let

  rust_overlay = import (builtins.fetchTarball
    "https://github.com/oxalica/rust-overlay/archive/master.tar.gz");

  pkgs = import <nixpkgs> { overlays = [ rust_overlay ]; };

  rust_channel = pkgs.rust-bin.fromRustupToolchainFile ./nix/rust-toolchain;

  mqtt-explorer = pkgs.callPackage ./nix/mqtt-explorer.nix {} ;

  gmqtt = pkgs.python3Packages.buildPythonPackage rec {
      name = "gmqtt";
      version = "v0.6.10";
      src = pkgs.fetchFromGitHub {
            owner = "wialon" ;
            repo = "gmqtt";
            rev = "50bc08300d858c6e28d4975a989be578954bf7bd" ;
            sha256 = "1f51x3vkpkqa20mdqqakyk9ms7l5p3i4masrfhc6n7cr45qfr5fz";
      };

      buildInputs = [
      (pkgs.python3.withPackages(ps: [ 
          ps.codecov
          ps.pytest-asyncio
          ps.pytest
          ps.pytestcov
          ps.six
          ps.uvloop
            ]))
       ];

      propagatedBuildInputs = with pkgs.python3Packages; [ setproctitle ];

      meta = {
        homepage = "https://github.com/wialon/gmqtt";
        description = "gmqtt";
      };
    };

  miniconf = pkgs.python3Packages.buildPythonPackage rec {
        name = "miniconf";
        src = ./miniconf-mqtt;
        propagatedBuildInputs = with pkgs.python3Packages; [ gmqtt setuptools ];
    };

  stabilizer = pkgs.python3Packages.buildPythonPackage rec {
        name = "stabilizer" ;
        src = ./py;
        propagatedBuildInputs = with pkgs.python3Packages; [ setuptools ];  
    };

in
  pkgs.mkShell {
    buildInputs = [
      (pkgs.python3.withPackages(ps: [
        # List desired Python packages here.
        ps.numpy
        ps.setuptools
        ps.matplotlib
        gmqtt
        stabilizer
        miniconf

      ]))

      # List desired non-Python packages here
      # dfu ... for usb flashing
      pkgs.libtool
      rust_channel
      pkgs.pkg-config
      pkgs.libusb1
      pkgs.dfu-util
      pkgs.gcc-arm-embedded-8
      pkgs.stlink
      pkgs.mosquitto
      pkgs.gdb
      pkgs.automake
      pkgs.autoconf
      pkgs.texinfo
      pkgs.libftdi
      mqtt-explorer

    ];

    shellHook = ''
       export PATH="/home/$USER/.cargo/bin:$PATH" 
     '';

  }