Typical shell recipe

shell.nix

{ pkgs ? import <nixpkgs> { }, pythonPackages ? pkgs.python3Packages }:

let 
    pkgs = import (builtins.fetchTarball {
      url = "https://github.com/costrouc/nixpkgs/archive/46976eff15c48713f2aa99bdbafa8229cb031262.tar.gz";
      sha256 = "1q32jjv87n4dqchi00bj11bmy99pp72qdy3wy4c4fqxxchh63y38";
    }) { };

    pythonPackages = pkgs.python3Packages;
    
    myNumpy = pythonPackages.numpy.overrideAttrs(numpy.overrideAttrs (oldAttrs: {
      name = "${oldAttrs.pname}-master";

      buildInputs = oldAttrs.buildInputs ++ [ super.cython ];

      src =  builtins.fetchTarball {
        url = "https://github.com/numpy/numpy/archive/master.tar.gz";
      };
    });
in
pkgs.mkShell {
  buildInputs = with pythonPackages; [ pkgs.sqlite datasette pytest myNumpy ];

  shellHook = ''
    export SQLITE_TMPDIR=/tmp
  '';
}