Customizing COSMIC: theming and applications

It's Back to School season, so grab yourself a brand new discounted computer and let's get back to COSMIC class! Our new, not yet released Rust-based desktop environment for Pop!_OS and other Linux distros is filling out with some essential systems that cater the DE to both users and developers alike. Customization is one of our main focuses for COSMIC, and was a huge focus for us in August, too.

There's a lot of cool stuff in this update about COSMIC. First and foremost, customisation is important, so they've effectively implemented something similar to Android's Material You theming engine, where the desktop environment will automatically determine derived colours that match the colour you've chosen as to maintain readability, contrast, and so on. You can also set the density of the interface, and how 'rounded' everything looks. Sadly, there's no word on actual theming in there, but they do mention that nothing in the components of the design system is meant to be hard-coded", so hopefully this means custom themes that radically alter the look of the UI are possible.

There's also a new API for application developers.

We added an application API to the libcosmic widget library to provide a framework for developing applications and applets in COSMIC DE. It automates integration with COSMIC theme support, along with Wayland protocols, COSMIC's configuration back-end, and common application elements like header bars and navigation. For application developers, this means convenient development without having to worry about managing the low-level desktop and window manager integrations. For us, this ensures consistency across COSMIC applications and applets.

COSMIC is shaping up nicely, and I can't wait to try it out.