A couple of years ago I created some nix wallpapers using the gruvbox colorscheme:
Now with nix-wallpaper you can easily generate and customise similar wallpapers for yourself! nix-wallpaper is a flake containing a package which builds a wallpaper, and the color, resolution, aspect ratio, and logo size of these wallpapers can be customised by overriding that package (see the README for details).
nix-wallpaper also comes with some built-in colorschemes, including the gruvbox variants above.
Feedback welcome so long as it’s not complaints about how I chose to number the lambdas 
.