# How to build Mozc in Windows

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[![Windows](https://github.com/google/mozc/actions/workflows/windows.yaml/badge.svg)](https://github.com/google/mozc/actions/workflows/windows.yaml)

## Summary

If you are unsure about what the following commands do, please review the
descriptions below to understand the operations before running them.

```
git clone https://github.com/google/mozc.git
cd mozc\src

python build_tools/update_deps.py
python build_tools/build_qt.py --release --confirm_license
bazelisk build --config oss_windows --config release_build package

python build_tools/open.py bazel-bin/win32/installer/Mozc64.msi
```

> [!TIP] You can also download `Mozc64.msi` from GitHub Actions. Check
> [Build with GitHub Actions](#build-with-github-actions) for details.

## Setup

### System Requirements

64-bit Windows 10 or later.

> [!IMPORTANT] Building Mozc on a Windows ARM64 environment is not yet supported
> ([#1296](https://github.com/google/mozc/issues/1296)).

### Software Requirements

Building Mozc on Windows requires the following software.

*   [Visual Studio 2022 Community Edition](https://visualstudio.microsoft.com/downloads/#visual-studio-community-2022)
    with the following components.
    *   Windows 11 SDK
    *   MSVC v143 - VS 2022 C++ x64/x86 build tools (Latest)
    *   C++ ATL for latest v143 build tools (x86 & x64)
*   Python 3.12 or later.
*   `.NET 6` or later (for `dotnet` command).
*   [Bazelisk](https://github.com/bazelbuild/bazelisk)

> [!NOTE] Bazelisk is a wrapper of [Bazel](https://bazel.build) that allows you
> to use a specific version of Bazel.

### Download the repository from GitHub

```
git clone https://github.com/google/mozc.git
cd mozc\src
```

Hereafter you can do all the operations without changing directory.

### Check out additional build dependencies

```
python build_tools/update_deps.py
```

In this step, additional build dependencies will be downloaded, including:

*   [LLVM 20.1.1](https://github.com/llvm/llvm-project/releases/tag/llvmorg-20.1.1)
*   [MSYS2 2025-02-21](https://github.com/msys2/msys2-installer/releases/tag/2025-02-21)
*   [Ninja 1.11.0](https://github.com/ninja-build/ninja/releases/tag/v1.11.0)
*   [Qt 6.9.1](https://download.qt.io/archive/qt/6.8/6.8.0/submodules/qtbase-everywhere-src-6.9.1.tar.xz)
*   [.NET tools](../dotnet-tools.json)

## Build

### Build Qt

```
python build_tools/build_qt.py --release --confirm_license
```

If you would like to manually confirm the Qt license, omit the
`--confirm_license` option.

### Build Mozc

Assuming `bazelisk` is in your `%PATH%`, run the following command to build Mozc
for Windows.

```
bazelisk build --config oss_windows --config release_build package
```

#### Install Mozc

After building Mozc, run the following command to install it:

```
python build_tools/open.py bazel-bin/win32/installer/Mozc64.msi
```

#### Uninstall Mozc

To Uninstall Mozc, press <kbd>Win</kbd>+<kbd>R</kbd> to open the Run dialog and
type and type `ms-settings:appsfeatures-app`, run the following command in the
terminal:

```
start ms-settings:appsfeatures-app
```

Then, uninstall `Mozc` from the list of installed applications.

### Build `Mozc64.msi` for ARM64

To compile executables for ARM64, the following Visual Studio components also
need to be installed:

*   MSVC v143 - VS 2022 C++ ARM64/ARM64EC build tools (Latest)
*   C++ ATL for latest v143 build tools (ARM64/ARM64EC)

To build `Mozc64.msi` for ARM64, run the following commands:

```
python build_tools/build_qt.py --release --confirm_license --target_arch=arm64
bazelisk build --config oss_windows --config release_build package --platforms=//:windows-arm64
```

## Bazel command examples

### Bazel User Guide

*   [Build programs with Bazel](https://bazel.build/run/build)
*   [Commands and Options](https://bazel.build/docs/user-manual)
*   [Write bazelrc configuration files](https://bazel.build/run/bazelrc)

### Run all tests

```
bazelisk test ... --config oss_windows --build_tests_only -c dbg
```

> [!NOTE] `...` means all targets under the current and subdirectories.

--------------------------------------------------------------------------------

## Build with GitHub Actions

GitHub Actions are already set up in
[windows.yaml](../.github/workflows/windows.yaml). With that, you can build and
install Mozc with your own commit as follows.

1.  Fork https://github.com/google/mozc to your GitHub repository.
2.  Push a new commit to your own fork.
3.  Click "Actions" tab on your fork.
4.  Wait until the action triggered by your commit succeeds.
5.  Download `Mozc64.msi` from the action result page.
6.  Install `Mozc64.msi`.

Files on the GitHub Actions page remain available for up to 90 days.

You can also find Mozc Installers for Windows in the google/mozc repository.
Please keep in mind that Mozc is not an officially supported Google product,
even if downloaded from https://github.com/google/mozc/.

1.  Sign in GitHub.
2.  Check
    [recent successful Windows runs](https://github.com/google/mozc/actions/workflows/windows.yaml?query=is%3Asuccess)
    in the google/mozc repository.
3.  Find an action from the last 90 days and click it.
4.  Download `Mozc64.msi` from the action result page if you are using 64-bit
    Windows.

--------------------------------------------------------------------------------

## Build with GYP (deprecated):

⚠️ The GYP build is deprecated and no longer supported.

Please check the previous version for more information.
https://github.com/google/mozc/blob/3.33.6089/docs/build_mozc_in_windows.md#build-with-gyp-maintenance-mode
