{
  description = "Vericert dependencies";

  inputs = { nixpkgs.url = "github:nixos/nixpkgs"; };

  outputs = { self, nixpkgs }:
    let vericertDevPackages = pkgs:
          let
            veriT' = pkgs.veriT.overrideAttrs (oA: {
              src = pkgs.fetchurl {
                url = "https://www.lri.fr/~keller/Documents-recherche/Smtcoq/veriT9f48a98.tar.gz";
                sha256 = "sha256-Pe46PxQVHWwWwx5Ei4Bl95A0otCiXZuUZ2nXuZPYnhY=";
              };
              meta.broken = false;
            });
            ncoq = pkgs.coq_8_17;
            ncoqPackages = pkgs.coqPackages_8_17;
          in
            pkgs.mkShell {
              buildInputs = with pkgs;
                [ ncoq ncoq.ocaml ncoqPackages.serapi dune_3 gcc python3 lp_solve veriT' zchaff ]
                ++ (with ncoq.ocamlPackages; [ findlib menhir menhirLib ocamlgraph ocp-indent utop merlin ])
                ++ (with python3Packages; [ alectryon sphinx_rtd_theme ]);
            };
    in {
      devShell.x86_64-linux = vericertDevPackages nixpkgs.legacyPackages.x86_64-linux;
      devShell.x86_64-darwin = vericertDevPackages nixpkgs.legacyPackages.x86_64-darwin;
    };
}