Windows

Ruby supports a few native build platforms for Windows.

Building Ruby using Mingw with UCRT

The easiest build environment is just a standard RubyInstaller-Devkit installation and git-for-windows. You might like to use VSCode as an editor.

Build examples

Ruby core development can be done either in Windows cmd like:

ridk install
ridk enable ucrt64

pacman -S --needed %MINGW_PACKAGE_PREFIX%-openssl %MINGW_PACKAGE_PREFIX%-libyaml %MINGW_PACKAGE_PREFIX%-libffi

mkdir c:\work\ruby
cd /d c:\work\ruby

git clone https://github.com/ruby/ruby src

sh ./src/autogen.sh

mkdir build
cd build
sh ../src/configure -C --disable-install-doc
make

or in MSYS2 bash like:

ridk install
ridk enable ucrt64
bash

pacman -S --needed $MINGW_PACKAGE_PREFIX-openssl $MINGW_PACKAGE_PREFIX-libyaml $MINGW_PACKAGE_PREFIX-libffi

mkdir /c/work/ruby
cd /c/work/ruby

git clone https://github.com/ruby/ruby src

./src/autogen.sh
cd build
../src/configure -C --disable-install-doc
make

If you have other MSYS2 environment via other package manager like scoop, you need to specify $MINGW_PACKAGE_PREFIX is mingw-w64-ucrt-x86_64. And you need to add --with-opt-dir option to configure command like:

sh ../../ruby/configure -C --disable-install-doc --with-opt-dir=C:\Users\username\scoop\apps\msys2\current\ucrt64

Building Ruby using Visual C++

Requirement

  1. Windows 10 version 1809 (build 17763)/Windows Server 2019 or later.

  2. Visual C++ 14.15 (Visual Studio 2017 version 15.8) or later.

    Note if you want to build x64 version, use native compiler for x64.

    The minimum requirement is here: * VC++/MSVC build tools on VS 2017 version 15.8 or later. * Windows 10/11 SDK

    You can install Visual Studio Build Tools with winget. win32\install-buildtools.cmd is a batch file to install the minimum requirements excluding the IDE etc.

  3. Please set environment variable INCLUDE, LIB, PATH to run required commands properly from the command line. These are set properly by vsdevcmd.bat or vcvarall*.bat usually. You can run the following command to set them in your command line.

    To native build:

    cmd /k win32\vssetup.cmd

    To cross build arm64 binary:

    cmd /k win32\vssetup.cmd -arch=arm64

    To cross build x64 binary:

    cmd /k win32\vssetup.cmd -arch=x64

    This batch file is a wrapper of vsdevcmd.bat and options are passed to it as-is. win32\vssetup.cmd -help for other command line options.

    Note building ruby requires following commands.

    • nmake

    • cl

    • ml

    • lib

    • dumpbin

  4. If you want to build from GIT source, following commands are required.

    • git

    • ruby 3.1 or later

    You can use scoop to install them like:

    scoop install git ruby

    The windows version of git configured with autocrlf is true. The Ruby test suite may fail with autocrlf set to true. You can set it to false like:

    git config --global core.autocrlf false

  5. You need to install required libraries using vcpkg on directory of ruby repository like:

    vcpkg --triplet x64-windows install

  6. Enable Command Extension of your command line. It's the default behavior of cmd.exe. If you want to enable it explicitly, run cmd.exe with /E:ON option.

  7. Some tests in nmake check create symbolic links. Enable Developer Mode (Settings > System > For developers) so that they do not fail with Permission denied @ rb_file_s_symlink.

  8. If you want to build YJIT, rustc with the x86_64-pc-windows-msvc target is required. YJIT is enabled with --enable-yjit of win32\configure.bat, and is supported only on x64 and only in YJIT's release mode, without the dev and stats builds. --enable-yjit accepts only yes or no. A YJIT build does not install the static library.

  9. If you want to build with clang-cl instead of cl, clang-cl 15 or later is required. It is the "C++ Clang Compiler for Windows" component (Microsoft.VisualStudio.Component.VC.Llvm.Clang) of Visual Studio 2022 version 17.4 or later. win32\vssetup.cmd adds clang-cl to PATH when the component is installed. You can add it to the installed Build Tools with Visual Studio Installer, or from the command line like:

    "%ProgramFiles(x86)%\Microsoft Visual Studio\Installer\setup.exe" modify --installPath "%ProgramFiles(x86)%\Microsoft Visual Studio\18\BuildTools" --add Microsoft.VisualStudio.Component.VC.Llvm.Clang --passive

How to compile and install

  1. Execute win32\configure.bat on your build directory. You can specify the target platform as an argument. For example, run configure --target=i686-mswin32. You can also specify the install directory. For example, run configure --prefix=<install_directory>. Default of the install directory is /usr .

  2. If you want to append to the executable and DLL file names, specify --program-prefix and --program-suffix, like win32\configure.bat --program-suffix=-$(MAJOR)$(MINOR).

