| --- | |
| title: 'Installing Bazel on Windows' | |
| --- | |
| This page describes the requirements and steps to install Bazel on Windows. | |
| It also includes troubleshooting and other ways to install Bazel, such as | |
| using Chocolatey or Scoop. | |
| ## Installing Bazel {#installing-bazel} | |
| This section covers the prerequisites, environment setup, and detailed | |
| steps during installation on Windows. | |
| ### Check your system {#check-system} | |
| Recommended: 64 bit Windows 10, version 1703 (Creators Update) or newer | |
| To check your Windows version: | |
| * Click the Start button. | |
| * Type `winver` in the search box and press Enter. | |
| * You should see the About Windows box with your Windows version information. | |
| ### Install the prerequisites {#install-prerequisites} | |
| * [Microsoft Visual C++ Redistributable](https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170) | |
| ### Download Bazel {#download-bazel} | |
| *Recommended*: [Use Bazelisk](/versions/9.3.0/install/bazelisk) | |
| Alternatively you can: | |
| * [Download the Bazel binary (`bazel-<var>version</var>-windows-x86_64.exe`) from | |
| GitHub](https://github.com/bazelbuild/bazel/releases). | |
| * [Install Bazel from Chocolatey](#chocolately) | |
| * [Install Bazel from Scoop](#scoop) | |
| * [Build Bazel from source](/versions/9.3.0/install/compile-source) | |
| ### Set up your environment {#set-environment} | |
| To make Bazel easily accessible from command prompts or PowerShell by default, you can rename the Bazel binary to `bazel.exe` and add it to your default paths. | |
| ```posix-terminal | |
| set PATH=%PATH%;<var>path to the Bazel binary</var> | |
| ``` | |
| You can also change your system `PATH` environment variable to make it permanent. Check out how to [set environment variables](/versions/9.3.0/configure/windows#set-environment-variables). | |
| ### Done {#done} | |
| "Success: You've installed Bazel." | |
| To check the installation is correct, try to run: | |
| ```posix-terminal | |
| bazel <var>version</var> | |
| ``` | |
| Next, you can check out more tips and guidance here: | |
| * [Installing compilers and language runtimes](#install-compilers) | |
| * [Troubleshooting](#troubleshooting) | |
| * [Best practices on Windows](/versions/9.3.0/configure/windows#best-practices) | |
| * [Tutorials](/versions/9.3.0/start/#tutorials) | |
| ## Installing compilers and language runtimes {#install-compilers} | |
| Depending on which languages you want to build, you will need: | |
| * [MSYS2 x86_64](https://www.msys2.org/) | |
| MSYS2 is a software distro and building platform for Windows. It contains Bash and common Unix | |
| tools (like `grep`, `tar`, `git`). | |
| You will need MSYS2 to build, test, or run targets that depend on Bash. Typically these are | |
| `genrule`, `sh_binary`, `sh_test`, but there may be more (such as Starlark rules). Bazel shows an | |
| error if a build target needs Bash but Bazel could not locate it. | |
| * Common MSYS2 packages | |
| You will likely need these to build and run targets that depend on Bash. MSYS2 does not install | |
| these tools by default, so you need to install them manually. Projects that depend on Bash tools in `PATH` need this step (for example TensorFlow). | |
| Open the MSYS2 terminal and run this command: | |
| ```posix-terminal | |
| pacman -S zip unzip patch diffutils git | |
| ``` | |
| Optional: If you want to use Bazel from CMD or Powershell and still be able | |
| to use Bash tools, make sure to add | |
| `<var>MSYS2_INSTALL_PATH</var>/usr/bin` to your | |
| `PATH` environment variable. | |
| * [Build Tools for Visual Studio 2019](https://aka.ms/buildtools)<a name="install-vc"></a> | |
| You will need this to build C++ code on Windows. | |
| Also supported: | |
| * Visual C++ Build Tools 2017 (or newer) and Windows 10 SDK | |
