Mika Linux — base ISO

The build profile for Mika Linux: an Arch-based live ISO with the KDE Plasma desktop and the Calamares graphical installer, built with archiso (mkarchiso). Boot the ISO and you get a live Plasma session that auto-launches Calamares to install Mika to disk.

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For users — make a bootable USB

1. Build the ISO (see Build) or download one from Releases. It lands in out/.
2. Flash it to a USB stick — replace /dev/sdX with your stick:

lsblk -d -o NAME,SIZE,TRAN,MODEL          # find your USB (TRAN=usb)
sudo umount /dev/sdX* 2>/dev/null
sudo dd if="out/Mika Linux-"*.iso of=/dev/sdX bs=4M status=progress oflag=direct conv=fsync
sync

Warning

dd overwrites the whole disk. The wrong /dev/sdX will wipe it — confirm with lsblk first (your USB is the one with TRAN=usb and the right size).

3. Boot it and run the installer: Erase disk → create your user → Install.

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Build

Needs archiso + git:

sudo pacman -S --needed archiso git
git clone https://github.com/Mika-Project/base-iso
cd base-iso
sudo mkarchiso -v -w /var/tmp/mika-work -o out .

The finished ISO is written to out/. -w sets the work directory — keep it on disk (not a RAM-backed /tmp) on low-RAM machines.

Important

mkarchiso needs a fresh work dir each run. Delete it first (sudo rm -rf /var/tmp/mika-work), or build with -r to auto-remove it: sudo mkarchiso -v -r .

Note

This repo already ships airootfs/etc/localtime. Only if a build complains about a missing localtime, recreate it: ln -sf /usr/share/zoneinfo/UTC airootfs/etc/localtime.

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Test it in QEMU (no USB needed)

Interactive — a QEMU window you click through by hand:

sudo pacman -S --needed qemu-desktop edk2-ovmf
run_archiso -u -i out/*.iso          # UEFI
run_archiso    -i out/*.iso          # BIOS / MBR

Automated / headless — proves the ISO boots and installs into a system that itself boots, entirely over a serial console (full docs in scripts/test/README.md):

scripts/test/boot-test.sh uefi       # boot smoke test          (bios | uefi | both)
scripts/test/install-test.sh uefi    # scripted install, then boot the installed disk
scripts/test/verify-mika-run.sh uefi # boot to desktop + verify Calamares loads every module

On a RAM-tight machine (e.g. 15 GB, no swap) prefix any of them with VM_MEM=2048.

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Repo layout (for contributors)

Path	What it is
airootfs/	The live/installed root filesystem overlay — configs, users, /etc/skel, branding.
airootfs/etc/calamares/	The Calamares installer config: settings.conf (module sequence) + modules/*.conf.
airootfs/etc/sddm.conf.d/	Display manager + live autologin.
packages.x86_64	Every package installed into the ISO.
profiledef.sh	archiso profile — ISO name/label and file_permissions (see gotchas).
pacman.conf	Pacman config used during the build; points at the custom mikalinux-repo.
scripts/test/	The headless QEMU build → boot → install test harness.

Mika pulls a few packages it can't get from official Arch (the Calamares build and some soname shims) from its own package repo, mikalinux-repo.

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Gotchas worth knowing (these have bitten us)

• profiledef.sh file_permissions resets every file to 0644. Any custom script that must stay executable in the ISO — e.g. usr/local/bin/mika-grub-install (Calamares' GRUB wrapper) — must be listed there with mode 755, or the install aborts with "permission denied". A trailing slash on a directory entry (["/home/mika/"]=...) makes the chown recursive.
• Calamares mount.conf options: must be a YAML list, never a bare scalar. options: bind is mangled into the invalid mount option b,i,n,d (the /dev mount then fails and the install dies at mkinitcpio). Write options: [ bind ].
• services-systemd.conf mandatory: true aborts the install if the unit/package isn't present — only mark a service mandatory if its package is in packages.x86_64.

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Continuous integration

.github/workflows/iso-test.yml builds the ISO and runs the headless boot + install tests on a runner, so a change that breaks the build or the install is caught automatically before it ships.