config.nix

{
    packageOverrides = pkgs: {
        pkgs.python37.pkgs.opencv4 = pkgs.python37.pkgs.opencv4.override { enableFfmpeg = true; };
    };
}

shell.nix

with import (builtins.fetchGit {
  name = "nixos-20-03-2020-06-09";
  url = "https://github.com/nixos/nixpkgs-channels/";
  ref = "refs/heads/nixos-20.03";
  rev = "70717a337f7ae4e486ba71a500367cad697e5f09";
}) { config = import ./config.nix; };

let
  py = pkgs.python37;
in
stdenv.mkDerivation rec {
  name = "python-environment";

  buildInputs = [
    py
    swig4
    cudatoolkit_10
    py.pkgs.opencv4
    py.pkgs.cython
    py.pkgs.tensorflowWithCuda
    py.pkgs.dill
    py.pkgs.fire
    py.pkgs.matplotlib
    py.pkgs.numba
    py.pkgs.psutil
    py.pkgs.requests
    py.pkgs.scikitimage
    py.pkgs.scipy
    py.pkgs.tqdm
    py.pkgs.flask
  ];
}