This is my prototype  to learn emacs and apply the NixOS module system abstraction model to do something interesting.
Currently you can already enable some popular modes like org and evil and it will get what is missing and show warnings if there is some concern.
Interestingly, the abstraction model allows to do something that I call trait, for example: if
evil-mode are both enabled you can implicitly enable
Currently I am customizing it for my needs, the module model allows me to create modules to use locally in my personal dotfiles and then “upstream” them to the main repo.
 GitHub - lucasew/nix-emacs: Use the same module system that leverages NixOS to configure your emacs customization
Is it similar to the emacs-init home-manager module?
Whoa, this thing seems to have pretty advanced stuff.
This project is a wrapper generator, no coupling with home-manager or NixOS, the init.el is generated on build time with the dependencies, after built is just start using it.
I’ve made modules mostly for higher-level stuff BTW.