Japanese input method editors (IMEs) such as Mozc are essential for typing Japanese (yes, skk, anthy and more, but it's out-of-scope in this article). Testing them is a surprisingly fiddly job: an IME behaves differently depending on the desktop environment (GNOME, KDE, Xfce, Budgie), the input framework (ibus, fcitx5, uim), and the Wayland or X11 session. Setting up a fresh VM for every combination from scratch is slow and repetitive, and breaking your host's environment while experimenting is no fun.
virt-japanese-desktop is a small set of toy scripts that solves exactly this
problem. It builds ready-to-use virtual machines - each with a desktop
environment and a Japanese IME already installed and configured - so you can
start typing Japanese within a minute of booting, and throw the whole thing
away without any impact on your host.
What it gives you
A single make command produces a qcow2 image that combines one of four
desktops with one of three IMEs:
| ibus-mozc | fcitx5-mozc | uim-mozc | |
|---|---|---|---|
| GNOME | ✓ | ✓ | ✓ |
| KDE | ✓ | ✓ | ✓ |
| Xfce | ✓ | ✓ | ✓ |
| Budgie | ✓ | ✓ | ✗ |
The one gap - uim on Budgie - is a real technical limitation, not an
oversight: Budgie runs the labwc compositor, which implements
zwp_input_method_v2, while uim-wayland only speaks the older
zwp_input_method_v1 (KWin/Weston). On Budgie you use ibus-mozc or fcitx5-mozc
instead.
All images come with the Japanese locale, fonts, and the Asia/Tokyo time
zone pre-configured, plus the SSH key of your choice. Input switching is wired
up out of the box: Ctrl + Space or Shift + Space for your IMEs to enable it.
The layered-image trick
The core idea is that the images are stacked qcow2 overlay layers, one on top of another:
debian-sid-nocloud-amd64-daily.qcow2 ... base image you download
└─ unstable-japanese-template.qcow2 ... locale, fonts, user, SSH
└─ unstable-<DE>-template.qcow2 ... a desktop environment
└─ unstable-<DE>-<IME>.qcow2 ... desktop + IME, configured
└─ unstable-<DE>-<IME>.workspace.qcow2 ... the image you test in
This makes both building and resetting fast. The first build downloads and customizes the base image and takes a while, but every later step only adds a thin overlay. When a test breaks the VM, you do not rebuild anything - you simply delete the top workspace layer and recreate it. That is all it takes to return to a pristine state:
rm /tmp/unstable-gnome-ibus-mozc.workspace.qcow2
make gnome-ibus-mozc
The images reference their backing files by relative path, so you can move an entire stack anywhere you like as long as the images stay together.
A platform for experimenting with bleeding-edge IMEs
The base system is Debian unstable (sid), and the experimental
repository is already added. That makes the project a convenient platform for
testing not just the IME packages in sid but also the ones still being
developed in experimental - exactly what the project was built for.
The keyboard layout of the VM follows the layout of your host (read from
/etc/default/keyboard, with a fallback chain to localectl and finally
us).
Quick start
# 1. Install the tools (Debian/Ubuntu example) sudo apt install qemu-utils libguestfs-tools virt-install curl # 2. Save your SSH public key curl --location https://github.com/USERNAME.keys --output pubkey.pub # 3. Download the base Debian sid image make download # 4. Build a desktop + IME (first build takes a while) make gnome-ibus-mozc # 5. Start it as a VM (needs the libvirt daemon, qemu:///system) ./scripts/make-virsh-image.sh virt-gnome-ibus-mozc /tmp/unstable-gnome-ibus-mozc.workspace.qcow2
Log in as debian (password debian) and press Ctrl + Space (Shift + Space) to start
typing Japanese. The VM is registered in libvirt, so you can manage it with
virsh or virt-manager - handy for opening the SPICE console or restarting
the machine after a test.
Status
The project is still in the proof-of-concept phase, and it is developed mainly to test Mozc and other IMEs across desktops and input frameworks.
If you regularly test Japanese IMEs - give it a try.
