Ocamlfind: Package `ptmap' not found

Hey guys, I am trying to build Haxe from the latest git commit. I have installed a bunch of opam dependencies that were missing but now I get:

ocamlfind: Package `ptmap' not found

And opam install ptmap gets me [ERROR] No package named ptmap found.. Any hint on how to install that dependency?

You may need to run opam update?

Silly me, that was it.