diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000..fa7adc7
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+3.3.5
diff --git a/Rakefile b/Rakefile
new file mode 100644
index 0000000..e69de29
diff --git a/rakelib/cross.rake b/rakelib/cross.rake
new file mode 100644
index 0000000..3de7d79
--- /dev/null
+++ b/rakelib/cross.rake
@@ -0,0 +1,307 @@
+require 'pathname'
+require 'uri'
+require 'net/http'
+require 'rake/clean'
+require 'open3'
+require 'etc'
+
+GCC_VERSION = "14.2.0"
+BINUTILS_VERSION = '2.43.1'
+GLIBC_VERSION = '2.40'
+KERNEL_VERSION = '5.15.166'
+
+TMP = Pathname.new('./build')
+
+CLEAN.include TMP
+
+class BuildTarget
+  attr_accessor(:build, :gcc, :target, :tmp)
+
+  def gxx
+    @gcc.gsub 'c', '+'
+  end
+
+  def sysroot
+    tmp + 'sysroot'
+  end
+
+  def rootfs
+    tmp + 'rootfs'
+  end
+
+  def tools
+    tmp + 'tools'
+  end
+end
+
+def gcc_verbose(gcc_binary)
+  read, write = IO.pipe
+  sh({'LANG' => 'C'}, gcc_binary, '--verbose', err: write)
+  write.close
+  output = read.read
+  read.close
+  output
+end
+
+def find_build_target(gcc_version, task)
+  gcc_binary = 'gcc'
+  output = gcc_verbose gcc_binary
+
+  if output.start_with? 'Apple clang'
+    gcc_binary = "gcc-#{gcc_version.split('.').first}"
+    output = gcc_verbose gcc_binary
+  end
+  result = output
+    .lines
+    .each_with_object(BuildTarget.new) do |line, accumulator|
+      if line.start_with? 'Target: '
+        accumulator.build = line.split(' ').last.strip
+      elsif line.start_with? 'COLLECT_GCC'
+        accumulator.gcc = line.split('=').last.strip
+      end
+    end
+  result.tmp = TMP
+  task.with_defaults target: 'riscv32-unknown-linux-gnu'
+  result.target = task[:target]
+  result
+end
+
+def download_and_unarchive(url, target)
+  case File.extname url.path
+  when '.bz2'
+    archive_type = '-j'
+    root_directory = File.basename url.path, '.tar.bz2'
+  when '.xz'
+    archive_type = '-J'
+    root_directory = File.basename url.path, '.tar.xz'
+  else
+    raise "Unsupported archive type #{url.path}."
+  end
+
+  Net::HTTP.start(url.host, url.port, use_ssl: url.scheme == 'https') do |http|
+    request = Net::HTTP::Get.new url.request_uri
+
+    http.request request do |response|
+      case response
+      when Net::HTTPRedirection
+        download_and_unarchive URI.parse(response['location'])
+      when Net::HTTPSuccess
+        Open3.popen2 'tar', '-C', target.to_path, archive_type, '-xv' do |stdin, stdout, wait_thread|
+          stdout.close
+
+          response.read_body do |chunk|
+            stdin.write chunk
+          end
+        end
+      else
+        response.error!
+      end
+    end
+  end
+  target + root_directory
+end
+
+namespace :cross do
+  desc 'Build cross binutils'
+  task :binutils, [:target] do |_, args|
+    options = find_build_target GCC_VERSION, args
+    options.tools.mkpath
+    source_directory = download_and_unarchive(
+      URI.parse("https://ftp.gnu.org/gnu/binutils/binutils-#{BINUTILS_VERSION}.tar.xz"),
+      options.tools)
+
+    cwd = source_directory.dirname + 'build-binutils'
+    cwd.mkpath
+    options.rootfs.mkpath
+
+    env = {
+     'CC' => options.gcc,
+     'CXX' => options.gxx
+    }
+    configure_options = [
+      "--prefix=#{options.rootfs.realpath}",
+      "--target=#{options.target}",
+      '--disable-nls',
+      '--enable-gprofng=no',
+      '--disable-werror',
+      '--enable-default-hash-style=gnu',
+      '--disable-libquadmath'
+    ]
+    configure = source_directory.relative_path_from(cwd) + 'configure'
+    sh env, configure.to_path, *configure_options, chdir: cwd.to_path
+    sh env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path
+    sh env, 'make', 'install', chdir: cwd.to_path
+  end
+
+  desc 'Build stage 1 GCC'
+  task :gcc1, [:target] do |_, args|
+    options = find_build_target GCC_VERSION, args
+    options.tools.mkpath
+    source_directory = download_and_unarchive(
+      URI.parse("https://gcc.gnu.org/pub/gcc/releases/gcc-#{GCC_VERSION}/gcc-#{GCC_VERSION}.tar.xz"),
+      options.tools)
+
+    cwd = source_directory.dirname + 'build-gcc'
+    cwd.mkpath
+    options.rootfs.mkpath
+    options.sysroot.mkpath
+
+    sh 'contrib/download_prerequisites', chdir: source_directory.to_path
+    configure_options = [
+      "--prefix=#{options.rootfs.realpath}",
+      "--with-sysroot=#{options.sysroot.realpath}",
+      '--enable-languages=c,c++',
+      '--disable-shared',
+      '--with-arch=rv32imafdc',
+      '--with-abi=ilp32d',
+      '--with-tune=rocket',
+      '--with-isa-spec=20191213',
+      '--disable-bootstrap',
+      '--disable-multilib',
+      '--disable-libmudflap',
+      '--disable-libssp',
+      '--disable-libquadmath',
+      '--disable-libsanitizer',
+      '--disable-threads',
+      '--disable-libatomic',
