configuration.nix

  environment.systemPackages = with pkgs; [
    (import vim.nix)
    [other packages]
];

vim.nix

with import <nixpkgs> {};

vim_configurable.customize {
        # Specifies the vim binary name.
        # E.g. set this to "my-vim" and you need to type "my-vim" to open this vim
        # This allows to have multiple vim packages installed (e.g. with a different set of plugins)
        name = "vim";
        vimrcConfig.customRC = ''
                set nu ai tabstop=4
        '';
        vimrcConfig.vam.knownPlugins = pkgs.vimPlugins;
        vimrcConfig.vam.pluginDictionaries = [
                { names = [
                        # Here you can place all your vim plugins
                        # They are installed managed by `vam` (a vim plugin manager)
                        "Syntastic"
                        "rust-vim"
                        "vim-racer"
                        "vim-addon-nix"
                ]; }
        ];
}