anchor.diff: -{ stdenv, fetchurl, ocaml, findlib, ocamlbuild, opam }:
  +{ stdenv, fetchurl, ocaml, findlib, ocamlbuild, opaline }:
   
   let
     inherit (stdenv.lib) getVersion versionAtLeast;
  
positive.code:     sha256 = "0czj41sr8jsivl3z8wyblf9k971j3kx2wc3s0c1nhzcc8allg9i2";
    };
  
    buildInputs = [ ocaml findlib ocamlbuild opam ];
  
    createFindlibDestdir = true;
  
  
negative.code: 
    buildPhase = "ocaml pkg/build.ml native=true native-dynlink=true";
  
    installPhase = "opaline -libdir $OCAMLFIND_DESTDIR";
  
    meta = with stdenv.lib; {
      description = "Basic types for computer graphics in OCaml";
  