+      '--disable-libgomp',
+      '--disable-libvtv',
+      '--disable-libstdcxx',
+      '--disable-nls',
+      '--with-newlib',
+      '--without-headers',
+      "--target=#{options.target}",
+      "--build=#{options.build}",
+      "--host=#{options.build}"
+    ]
+    flags = '-O2 -fPIC'
+    env = {
+      'CC' => options.gcc,
+      'CXX' => options.gxx,
+      'CFLAGS' => flags,
+      'CXXFLAGS' => flags,
+      'PATH' => "#{options.rootfs.realpath + 'bin'}:#{ENV['PATH']}"
+    }
+    configure = source_directory.relative_path_from(cwd) + 'configure'
+    sh env, configure.to_path, *configure_options, chdir: cwd.to_path
+    sh env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path
+    sh env, 'make', 'install', chdir: cwd.to_path
+  end
+
+  desc 'Copy glibc headers'
+  task :headers, [:target] do |_, args|
+    options = find_build_target GCC_VERSION, args
+    options.tools.mkpath
+
+    source_directory = download_and_unarchive(
+      URI.parse("https://ftp.gnu.org/gnu/glibc/glibc-#{GLIBC_VERSION}.tar.xz"),
+      options.tools)
+    include_directory = options.tools + 'include'
+
+    include_directory.mkpath
+    cp (source_directory + 'elf/elf.h'), (include_directory + 'elf.h')
+  end
+
+  desc 'Build linux kernel'
+  task :kernel, [:target] do |_, args|
+    options = find_build_target GCC_VERSION, args
+    options.tools.mkpath
+
+    cwd = download_and_unarchive(
+      URI.parse("https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-#{KERNEL_VERSION}.tar.xz"),
+      options.tools)
+
+    env = {
+      'CROSS_COMPILE' => "#{options.target}-",
+      'ARCH' => 'riscv',
+      'PATH' => "#{options.rootfs.realpath + 'bin'}:#{ENV['PATH']}",
+      'HOSTCFLAGS' => "-D_UUID_T -D__GETHOSTUUID_H -I#{options.tools.realpath + 'include'}"
+    }
+    sh env, 'make', 'rv32_defconfig', chdir: cwd.to_path
+    sh env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path
+    sh env, 'make', 'headers', chdir: cwd.to_path
+
+    user_directory = options.sysroot + 'usr'
+
+    user_directory.mkpath
+    cp_r (cwd + 'usr/include'), (user_directory + 'include')
+  end
+
+  desc 'Build glibc'
+  task :glibc, [:target] do |_, args|
+    options = find_build_target GCC_VERSION, args
+    source_directory = options.tools + "glibc-#{GLIBC_VERSION}"
+    configure_options = [
+      '--prefix=/usr',
+      "--host=#{options.target}",
+      "--target=#{options.target}",
+      "--build=#{options.build}",
+      "--enable-kernel=#{KERNEL_VERSION}",
+      "--with-headers=#{options.sysroot.realpath + 'usr/include'}",
+      '--disable-nscd',
+      '--disable-libquadmath',
+      '--disable-libitm',
+      '--disable-werror',
+      'libc_cv_forced_unwind=yes'
+    ]
+    bin = options.rootfs.realpath + 'bin'
+    env = {
+      'PATH' => "#{bin}:#{ENV['PATH']}",
+      'MAKE' => 'make' # Otherwise it uses gnumake which can be different and too old.
+    }
+    cwd = source_directory.dirname + 'build-glibc'
+    cwd.mkpath
+
+    configure = source_directory.relative_path_from(cwd) +'./configure'
+    sh env, configure.to_path, *configure_options, chdir: cwd.to_path
+    sh env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path
+    sh env, 'make', "install_root=#{options.sysroot.realpath}", 'install', chdir: cwd.to_path
+  end
+
+  desc 'Build stage 2 GCC'
+  task :gcc2, [:target] do |_, args|
+    options = find_build_target GCC_VERSION, args
+    source_directory = options.tools + "gcc-#{GCC_VERSION}"
+    cwd = options.tools + 'build-gcc'
+
+    rm_rf cwd
+    cwd.mkpath
+
+    configure_options = [
+      "--prefix=#{options.rootfs.realpath}",
+      "--with-sysroot=#{options.sysroot.realpath}",
+      '--enable-languages=c,c++,lto',
+      '--enable-lto',
+      '--enable-shared',
+      '--with-arch=rv32imafdc',
+      '--with-abi=ilp32d',
+      '--with-tune=rocket',
+      '--with-isa-spec=20191213',
+      '--disable-bootstrap',
+      '--disable-multilib',
+      '--enable-checking=release',
+      '--disable-libssp',
+      '--disable-libquadmath',
+      '--enable-threads=posix',
+      '--with-default-libstdcxx-abi=new',
+      '--disable-nls',
+      "--target=#{options.target}",
+      "--build=#{options.build}",
+      "--host=#{options.build}"
+
+    ]
+    flags = '-O2 -fPIC'
+    env = {
+      'CFLAGS' => flags,
+      'CXXFLAGS' => flags,
+      'PATH' => "#{options.rootfs.realpath + 'bin'}:#{ENV['PATH']}"
+    }
+    configure = source_directory.relative_path_from(cwd) + 'configure'
+    sh env, configure.to_path, *configure_options, chdir: cwd.to_path
+    sh env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path
+    sh env, 'make', 'install', chdir: cwd.to_path
+  end
+end
+
+task cross: ['cross:binutils', 'cross:gcc1', 'cross:headers', 'cross:kernel', 'cross:glibc', 'cross:gcc2'] do
+end