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+Building Bazel on Windows
+=========================
+
+TODO(bazel-team): Publish this file when Windows support is mature enough.
+
+Warning: Windows support on Bazel is still at a very early stage, many things
+will not work.
+
+Since Bazel is written in Java, you will need a recent
+[JDK](http://www.oracle.com/technetwork/java/javase/downloads/index.html).
+
+The Windows build process uses MSYS2, a POSIX-like environment on Windows. Grab
+the [installer](http://sourceforge.net/projects/msys2/files/Base/x86_64/)
+or an archived version and install.
+
+Next, open an MSYS2 shell (not the mingw32 or the mingw64 shell) either through
+a shortcut or by running the `msys2_shell.bat`. Install the dependencies:
+
+    pacman -S libarchive-devel gcc mingw-w64-x86_64-gcc zip unzip git
+
+The msys2 gcc will be used for building Bazel itself, the mingw-w64 gcc will
+be used by Bazel for building C++.
+
+Grab the Bazel source code:
+
+    git clone https://github.com/google/bazel.git
+
+Then, to build:
+
+    cd bazel && ./compile.sh
+
+If all goes well, you should find the binary in `output/bazel`.
+
+
+Running Bazel on Windows
+========================
+
+Running Bazel on Windows requires a few additional steps due to the differences
+between the native POSIX environment and the Windows environment.
+
+First, since Blaze uses symlinks, the current Windows user needs to have the
+permission to create symlinks. This permission is off by default for
+non-administrator users. The easiest workaround is to run the msys2 shell
+as administrator (right click shortcut -> Run As Administrator).
+
+Second, you need to set some environment variables:
+
+    export MSYS=winsymlinks:nativestrict  # Enable symlink support in msys2.
+    export BAZEL_SH="C:/msys64/usr/bin/bash"
+    export JAVA_HOME="$(ls -d C:/Program\ Files/Java/jdk* | sort | tail -n 1)"
+
+Third, you need to set some Bazel options. It's easiest to put them into your
+`.bazelrc`:
+
+    cat > ~/.bazelrc << EOF
+    startup --batch  # Server mode is not yet supported on Windows
+    build --compiler=windows_msys64_mingw64
+    build --nobuild_runfile_links  # Not ported to Windows yet.
+    EOF
+
+This should be enough to run Bazel:
+
+    cd base_workspace &&
+    ../output/bazel build //cpp:hello-world