Having outdated dependencies in `_oasis` files is also possible. In my case ocamlbuild wasn't the culprit of slow compilation times, I was living with oasis for some time and have experimented with it in other projects (e.g. `ctypes`), it was clearly the bottleneck (especially I guess in the dynamic mode).  As for Windows compatibility that's what was advertised to me in 2010 and the reason I supported it in my packages for some time but it seems to never have materialized. 

When you have a frank look at what oasis does for you and in how many loc and generated myocamlbuild.ml, it's easy too see that there is something wrong with the approach. I'd rather see people investing time in developing a good build system which offers support for packaging rather than trying to persist on that way. With opam and .install files the problem is *now* much simpler than people think it is, I solve it with a generic one hundred loc *trivial* shell script, that could be rewritten in OCaml for windows compatibility.