builder-dark.vim is a vim color scheme based on the builder-dark theme from Gnome Builder (which is itself based on freedesktop.org's Tango color palette).
This color scheme requires full color support in your terminal of
choice and the following to be set in your ~/.vimrc file:
set termguicolors
Copy colors/builder-dark.vim to ~/.vim/colors/ then add the following to your ~/.vimrc file:
colorscheme builder-dark