# Update the Microsoft Quantum Development Kit (QDK)

Learn how to update the Microsoft Quantum Development Kit (QDK) to the latest version.

This article assumes that you already have the QDK installed. If you are installing for the first time, then please refer to the installation guide.

We recommend keeping up to date with the latest QDK release. Follow this update guide to upgrade to the most recent QDK version. The process consists of two parts:

1. Updating your existing Q# files and projects to align your code with any updated syntax.
2. Updating the QDK itself for your chosen development environment.

## Updating Q# Projects

Regardless of whether you are using C# or Python to host Q# operations, follow these instructions to update your Q# projects.

1. First, check that you have the latest version of the .NET Core SDK 3.1. Run the following command in the command prompt:

dotnet --version


Verify the output is 3.1.100 or higher. If not, install the latest version and check again. Then follow the instructions below depending on your setup (Visual Studio, Visual Studio Code, or directly the command line).

### Update Q# projects in Visual Studio

1. Update to the latest version of Visual Studio 2019, see here for instructions.

2. Open your solution in Visual Studio.

3. From the menu, select Build -> Clean Solution.

4. In each of your .csproj files, update the target framework to netcoreapp3.1 (or netstandard2.1 if it is a library project). That is, edit lines of the form:

<TargetFramework>netcoreapp3.1</TargetFramework>


You can find more details on specifying target frameworks here.

5. In each of the .csproj files, set the SDK to Microsoft.Quantum.Sdk, as indicated in the line below. Please notice that the version number should be the latest available, and you can determine it by reviewing the release notes.

<Project Sdk="Microsoft.Quantum.Sdk/0.12.20072031">

6. Save and close all files in your solution.

7. Select Tools -> Command Line -> Developer Command Prompt. Alternatively, you can use the package management console in Visual Studio.

8. For each project in the solution, run the following command to remove this package:

dotnet remove [project_name].csproj package Microsoft.Quantum.Development.Kit


If your projects use any other Microsoft.Quantum or Microsoft.Azure.Quantum packages (e.g. Microsoft.Quantum.Numerics), run the add command for these to update the version used.

dotnet add [project_name].csproj package [package_name]

9. Close the command prompt and select Build -> Build Solution (do not select Rebuild Solution).

You can now skip ahead to update your Visual Studio QDK extension.

### Update Q# projects in Visual Studio Code

1. In Visual Studio Code, open the folder containing the project to update.
2. Select Terminal -> New Terminal.
3. Follow the instructions for updating using the command line (directly below).

### Update Q# projects using the command line

1. Navigate to the folder containing your main project file.

2. Run the following command:

dotnet clean [project_name].csproj

3. Determine the current version of the QDK. To find it, you can review the release notes. The version will be in a format similar to 0.12.20072031.

4. In each of your .csproj files, go through the following steps:

• Update the target framework to netcoreapp3.1 (or netstandard2.1 if it is a library project). That is, edit lines of the form:

<TargetFramework>netcoreapp3.1</TargetFramework>


You can find more details on specifying target frameworks here.

• Replace the reference to the SDK in the project definition. Make sure that the version number corresponds to the value determined in step 3.

<Project Sdk="Microsoft.Quantum.Sdk/0.12.20072031">

• Remove the reference to package Microsoft.Quantum.Development.Kit if present, which will be specified in the following entry:

<PackageReference Include="Microsoft.Quantum.Development.Kit" Version="0.10.1910.3107" />

• Update the version of the all the Microsoft Quantum packages to the most recently released version of the QDK (determined in step 3). Those packages are named with the following patterns:

Microsoft.Quantum.*
Microsoft.Azure.Quantum.*


References to packages have the following format:

<PackageReference Include="Microsoft.Quantum.Compiler" Version="0.12.20072031" />

• Save the updated file.

• Restore the dependencies of the project, by doing the following:

dotnet restore [project_name].csproj

5. Navigate back to the folder containing your main project and run:

dotnet build [project_name].csproj


With your Q# projects now updated, follow the instructions below to update the QDK itself.

## Updating the QDK

The process to update the QDK varies depending on your development language and environment. Select your development environment below.

### Update the qsharp Python package

The update procedure depends on whether you originally installed using conda or using the .NET CLI and pip.

1. Activate the conda environment where you installed the qsharp package, and then run this command to update it:

conda update -c quantum-engineering qsharp

2. Run the following command from the location of your .qs files:

python -c "import qsharp; qsharp.reload()"


You can now use the updated qsharp Python package to run your existing quantum programs.

### Update the IQ# Jupyter kernel

The update procedure depends on whether you originally installed using conda or using the .NET CLI and pip.

1. Activate the conda environment where you installed the qsharp package, and then run this command to update it:

conda update -c quantum-engineering qsharp

2. Run the following command from a cell in each of your existing Q# Jupyter Notebooks:

%workspace reload


You can now use the updated IQ# kernel to run your existing Q# Jupyter Notebooks.

### Update Visual Studio QDK extension

1. Update the Q# Visual Studio extension

Note

The project templates are updated with the extension. The updated templates apply to newly created projects only. The code for your existing projects is not updated when the extension is updated.

### Update VS Code QDK extension

1. Update the Quantum VS Code extension

• Restart VS Code
• Navigate to the Extensions tab
• Select the Microsoft Quantum Development Kit for Visual Studio Code extension

### C#, using the dotnet command-line tool

1. Update the Quantum project templates for .NET

From the command line:

dotnet new -i Microsoft.Quantum.ProjectTemplates


Alternatively, if you intend to use the command line templates, and already have the VS Code QDK extension installed, you can update the project templates from the extension itself:

• Update the QDK extension
• In VS Code, go to View -> Command Palette
• Select Q#: Install command line project templates
• After a few seconds you should get a popup confirming "project templates installed successfully"