a separate common repository). This second repository is included in the first one using a Git Submodule, so all you have to do is check out the main repo (this one) and learn how to work with Submodules. To clone this repository with submodules, you can do:

git clone --recurse-submodules -j8 https://github.com/FirelyTeam/firely-net-sdk.git .

Please refer to our submodules overview for more details.


Upgrading to 2.x? Breaking changes are listed here.

Going further? See 3.x breaking changes.


We actively monitor the issues coming in through the GitHub repository at https://github.com/FirelyTeam/firely-net-sdk/issues. You are welcome to register your bugs and feature suggestions there. For questions and broader discussions, we use the .NET FHIR Implementers chat on Zulip.


We are welcoming contributors!

If you want to participate in this project, we're using Git Flow for our branch management, so please submit your commits using pull requests on the correct develop-stu3/develop-r4/develop-r4B/develop-r5 branches as mentioned above!

GIT branching strategy

Product Versions
.NET net5.0 net5.0-windows net6.0 net6.0-android net6.0-ios net6.0-maccatalyst net6.0-macos net6.0-tvos net6.0-windows net7.0 net7.0-android net7.0-ios net7.0-maccatalyst net7.0-macos net7.0-tvos net7.0-windows
.NET Core netcoreapp2.0 netcoreapp2.1 netcoreapp2.2 netcoreapp3.0 netcoreapp3.1
.NET Standard netstandard2.0 netstandard2.1
.NET Framework net452 net46 net461 net462 net463 net47 net471 net472 net48
MonoAndroid monoandroid
MonoMac monomac
MonoTouch monotouch
Tizen tizen40 tizen60
Xamarin.iOS xamarinios
Xamarin.Mac xamarinmac
Xamarin.TVOS xamarintvos
Xamarin.WatchOS xamarinwatchos
Compatible target framework(s)
Additional computed target framework(s)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (8)

Showing the top 5 NuGet packages that depend on Hl7.Fhir.Specification.STU3:

Package Downloads

Firely Server (formerly: Vonk) supports building a Facade or a Plugin, see the product pages for Firely Server (https://fire.ly/products/firely-server and FHIR Facade (https://fire.ly/products/fhir-facade). Vonk.Fhir.R3 adds support for working with POCOs from the Firely .NET SDK for FHIR STU3 in your Facade or Plugin. You need Firely Server to use Vonk.Fhir.R3. Go to the product page to download a copy, including an evaluation license. Visit the documentation pages (https://docs.fire.ly/firelyserver/index.html) for documentation and examples on how to build a Facade or a Plugin.


Contains the necessary classes to create a FHIR server. Both the setup classes and FHIR controller is here.


Complements the Spark.Engine library with additional features such as a FHIR service interface and service handling


FhirKhit tools for Fhir STU 3


FhirKhit tools for Fhir STU 3

GitHub repositories (1)

Showing the top 1 popular GitHub repositories that depend on Hl7.Fhir.Specification.STU3:

Repository Stars
A service that implements the FHIR standard
Version Downloads Last updated
4.3.0 5,746 9/22/2022
4.2.1 2,869 8/17/2022
4.2.0 281 8/16/2022
4.1.0 2,486 7/7/2022
4.0.0 3,932 5/10/2022
4.0.0-beta2 86 3/4/2022
4.0.0-beta1 77 2/7/2022
3.8.3 4,544 4/28/2022
3.8.2 5,915 3/28/2022
3.8.1 300 3/4/2022
3.8.0 12,724 1/7/2022
3.7.0 2,072 12/1/2021
3.6.0 11,668 10/15/2021
3.5.0 3,420 9/2/2021
3.4.0 6,779 6/30/2021
3.3.0 2,492 6/2/2021
3.2.0 4,877 5/4/2021
3.1.0 510 4/1/2021
3.0.0 10,005 2/25/2021
2.0.3 3,468 1/26/2021
2.0.2 496 1/22/2021
2.0.1 3,999 11/25/2020
2.0.0 620 11/16/2020
2.0.0-beta2 300 9/22/2020
2.0.0-beta1 373 7/16/2020
1.9.0 17,839 7/23/2020
1.8.0 482 7/2/2020
1.7.0 4,478 5/6/2020
1.6.0 5,797 3/4/2020
1.5.0 2,919 2/4/2020
1.5.0-beta1 420 12/19/2019
1.4.0 10,467 10/10/2019
1.3.0 9,565 7/10/2019
1.2.1 25,387 4/16/2019
1.2.0 2,156 3/29/2019
1.2.0-beta2 463 2/28/2019
1.2.0-beta1 501 2/20/2019
1.1.3 3,868 2/13/2019
1.1.2 10,733 1/31/2019
1.1.1 613 1/30/2019
1.1.0-beta1 566 12/17/2018
1.0.0 1,015 12/17/2018
1.0.0-beta1 553 11/7/2018
0.96.0 13,706 6/6/2018
0.95.0 2,451 4/12/2018
0.94.0 24,019 12/7/2017
0.94.0-beta2 1,313 11/8/2017
0.94.0-beta1 699 11/7/2017
0.93.5 6,328 10/17/2017
0.93.5-beta7 769 9/27/2017
0.93.5-beta6 738 9/5/2017
0.93.5-beta5 732 8/30/2017
0.93.5-beta4 742 8/29/2017
0.93.5-beta3 791 8/3/2017
0.93.5-beta1 768 7/27/2017
0.93.5-alpha1 747 6/15/2017
0.93.4 10,399 5/7/2017
0.93.4-alpha3 775 5/1/2017
0.93.4-alpha2 794 4/26/2017
0.93.4-alpha1 756 4/26/2017
0.93.3 949 4/26/2017
0.93.2 949 4/25/2017
0.93.1 949 4/25/2017
0.93.0 1,030 4/24/2017
0.93.0-alpha4 825 4/12/2017
0.93.0-alpha3 803 4/11/2017
0.93.0-alpha2 737 4/11/2017
0.93.0-alpha1 842 3/23/2017
0.90.6-alpha7 1,516 9/15/2016
0.90.5-alpha4 926 6/7/2016
0.90.5-alpha3 812 4/11/2016