| * [Java SE Development Kit 11 (JDK) for Windows x64](https://www.oracle.com/java/technologies/javase-jdk11-downloads.html)<a name="install-jdk"></a> | |
| You will need this to build Java code on Windows. | |
| Also supported: Java 8, 9, and 10 | |
| * [Python 3.6 for Windows x86-64](https://www.python.org/downloads/windows/)<a name="install-python"></a> | |
| You will need this to build Python code on Windows. | |
| Also supported: Python 2.7 or newer for Windows x86-64 | |
| ## Troubleshooting {#troubleshooting} | |
| ### Bazel does not find Bash or bash.exe | |
| **Possible reasons**: | |
| * you installed MSYS2 not under the default install path | |
| * you installed MSYS2 i686 instead of MSYS2 x86\_64 | |
| * you installed MSYS instead of MSYS2 | |
| **Solution**: | |
| Ensure you installed MSYS2 x86\_64. | |
| If that doesn't help: | |
| 1. Go to Start Menu > Settings. | |
| 2. Find the setting "Edit environment variables for your account" | |
| 3. Look at the list on the top ("User variables for <username>"), and click the "New..." | |
| button below it. | |
| 4. For "Variable name", enter `BAZEL_SH` | |
| 5. Click "Browse File..." | |
| 6. Navigate to the MSYS2 directory, then to `usr\bin` below it. | |
| For example, this might be `C:\msys64\usr\bin` on your system. | |
| 7. Select the `bash.exe` or `bash` file and click OK | |
| 8. The "Variable value" field now has the path to `bash.exe`. Click OK to close the window. | |
| 9. Done. | |
| If you open a new cmd.exe or PowerShell terminal and run Bazel now, it will find Bash. | |
| ### Bazel does not find Visual Studio or Visual C++ | |
| **Possible reasons**: | |
| * you installed multiple versions of Visual Studio | |
| * you installed and removed various versions of Visual Studio | |
| * you installed various versions of the Windows SDK | |
| * you installed Visual Studio not under the default install path | |
| **Solution**: | |
| 1. Go to Start Menu > Settings. | |
| 2. Find the setting "Edit environment variables for your account" | |
| 3. Look at the list on the top ("User variables for <username>"), and click the "New..." | |
| button below it. | |
| 4. For "Variable name", enter `BAZEL_VC` | |
| 5. Click "Browse Directory..." | |
| 6. Navigate to the `VC` directory of Visual Studio. | |
| For example, this might be `C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC` | |
| on your system. | |
| 7. Select the `VC` folder and click OK | |
| 8. The "Variable value" field now has the path to `VC`. Click OK to close the window. | |
| 9. Done. | |
| If you open a new cmd.exe or PowerShell terminal and run Bazel now, it will find Visual C++. | |
| ## Other ways to install Bazel {#install-options} | |
| ### Using Chocolatey {#chocolately} | |
| 1. Install the [Chocolatey](https://chocolatey.org) package manager | |
| 2. Install the Bazel package: | |
| ```posix-terminal | |
| choco install bazel | |
| ``` | |
| This command will install the latest available version of Bazel and | |
| its dependencies, such as the MSYS2 shell. This will not install Visual C++ | |
| though. | |
| See [Chocolatey installation and package maintenance | |
| guide](/versions/9.3.0/contribute/windows-chocolatey-maintenance) for more | |
| information about the Chocolatey package. | |
| ### Using Scoop {#scoop} | |
| 1. Install the [Scoop](https://scoop.sh/) package manager using the following PowerShell command: | |
| ```posix-terminal | |
| iex (new-object net.webclient).downloadstring('https://get.scoop.sh') | |
| ``` | |
| 2. Install the Bazel package: | |
| ```posix-terminal | |
| scoop install bazel | |
| ``` | |
| See [Scoop installation and package maintenance | |
| guide](/versions/9.3.0/contribute/windows-scoop-maintenance) for more | |
| information about the Scoop package. | |
| ### Build from source {#build-from-source} | |
| To build Bazel from scratch instead of installing, see [Compiling from source](/versions/9.3.0/install/compile-source). |