    Also, the --install-name and --so-name options specify the exact base names of the executable and DLL files, respectively, like win32\configure.bat --install-name=$(RUBY_BASE_NAME)-$(MAJOR)$(MINOR).

    By default, the name for the executable without a console window is generated from the RUBY_INSTALL_NAME specified as above by replacing ruby with rubyw. If you want to make it different more, modify RUBYW_INSTALL_NAME directly in the Makefile.

  3. You need specify vcpkg directory to use --with-opt-dir option like win32\configure.bat --with-opt-dir=C:/vcpkg_installed/x64-windows

  4. If you want to build with clang-cl, specify CC=clang-cl like win32\configure.bat CC=clang-cl. The installed ruby also uses clang-cl to build extension libraries, so installing gems with C extensions requires clang-cl too.

  5. Run nmake up if you are building from GIT source.

  6. Run nmake

  7. Run nmake prepare-vcpkg with administrator privilege if you need to copy vcpkg installed libraries like libssl-3-x64.dll to the build directory.

  8. Run nmake check

  9. Run nmake install

Build examples

Building with GNU make

nmake cannot run jobs in parallel. win32\configure.bat --with-gnu-make writes GNUmakefile instead of Makefile, so that you can build with make -j. This is experimental, and nmake stays the default.

GNU make 4.4 or later built for native Windows is required. win32\install-gnumake.cmd downloads the GNU make release, verifies its SHA256, builds it with cl, and puts make.exe in .gnumake under the ruby source directory, or in the directory given as its argument.

C:
cd \ruby
win32\install-gnumake.cmd
set PATH=C:\ruby\.gnumake;%PATH%
win32\configure --prefix=/usr/local --with-opt-dir=C:/ruby/vcpkg_installed/x64-windows --with-gnu-make
make -j16
make check
make install

Use make in place of nmake for the other targets in this document too, such as make up, make prepare-vcpkg and make update-vcpkg.

The installed ruby also builds extension libraries with make found in PATH, not with nmake. Before installing gems with C extensions, copy make.exe from .gnumake to a directory in PATH, such as the bin directory of the install directory, since make install does not install it.

Bugs

You can NOT use a path name that contains any white space characters as the ruby source directory, this restriction comes from the behavior of !INCLUDE directives of NMAKE.

You can build ruby in any directory including the source directory, except win32 directory in the source directory. This is restriction originating in the path search method of NMAKE.

Dependency management

Ruby uses vcpkg to manage dependencies on mswin platform.

You can update and install it under the build directory like:

nmake update-vcpkg # Update baseline version of vcpkg
nmake install-vcpkg # Install vcpkg from build directory

Windows Defender Firewall

Some tests listen on all interfaces, and Windows Defender Firewall shows a security alert dialog when an executable at a path it has no rule for does so. If you keep the same build directory, run win32\firewall.cmd there once, and the dialog no longer interrupts the tests. It adds rules that block inbound connections to ruby.exe and rubyw.exe in that directory, so the tests are not exposed to other machines, while connections from the same machine still work.

cd /d D:\build\ruby
C:\src\ruby\win32\firewall.cmd

It restarts itself as administrator when not elevated. It also takes the build directory as an argument. When you no longer need the rules, delete them with -delete.

C:\src\ruby\win32\firewall.cmd -delete D:\build\ruby

If you build in a new worktree for each task, as coding agents often do, every worktree meets the dialog. A post-checkout hook in .git/hooks registers each worktree when git worktree add creates it, before its first build, and skips worktrees that already have the rules. The script elevates itself, so the hook runs without stopping when User Account Control is set to never notify.

#!/bin/sh
top=$(git rev-parse --show-toplevel) || exit 0
fw="$top/win32/firewall.cmd"
[ -f "$fw" ] || exit 0
dir=$(cygpath -w "$top")
netsh advfirewall firewall show rule name="Ruby build directory $dir" >/dev/null 2>&1 && exit 0
cmd //c "$(cygpath -w "$fw")" "$dir" >/dev/null 2>&1
exit 0

Otherwise each new worktree asks for administrator privilege. To avoid that, register once from an elevated prompt a task that runs the script for every worktree with the highest privileges, and replace the cmd line of the hook with schtasks //run //tn ruby-firewall >/dev/null 2>&1. The task runs without asking.

schtasks /create /tn ruby-firewall /sc once /st 00:00 /rl highest /tr "cmd /c for /d %D in (C:\src\worktrees\*) do C:\src\ruby\win32\firewall.cmd %D"

Icons

Any icon files(*.ico) in the build directory, directories specified with icondirs make variable and win32 directory under the ruby source directory will be included in DLL or executable files, according to their base names.

$(RUBY_INSTALL_NAME).ico or ruby.ico   --> $(RUBY_INSTALL_NAME).exe
$(RUBYW_INSTALL_NAME).ico or rubyw.ico --> $(RUBYW_INSTALL_NAME).exe
the others                             --> $(RUBY_SO_NAME).dll

Although no icons are distributed with the ruby source, you can use anything you like. You will be able to find many images by search engines. For example, the following are made from Ruby logo kit: