LarchBuilding the ISO
mkarchiso, the local AUR repo, and a real gotcha to know about
Requirements
archiso, git, rsync, and base-devel, on an Arch host (or an Arch container).
oh-my-zsh and its plugins are git submodules, clone with --recurse-submodules:
git clone --recurse-submodules git@github.com:larch-os/larch-base.gitBuild
make prepare # once, and whenever AUR packages/submodules bump
make isomake prepare (scripts/prepare-iso.sh) checks out the submodules, copies the zsh plugins into place, builds the AUR-only packages (sddm-silent-theme, redhat-fonts, herdr-bin, paru-bin, k3d-bin) and larch-calamares into a local pacman repo at /tmp/larch-local-repo, and fetches the wallpaper set. Skip it and mkarchiso fails loudly instead of shipping a broken build.
make iso runs sudo mkarchiso -v -w work -o out archiso/releng. Output lands in out/larch-<date>-x86_64.iso.
The incremental-build gotcha
If you're reusing a work/ directory across builds to speed things up, read this before you trust a rebuild.
mkarchiso gates every pipeline step (copying custom airootfs files, building the squashfs, assembling the final ISO) behind marker files it drops directly in the working directory. Once a step's marker exists, mkarchiso skips that step on every future run against the same work/ dir, including the step that copies your changed config files into the build.
The symptom: you edit a file under airootfs/, rerun the same mkarchiso command, and get a new-looking ISO that's actually byte-for-byte the build from before your edit. The tell is a suspiciously short build log (just "Validating options... Done!") and an output file whose modification time didn't move.
Deleting only the top-level marker isn't enough, the sub-steps (airootfs copy, customize script, squashfs, boot files) each have their own markers, and clearing some but not others risks an inconsistent chroot (the customize script running useradd a second time, for instance). The reliable fix is make clean (rm -rf work/) and a full clean rebuild. Since the pacman package cache persists independently of work/, a clean rebuild re-extracts and reinstalls locally without re-downloading anything, so it's not much slower than the incremental path was supposed to be, and it's actually correct.
Testing your build
See Testing in a VM.