Dotfiles for i3-gaps and polybar for my Arch build.
These config files have some specific settings to my system, I don't think you would be pleased with the results if you copy directly. Rather, try to gather the essence of the files, if you want to replicate the visual effects.
For spotify in the polybar check out this repository. You need to change the path of the script to where you want to keep it. Currently it is set at ~/.config/polybar/scripts/spotify_status.py.