Dotfiles

These dotfiles are managed using Nix and Home Manager. Most config files are kept as plain text in modules/<application_name>/.

Installation

If you're reading this you'll probably want to take a look at the individual config files rather than setting up the entire dotfiles repo with Home Manager, but this can be done as follows:

git clone https://github.com/robbert-vdh/dotfiles.git ~/.dotfiles
~/.dotfiles/bin/update-dotfiles

PipeWire

If you want to use my PipeWire configuration, then you may want to be aware of the following:

1. Make sure you're using the very latest version of PipeWire and WirePlumber.

2. The two directories in the directory linked above should be copied to your ~/.config directory.

3. This configuration also uses regular realtime scheduling instead of rtkit, so make sure your user has realtime privileges.

4. If you're still using the stock PipeWire media session, then you'll need to disable that one first and enable WirePlumber:

   systemctl --user disable --now pipewire-media-session
   systemctl --user enable --now wireplumber

5. Some things you may want to change depending on your needs are:

   • The ALSA period size and the number of periods. You'll likely need to change this setting. PipeWire can run on very low ALSA period sizes and continuesly push small amounts of audio to the audio device while processing larger buffers in the graph. This greatly reduces the audio roundtrip latency, but the period size achievable with your hardware very much depends on your system. This value can be set in ~/.config/wireplumber/main.lua.d/90-alsa-config.lua, and the default is 64 frames/period with four periods. If you get any crackling, especially while also recording audio, then try changing these settings. Make sure to restart WirePlumber afterwards with systemctl --user restart wireplumber.
   • The sample rate. This is set to 48000 in my config. Change the sample rate values in both ~/.config/pipewire/pipewire.conf and ~/.config/wireplumber/main.lua.d/90-alsa-config.lua if you want to use a different sample rate.
   • The quantum size. This is PipeWire's virtual buffer size (which is different from the actual hardware period size used by the underlying ALSA backend), and it's always set to 512 samples in this configuration for a good tradeoff between low latency and headroom. If you want to change this, then change the three quantum size settings in ~/.config/pipewire/pipewire.conf or use pw-metadata -n settings 0 clock.force-quantum N to temporarily set the quantum size to N samples.

6. Finally, restart all PipeWire services for the configuration to take effect.

   systemctl --user restart pipewire pipewire-pulse wireplumber

7. (optional, but recommended)
   Enable the Pro Audio profile for your audio interface. You can do this in your desktop environment's volume manager (e.g. in KDE Plasma there's a dropdown menu next to the device's volume level) or in a standalone PulseAudio volume management GUI like pavucontrol-qt. This will expose all input and output channels on the device instead of acting like a normal desktop sound card.

8. (optional, but recommended)
   Configure PipeWire to always replace JACK. This is now done by default on Arch based distros with the pipewire-jack package and on Fedora with pipewire-jack-audio-connection-kit. On other distros you may need to set this up yourself.

Emacs

My Emacs configuration is based on Doom Emacs, which needs to be updated separately from the main Home Manager config. The files in modules/emacs/doom can simply be copied or symlinked to wherever Doom is installed.

Nix quirks

Nix, flakes, and Home Manager do 90% of the work well and the other 10% gets really messy. This is a (likely incomplete list) of the workarounds used in this Home Manager config for future reference:

• The bin/update-dotfiles script wraps around home-manager switch with a couple additional options:
  • Home Manager is told to specifically use this the flake from this repo's root so we don't need to symlink the home manager configuration to ~/.config/home-manager first.
  • The flake is run in impure mode so we can pass the path to this repo to the flake through the DOTFILES_DIR environment variable.
  • NIX_CONF_DIR is also overridden to point to the Nix config in this repo. This is needed for the nix cli to work so the nix cli can be enabled.
  • The script pulls changes from this repo and also makes sure that there are no untracked files in modules/. Those wouldn't be included in the flake which can be kind of confusing.
• Some config files, like Emacs', are symlinked to this repo using absolute paths, completely bypassing the Nix store. That is needed for them to be mutable, but Home Manager+flakes makes doing so incredibly difficult. That's why the aforementioned DOTFILES_DIR environment variable is needed, and why Home Manager needs to be ran in impure mode.
• modules/pacman/default.nix defines an activation script that symlinks some files to /etc. This is of course not something natively supported or encouraged by Home Manager, but it works.