The configuration files I use across different setups for different applications.
$ git clone --recurse-submodules https://github.com/serd223/dotfiles.git
$ mv ./dotfiles ~/dotfiles
The contents of this repository must be placed at ~/dotfiles/ as most scripts/configs here assume so.
The install scripts copy your existing configs to ~/dotfiles/bak/ before changing your configs (bak is created if it doesn't exist).
Some files (notably tmux.conf) contain some platform-dependent configs but they should auto-detect the platform and do stuff according to that (.tmux.conf uses uname to detect the platform, for instance).
There is a Brewfile in the repository for my macos setup, it isn't referenced by install_macos.sh since it is only really useful for a brand new environment. It can be used with:
$ brew bundle --file=~/dotfiles/Brewfile