flake.nix.md
{
  description = "Nix flake";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    flake-parts.url = "github:hercules-ci/flake-parts";
    import-tree.url = "github:vic/import-tree";
    home-manager = {
      url = "github:nix-community/home-manager";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = inputs: inputs.flake-parts.lib.mkFlake {inherit inputs;} (inputs.import-tree ./modules);
}

This is your flake.nix, your entrypoint to the flake.

It imports all files in the modules directory as flake-parts modules using the import-tree function