Running Erlang's observer on Wayland


I am trying to run Erlang’s observer app under Wayland, and the only thing I get is: “Error: Unable to initialize GTK+, is DISPLAY set properly?”

If I set DISPLAY=:0 and start Xwayland then all works fine, but no luck running it without those two.

I use Erlang 23 and Elixir 1.11 under NixOS 21.05.

Has anyone ran into this?

I think we may need a NixOS expert here, but my hunch is that the libwxgtk / gtk library the erlang installation is using is compiled without Wayland support. meaning that you won’t get it running without Xwayland. Unfortunately I know very little of NixOS.

Hey Hubert

You may be right. Here’s the Erlang package definition nixpkgs/generic-builder.nix at master · NixOS/nixpkgs · GitHub but it mentions Wayland nowhere. I guess the linked GTK may be to blame.