I hear that Racket is having some trouble determining "who broke what" in the package ecosystem. I do not know the specifics of this problem, but there was a recent discussion on the OCaml mailing list about OPAM's method of tracking package compatibility that may be relevant:
http://lists.ocaml.org/pipermail/opam-devel/2014-September/000654.html In particular, the second message (of 26) in the thread has a link to a survey paper on the formal aspects of package systems. http://www.dicosmo.org/Articles/2012-DiCosmoTreinenZacchiroli-Fmco.pdf
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