1. Download auxiliary sources:

   make get-sources

2. Install build dependencies (package names for Fedora, may differ for others):

   • python

   • zlib-devel

   • xen-devel

   • glib2-devel

   • autoconf

   • automake

   • edk2-tools

   • libtool

   • libseccomp-devel >= 2.3.0

   • pixman-devel

   • xen-devel

   • qubes-gui-common-devel

   • qubes-libvchan-xen-devel

   • bc

   • gcc-plugin-devel

   • gcc-c++

   • quilt

   • xen-runtime

   • busybox

   • dracut

   • inotify-tools

3. Build the thing:

   make -f Makefile.stubdom

The stubdomain consists of two files:

• kernel: build/linux/arch/x86/boot/bzImage
• ramdisk: build/rootfs/stubdom-linux-rootfs

The most interesting things are in rootfs dir:

• gen - script to generate ramdisk, you can add/remove extra binaries here
• init - wrapper script calling qemu and handling interaction with it