{
  description = "m3ta's personal Nix repository - Custom packages, overlays, and modules";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    nixpkgs-master.url = "github:NixOS/nixpkgs/master";

    # opencode needs newer bun from master
    opencode = {
      url = "github:anomalyco/opencode/v1.2.17";
      inputs.nixpkgs.follows = "nixpkgs-master";
    };

    # openspec - spec-driven development for AI coding assistants
    openspec = {
      url = "github:Fission-AI/OpenSpec";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = {
    self,
    nixpkgs,
    ...
  } @ inputs: let
    # Supported systems
    systems = ["x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin"];

    # Helper function to generate an attrset for each of the systems
    forAllSystems = nixpkgs.lib.genAttrs systems;

    # Helper to create pkgs for a given system
    pkgsFor = system:
      import nixpkgs {
        inherit system;
        config.allowUnfree = true;
      };
  in {
    # Custom packages - accessible via 'nix build .#package-name'
    packages = forAllSystems (system: let
      pkgs = pkgsFor system;
    in
      import ./pkgs {inherit pkgs inputs;});

    # Overlays - can be imported in your system configuration
    overlays = {
      # Default overlay: adds all custom packages
      default = final: prev:
        import ./pkgs {
          pkgs = final;
          inputs = inputs;
        };

      # Individual overlays for more granular control
      additions = final: prev:
        import ./pkgs {
          pkgs = final;
          inputs = inputs;
        };

      modifications = final: prev: import ./overlays/mods {inherit prev;};
    };

    # NixOS modules - for system-level configuration
    nixosModules = {
      default = ./modules/nixos;
      # Individual modules for selective imports
      ports = ./modules/nixos/ports.nix;
      mem0 = ./modules/nixos/mem0.nix;
    };

    # Home Manager modules - for user-level configuration
    homeManagerModules = {
      default = import ./modules/home-manager;
      ports = import ./modules/home-manager/ports.nix;
      zellij-ps = import ./modules/home-manager/zellij-ps.nix;
    };

    # Library functions - helper utilities for your configuration
    lib = forAllSystems (system: let
      pkgs = pkgsFor system;
    in
      import ./lib {lib = pkgs.lib;});

    # Development shells for various programming environments
    # Usage: nix develop .#<shell-name>
    # Available shells: default, python, devops, opencode
    devShells = forAllSystems (system: let
      pkgs = pkgsFor system;
    in
      import ./shells {inherit pkgs inputs;});

    # Formatter for 'nix fmt'
    formatter = forAllSystems (system: (pkgsFor system).alejandra);

    # Checks for 'nix flake check' - verifies all packages build
    checks = forAllSystems (system: let
      pkgs = pkgsFor system;
      packages = import ./pkgs {inherit pkgs inputs;};
    in
      builtins.mapAttrs (name: pkg: pkgs.lib.hydraJob pkg) packages
      // {
        formatting = pkgs.runCommand "check-formatting" {} ''
          ${pkgs.alejandra}/bin/alejandra --check ${./.}
          touch $out
        '';
      });

    # Templates for creating new packages/modules
    templates = {
      package = {
        path = ./templates/package;
        description = "Template for a new package";
      };
      nixos-module = {
        path = ./templates/nixos-module;
        description = "Template for a new NixOS module";
      };
      home-manager-module = {
        path = ./templates/home-manager-module;
        description = "Template for a new Home Manager module";
      };
    };
  };
}