Create an XDG DESKTOP PORTAL backend for regolith

Mentor: Soumya Ranjan Patnaik

Time Estimation 350 hours

Project Brief

XDG Desktop Portal or XDP is a service that provides applications with standardized interfaces to interact with the host system's desktop environment. It was originally designed for exposing functionality to flatpaks without sacrificing the security of the sandbox.

The portal interfaces are exposed to application via DBus, and are implemented by backends which are usually specific to the desktop environment. You can find examples and links to the source code for portal backends here

As of today, Regolith doesn't have a working xdg-desktop-portal backend. This means apps that rely on XDP may not work.

Your Job

Create a working xdg-desktop-portal backend for regolith.You can either create one from scratch, or fork one of the existing ones. You do not need to implement all the interfaces as xdg-desktop-portal-gtk already implements many of them.

You can also use the no-op backend provided by regolith, i.e. xdg-desktop-portal-regolith, as a starting point, which is a fork of xdg-desktop-portal-pantheon, which is the backend used by elementary OS.

Qualification tasks

  • Figure out the portals that are not available in xdg-desktop-portal-gtk or don't work as expected. DynamicLauncher, Documents, Permission Store and Location are some examples

  • Come up with a plan and prove that you can execute on it by doing its initial steps. Bonus points if you can get ANY one of the interfaces, which are currently unimplemented to work on regolith (it should work in xdp)


  • Official documenation for creating portal backends can be found here
  • There is an excellent talk by one of the maintainers of xdg-desktop-portal, which might be one of the best resources learn about understand portals, second only to the documenation Watch from 2:37:47 to 3:08:07.


  • You will have to implement GUI prompts for users to allow/deny permissions to access certain portals. You may also need to keep track of accepted and denied permissions
  • The portals backend should support the Wayland session as well as the X11
  • You can install the ASHPD demo application to test which interfaces work and which don't. You can also use it to test your custom XDP backend implementation session.