Containerised solutions

In addition to AppImage, it’s the other distribution agnostic universal packaging formats − Snaps and Flatpak − that hope to make things easier for users and developers.

The one main difference between Flatpak and Snap on the one hand, and AppImage on the other, is that the former run in sandboxed containers. Snaps use a modified AppArmor to isolate the apps, while Flatpak uses SELinux. Like AppImage, Snaps and Flatpak include all libraries and dependencies in the package itself. However, while Snaps can only use libraries included in its package, Flatpak can use libraries included in the package as well as shared libraries from another Flatpak.

There’s a lot of bickering from backers of both the camps extolling the technical virtues of their packaging format over the other. One point repeatedly raised by the Flatpak camp is that Snap was created in-house by Canonical and the technology is hard-coded to use the Snap package store. It’s also argued that while Flatpaks are more focused on delivering software to desktops, Snaps are basically just server technology that Canonical has adopted for the desktop.

A comparison of their technological virtues is almost meaningless since the furious pace of development of all these formats is rewriting their disadvantage over the competition. For example, you can now run AppImage apps inside containers created with Firejail. The process requires virtually no extra effort from the user, so long as they have Firejail installed. Recent versions of Firejail even guard against X display server attacks, like key-logging. In fact, proponents of AppImage argue that used together with Firejail AppImage apps are even more secure than Snap and Flatpak packages.