Develop a web extension

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Extensions enhance Azure DevOps and Team Foundation Server (TFS) with new web experiences, dashboard widgets, build tasks, and more. Extensions are developed using standard technologies like HTML, JavaScript, and CSS. They're packaged and published to the Visual Studio Marketplace, and can then be installed into an organization.


Check out our newest documentation on extension development using the Azure DevOps Extension SDK.

This tutorial guides you through creating your first web extension, which includes the following tasks.

  • Install the required tools
  • Read a local directory for your extension
  • Create an extension manifest file and hub contribution
  • Package and publish your extension to the Marketplace
  • Test your extension in an organization
Need help? Post questions to the Azure DevOps Services Developer Community.


You must have the following permission and installations.

  • You're an organization Owner.

    If you don't have a personal organization, you can create an organization for free.

  • Install Node.js.

  • Install the extension packaging tool (TFX) by running npm install -g tfx-cli from a command prompt.

Create a directory and manifest

An extension is composed of a set of files that includes a required manifest file. You package it into a .vsix file and publish to the Visual Studio Marketplace.

  1. Create a directory to hold the files needed for your extension:

    md my-first-extension
  2. From this directory, initialize a new NPM package manifest:

    npm init -y

    This file describes the libraries required by your extension.

  3. Install the Microsoft VSS Web Extension SDK package and save it to your NPM package manifest:

    npm install vss-web-extension-sdk --save

    This SDK includes a JavaScript library that provides APIs required for communicating with the page your extension is embedded in.

  4. Create an extension manifest file named vss-extension.json at the root of your extension directory with the following content:

        "manifestVersion": 1,
        "id": "my-first-extension",
        "publisher": "",
        "version": "1.0.0",
        "name": "My First Extension",
        "description": "A sample Visual Studio Services extension",
        "public": false,
        "categories": ["Azure Repos"],
        "targets": [
                "id": "Microsoft.VisualStudio.Services"
        "contributions": [
                "id": "my-hub",
                "type": "ms.vss-web.hub",
                "targets": [
                "properties": {
                    "name": "My Hub",
                    "uri": "my-hub.html"
        "files": [
                "path": "my-hub.html",
                "addressable": true
                "path": "node_modules/vss-web-extension-sdk/lib",
                "addressable": true,
                "packagePath": "lib"


    The public property controls whether the extension is visible to everyone on the Visual Studio Marketplace. During development you should keep your extensions private.

  5. Create a file named my-hub.html at the root of your extension directory with the following content:

    <!DOCTYPE html>
    <html xmlns="">
        <script src="lib/VSS.SDK.min.js"></script>
            body {
                background-color: rgb(0, 67, 117);
                color: white;
                margin: 10px;    
                font-family: "Segoe UI VSS (Regular)","-apple-system",BlinkMacSystemFont,"Segoe UI",sans-serif;
        <script type="text/javascript">
            VSS.ready(function() {
                document.getElementById("name").innerText = VSS.getWebContext();
        <h1>Hello, <span id="name"></span></h1>

    This is the content for the view (also known as a hub) contributed into the Azure DevOps web experience.

  6. At this point, your extension directory should look like this:

    |-- my-hub.html
    |-- node_modules
        |-- @types
        |-- vss-web-extension-sdk
    |-- package.json
    |-- vss-extension.json

You're now ready to package, publish, and test your extension.

Package and publish your extension

Create a publisher

All extensions, including extensions from Microsoft, live under a publisher. Anyone can create a publisher and publish extensions under it. You can also give other people access to your publisher if a team is developing the extension.

  1. Sign in to the Visual Studio Marketplace management portal

  2. If you don't already have a publisher, you'll be prompted to create one.

  3. In the Create Publisher form, enter your name in the publisher name field. The ID field should get set automatically based on your name:

    Create publisher.


    Remember the ID. You need to set it in the manifest file of your extension.

You're now ready to package your extension and publish (upload) it to the Marketplace. Keep this browser window open as you'll need to return here after you package your extension.

Package your extension

  1. Open your extension manifest file (vss-extension.json) and set the value of the publisher field to the ID of your publisher. For example:

        "id": "my-first-extension",
        "publisher": "AnnetteNielsen",
  2. TFX requires the VSS Web Extensions SDK. If you haven't already installed it, open a command prompt and run this command:

    npm install vss-web-extension-sdk --save
  3. From a command prompt, run the TFX tool's packaging command from your extension directory:

    tfx extension create

    When it's completed, you see a message indicating your extension has been successfully packaged:

    === Completed operation: create extension ===
    - VSIX: C:\my-first-extension\
    - Extension ID: my-first-extension
    - Extension Version: 1.0.0
    - Publisher: AnnetteNielsen

Upload your extension

  1. From the management portal, select your publisher from the drop-down at the top of the page.

  2. Tap New Extension and select Azure DevOps:

    Upload new extension for Azure DevOps or TFS

  3. Select the link in the center of the Upload dialog to open a browse dialog.

  4. Locate the .vsix file (created in the packaging step above) and choose Upload:

    Upload new extension for Azure DevOps or TFS

  5. After a few seconds, your extension appears in the list of published extensions. Don't worry, the extension is only visible to you.

    Upload new extension for Azure DevOps or TFS

Install your extension

To test an extension, it must be installed to an organization in Azure DevOps or TFS. Installing requires being the owner of the organization (or having the necessary permissions). Because your extension is private, it must first be shared with the organization you want to install it to.

  1. From the management portal, select your extension from the list, right-click, and choose Share/Unshare.

    Upload new extension for Azure DevOps or TFS

  2. Select the + Organization button, enter the name of your organization, and press enter.

    Share with account

  3. Select the X to close this panel.

Your extension can now be installed into this organization.

  1. Right-click your extension and choose View Extension to open its details page

    Details page


    Because your extension is private, only you (as the publisher of the extension) and any member of the organization it is shared with can see this page.

  2. Select Get it free to start the installation process. The organization you shared the extension with should be selected:

    Install extension panel

  3. Select Install.

Congratulations! Your extension is now installed into an organization and is ready to be tested.

Try your extension

Your extension contributed a view named "My Hub" to the project-level Code area. Let's navigate to it.

  1. Tap the Proceed to organization button at the end of the installation wizard to navigate to the home page of the organization the extension was installed to ({organization}).

  2. Select any of the projects listed to navigate into it:

    Install extension panel

    If there are no projects in your organization, you are prompted to create one.

  3. Navigate to the Code area and then to the hub contributed by your extension (My Hub):

    My hub

Debugging your extension

To debug the extension using Visual Studio or Browser Developer Tools and speed up the development without redeploying extension each time you change source code, you need change manifest adding baseUri property:

    "baseUri": "https://localhost:44300",

Changing the manifest tells Azure DevOps to load the extension from your local web server instance (for example, IISExpress in Visual Studio). After you change the manifest, deploy and install this debugging extension only once.


You have to run your local web server in SSL mode, because Azure DevOps and TFS demand that web page is served from a secure source otherwise you obtain an error in browser console during the extension IFRAME loading.

Next steps