Building the LXQt/Qt6 desktop into an image

The MINIX desktop (wlcompd + LXQt on Qt 6, software-rendered over Wayland) is an out-of-tree stack: glib, D-Bus, Qt 6, KDE Frameworks bits and the LXQt components are CMake/meson/autotools packages, not part of the reachover world. So a normal build.sh release builds the compositor (wlcompd/wlclient, which are reachover programs) but not the desktop apps — they have to be built and installed into DESTDIR as a separate, opt-in stage.

This directory automates that:

desktop-sources.manifest — pinned upstream sources (version + URL + sha256).
build-desktop.sh — fetches, patches, cross-builds and installs the whole stack into a DESTDIR, in dependency order. It is the executable form of the recipes in external/{glib,dbus,qt6,kf6,lxqt,xdg-user-dirs}/README.md.
amd64_cdimage.sh grows an opt-in MKDESKTOP=yes that overlays the result onto the ISO.

Host prerequisites

The cross build needs, on the build host:

meson, ninja, cmake, curl, patch, pkg-config, sha256sum
A host Qt of the same version as qtbase in the manifest (6.11.1). The cross build runs the host moc/rcc/uic via QT_HOST_PATH, and they must match the target Qt version exactly. Set QT_HOST_PATH to that install.

build-desktop.sh checks these and fails loudly if any are missing.

First-time setup: record the checksums

The manifest ships with sha256 = TOFILL. The driver refuses to build against a TOFILL entry (so an upstream content swap can’t slip in unnoticed). Populate them once:

sh releasetools/build-desktop.sh checksums   # fetches each source, prints sha256

Paste the printed column into desktop-sources.manifest and commit.

Building the desktop into DESTDIR

DESTDIR=<…>/destdir.amd64 \
TOOLDIR=<…>/tooldir.<host> \
QT_HOST_PATH=/usr \
sh releasetools/build-desktop.sh

Components build in order (pcre2 → glib → dbus → Qt 6 → qtsvg → ECM/kwindowsystem/ layer-shell-qt → lxqt-build-tools → libqtxdg → liblxqt → the LXQt apps → qterminal → xdg-user-dirs). The driver records everything it installed in <DESKTOP_WORK>/install.list (default <destdir-parent>/desktop-build/).

Putting it on an image — two ways

A. In the sets (installable systems). Install the desktop into DESTDIR between distribution and sets, then the existing minix-base set list packs it automatically (the entries ./usr/bin/startlxqt, lxqt-session, … are already there):

build.sh -m amd64 -O ../build.amd64 -U distribution
sh releasetools/build-desktop.sh                       # into DESTDIR
build.sh -m amd64 -O ../build.amd64 -U sets
bash releasetools/amd64_cdimage.sh

B. Overlay onto the ISO (live CD, no re-sets). Fits the usual two-command flow — build the world/sets normally, then overlay at image time:

build.sh -m amd64 -j24 -O ../build.amd64 -U release
sh releasetools/build-desktop.sh                       # into DESTDIR
MKDESKTOP=yes OBJ=../build.amd64 bash releasetools/amd64_cdimage.sh

MKDESKTOP=yes copies the install.list files straight from DESTDIR into the ISO tree and emits an extra.desktop mtree spec for them. Off by default, so a plain amd64_cdimage.sh is unchanged.

Running it

Boot UEFI (-cpu host, OVMF code+vars pflash) so the GOP framebuffer gives you /dev/fb0, log in, and:

startlxqt        # brings up the fb driver, wlcompd, D-Bus and lxqt-session

See external/lxqt/README.md for the session details and external/qt6/README.md for why everything is linked -static.

Status / things to verify on a real build

build-desktop.sh transcribes the READMEs faithfully, but a few specifics could not be pinned from the tree alone and are marked TODO(verify) in the script — verify them against a known-good build:

pcre2 has no external/pcre2 README; its version (10.44) and flags are inferred.
qtsvg, lxqt-globalkeys, lxqt-menu-data, qtxdg-tools, lxqt-panel and lxqt-session use the shared consumer flag template; the READMEs don’t give their exact -D sets. Confirm any component-specific options.
All manifest URLs follow the standard upstream patterns but are unverified until checksums fetches them successfully.