Hello, Is there a way to have certain files, with particular suffixes, treated as .ml/.mli respectively with ocamlbuild? I understand that ocaml compiler itself supports -intf/-impl/-intf-suffix, but it's not clear that ocamlbuild will allow use of these. Specifically, here is how all of the ocamlc/ocamldep/* suite of commands should be effected by the file extension: */*.xyz ocamlc/ocamldep -pp convertXyzProgram -impl theFile.xyz -intf-suffix xyzi */*.xyzi ocamlc/ocamldep -pp convertXyzProgram -intf theFile.xyzi Is there a way to do this with _tags or possibly resorting to a myocamlbuild.ml? I would be satisfied with a myocamlbuild rule that *moves* the .xyz to a .ml, but in that case errors are reported in terms of the generated .ml and not the original .xyz, which is unfortunate. I know the ocaml compler supports this, but does ocamlbuild? Jordan