core.nix

  nixpkgs.config = {
    sqlite.interactive = true;
    packageOverrides = (import ./overrides.nix).packageOverrides;
  };

overrides.nix

{ 
  packageOverrides = pkgs: rec {
    openiscsi = pkgs.callPackage ./open-iscsi.nix {};
    toxvpn = pkgs.callPackage ./toxvpn.nix {};
    util = pkgs.callPackage ./util.nix {};
    chromefix = pkgs.callPackage ./chrome-fix.nix {};
    #nix = pkgs.stdenv.lib.overrideDerivation pkgs.nix (oldAttrs: {
    #  patches = [ ./status.patch ];
    #});
    linux_rpi_41 = let
      rev = "9e8e5dc45d7d4cafdfd38e0e809f873e78bbc8e9";
    in
    import <nixpkgs/pkgs/os-specific/linux/kernel/generic.nix> ( rec {
      inherit (pkgs) stdenv perl buildLinux;
      version = "4.1.10-${rev}";
      modDirVersion = "4.1.10";
      src = pkgs.fetchurl {
        url = "https://api.github.com/repos/raspberrypi/linux/tarball/${rev}";
        name = "linux-raspberrypi-${version}.tar.gz";
        sha256 = "1kjr15x54xs06ip7z3kcvbiylcs8pcp4dccd4jwywiyrnyl0i0qv";
      };
    });
    linuxPackages_rpi41 = pkgs.linuxPackagesFor linux_rpi_41 pkgs.linuxPackages_rpi;
    raspberrypifw = pkgs.callPackage ./raspberrypifw.nix {};
    rpPPPoE = pkgs.stdenv.lib.overrideDerivation pkgs.rpPPPoE (oldAttrs: {
      postInstall = ''
        echo noauth > $out/etc/ppp/pppoe-server-options
        echo lcp-echo-interval 10 >> $out/etc/ppp/pppoe-server-options
        echo lcp-echo-failure 2 >> $out/etc/ppp/pppoe-server-options
      '';
    });
  };
}