Developing in GNOME OS: systemd-sysext
In the old age, developing the desktop was simple™️. You only had to install a handful of toolchains, development headers, and tools from the distribution packages, run make install, execute say_prayer.sh and if you had not eaten meat on Friday you had a 25% chance for your system to work after a reboot.
Well, if you are an application developer Flatpak makes this very simple. Applications run against a containerized runtimes, with their own userspace. The only thing they need from the host system is a working Desktop Environment, Flatpak, and Portals. Builder and flatpak-builder along with all the integration we built into the Desktop make sure that it will be a breeze.