{
  description = "ESP32 development tools";
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-25.11";
    flake-utils.url = "github:numtide/flake-utils";
    nixpkgs-esp-dev = {
      #url = "github:mirrexagon/nixpkgs-esp-dev";
      url = "github:dvdvgt/nixpkgs-esp-dev/update-v6.0.1";
      inputs = {
        nixpkgs.follows = "nixpkgs";
        flake-utils.follows = "flake-utils";
      };
    };
  };
  outputs =
    {
      self,
      nixpkgs,
      flake-utils,
      nixpkgs-esp-dev,
    }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        idfVersion = "v6.0.1";
        pkgs = import nixpkgs {
          inherit system;
          overlays = [ (import "${nixpkgs-esp-dev}/overlay.nix") ];
          config.permittedInsecurePackages = [
            "python3.13-ecdsa-0.19.1"
          ];
        };
        autoSerialPort = pkgs.writeShellScriptBin "esp-port" ''
          set -euo pipefail

          # Try common ESP USB serial patterns
          # TODO: reduce to Waveshare ESP32-S3 detection
          PORT=$(
            for p in /dev/serial/by-id/*; do
              case "$p" in
                *CP210*|*ch340*|*USB*|*ESP*) echo "$p"; break ;;
              esac
            done
          )

          if [ -z "$PORT" ]; then
            echo "No ESP serial device found in /dev/serial/by-id"
            echo "Fallback: listing /dev/ttyUSB* /dev/ttyACM*"
            ls /dev/ttyUSB* /dev/ttyACM* 2>/dev/null || true
            exit 1
          fi

          echo "$PORT"
        '';
        esp-idf = pkgs.esp-idf-full.override {
          rev = idfVersion;
          sha256 = "sha256-4KJa686qc+u7XkF/GS2o53l1SpwP2EmdqAn/qmlL1yU=";
        };
      in
      {
        apps = {
          run-agent = {
            type = "app";
            program = "${pkgs.writeShellScript "run-agent" ''
              podman run -it --rm -v ./:/src -v ./models.json:/root/.pi/agent/models.json --device=/dev/ttyACM0 pidev:latest
            ''}";
          };
          build-agent = {
            type = "app";
            program = "${pkgs.writeShellScript "build-agent" ''
              podman build -t pidev:latest -f Containerfile .
            ''}";
          };
          menuconfig = {
            type = "app";
            meta.description = "⚙️ Open ESP-IDF configuration menu (sdkconfig)";
            program = "${pkgs.writeShellScriptBin "idf-menuconfig" ''
              ${esp-idf}/tools/idf.py menuconfig
            ''}/bin/idf-menuconfig";
          };
          build = {
            type = "app";
            meta.description = "🧱 Build ESP32 firmware using ESP-IDF ${idfVersion}";
            program = "${pkgs.writeShellScriptBin "idf-build" ''
              ${esp-idf}/tools/idf.py build
            ''}/bin/idf-build";
          };
          flash = {
            type = "app";
            meta.description = "⚡ Flash firmware to ESP32-S3 over auto-detected serial port";
            program = "${pkgs.writeShellScriptBin "idf-flash" ''
              set -euo pipefail

              PORT=$(${autoSerialPort}/bin/esp-port)
              echo "Flashing on: $PORT"

              ${esp-idf}/tools/idf.py -p "$PORT" flash
            ''}/bin/idf-flash";
          };
          monitor = {
            type = "app";
            meta.description = "📡 Open serial monitor for ESP32 logs";
            program = "${pkgs.writeShellScriptBin "idf-monitor" ''
              set -euo pipefail

              PORT=$(${autoSerialPort}/bin/esp-port)
              echo "Monitoring: $PORT"

              ${esp-idf}/tools/idf.py -p "$PORT" monitor
            ''}/bin/idf-monitor";
          };
          clean = {
            type = "app";
            meta.description = "🧹 Clean ESP-IDF build directory";
            program = "${pkgs.writeShellScriptBin "idf-clean" ''
              ${esp-idf}/tools/idf.py clean
            ''}/bin/idf-clean";
          };
          full = {
            type = "app";
            meta.description = "🚀 Full pipeline: build → flash → monitor";
            program = "${pkgs.writeShellScriptBin "idf-full" ''
              set -euo pipefail

              PORT=$(${autoSerialPort}/bin/esp-port)

              echo "🧱 Building..."
              ${esp-idf}/tools/idf.py build
              echo "⚡ Flashing on $PORT..."
              ${esp-idf}/tools/idf.py -p "$PORT" flash
              echo "📡 Starting monitor..."
              ${esp-idf}/tools/idf.py -p "$PORT" monitor
            ''}/bin/idf-full";
          };
        };
        devShells.default = pkgs.mkShell {
          buildInputs = with pkgs; [
            esp-idf
            git
            minicom
            usbutils
            gawk
            coreutils
            cmake
            ninja
          ];
        };
      }
    );
}