The Cosmic desktop environment requires a few dependencies: (This list does not try to be exhaustive, but rather tries to provide a decent starting point. For detailed instructions check out the individual projects):

just
rust
libwayland
mesa (or third-party libEGL/libGL implementations, though interfacing with mesa's libglvnd is generally recommended).
libseat
libxkbcommon
libinput
udev
gtk4
dbus

optionally (though the build-system might currently require these libraries):

libsystemd
libpulse
pop-launcher

Testing

The easiest way to test Cosmic DE currently is by building a systemd system extension (see man systemd-sysext).

git clone --recurse-submodules https://github.com/pop-os/cosmic-epoch
cd cosmic-epoch
just sysext

This will create a system-extension called cosmic-sysext, that you can move (without renaming!) into e.g. /var/lib/extensions. After starting systemd-sysext.service (sudo systemctl enable --now systemd-sysext) and refreshing (sudo systemd-sysext refresh) or rebooting COSMIC will be an available option in your favorite display manager.

Note: An extension created this way will be linked against specific libraries on your system and will not work on other distributions. It also requires the previously mentioned libraries/dependencies at runtime to be installed in your system (the system extension does not carry these libraries).

It is thus no proper method for long term deployment.

Experimental X Support

With opam installed X support using wayland-proxy-virtwl can be optionally enabled during installation. When building, use just x=1 sysext and after refreshing with sudo systemd-sysext refresh, run

systemctl --user daemon-reload
systemctl --user enable --now wayland-proxy-virtwl

Packaging

Cosmic DE is packaged for Pop!_OS for reference look at the debian folders in the projects repositories. These and the justfile inside this repository may be used as references on how to package Cosmic DE, though no backwards-compatibility guarantees are provided at this stage.

Versioning

Cosmic DE is very much still work-in-progress and thus does not follow a versioning scheme so far. We do our best to keep the referenced submodule commits in this repository building and working together, as a consequence they might not contain the latest updates and features from these repositories (yet).

Notes on versioning and packaging all these components together properly will be added at a later stage once Cosmic DE gets its first release.