bug: Environment variables getting imported into dbus and systemd before River sets them

[Aerden]

Are you following the right branch?

• My Nixpkgs and Home Manager versions are in sync

Is there an existing issue for this?

• I have searched the existing issues

Issue description

River seems to run the init configuration file before WAYLAND_DISPLAY and DISPLAY are set, this causes the systemd integration of River to not work properly as these environment variables aren't set before it tries to run dbus-update-activation-environment --systemd.

I'm not exactly sure if this could be fixed from home-manager's side. I don't think River provides a way to execute commands after it has started outside of the init file.

Maintainer CC

No response

System information

- system: `"x86_64-linux"`
 - host os: `Linux 6.13.5-zen1, NixOS, 24.11 (Vicuna), 24.11.20250213.0b73e36`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Lix, like Nix) 2.91.1
System type: x86_64-linux
Additional system types: i686-linux, x86_64-v1-linux, x86_64-v2-linux, x86_64-v3-linux
Features: gc, signed-caches
System configuration file: /etc/nix/nix.conf
User configuration files: /home/aerden/.config/nix/nix.conf:/etc/xdg/nix/nix.conf:/home/aerden/.nix-profile/etc/xdg/nix/nix.conf:/nix/profile/etc/xdg/nix/nix.conf:/home/aerden/.local/state/nix/profile/etc/xdg/nix/nix.conf:/etc/profiles/per-user/aerden/etc/xdg/nix/nix.conf:/nix/var/nix/profiles/default/etc/xdg/nix/nix.conf:/run/current-system/sw/etc/xdg/nix/nix.conf
Store directory: /nix/store
State directory: /nix/var/nix
Data directory: /nix/store/zvj09ypbm7cgwkds1dpzb2lxwisb6vqb-lix-2.91.1/share`
 - nixpkgs: `/nix/store/h3g3hcnwm00lhr41fj9d9ahy002d6h7k-source`

[Aerden]

Upon further testing I managed to get dbus to import the variables by putting them in spawn. So it might be work putting systemdActivation inside a riverctl spawn command? I'm not sure why it won't work normally though.