-Build-Depends: debhelper (>> 4.0.0), ocaml-3.06, ocaml-findlib, libpcre-ocaml-dev-4.30.0, libocamlnet-ocaml-dev-0.94
+Build-Depends: debhelper (>> 4.0.0), ocaml-3.07, ocaml-findlib, libpcre-ocaml-dev (>= 4.30.0), libocamlnet-ocaml-dev (>= 0.94), graphviz