[This message is more appropriate for a hackage mailing list I presume, but that doesn't seem to exist. Let me know if there's a better place to send it.] I'm having a hackage compile failure for a newly uplodaded package that has a QuickCheck 2.5 dependence. The error message is: [13 of 13] Compiling Test.QuickCheck.All ( Test/QuickCheck/All.hs, dist/build/Test/QuickCheck/All.o ) Test/QuickCheck/All.hs:15:1: Bad interface file: /usr/local/tmp/archive/install/lib/template-haskell-2.6.0.0/ghc-7.4.1/Language/Haskell/TH.hi Something is amiss; requested module template-haskell-2.6.0.0:Language.Haskell.TH differs from name found in the interface file template-haskell:Language.Haskell.TH The full log file is at (search for "Something is a miss" in it): http://hackage.haskell.org/packages/archive/sbv/2.2/logs/failure/ghc-7.4 Needless to say, I don't see this problem when I compile this package at home with the same compiler (ghc 7.4.1) as hackage is using; also Hackage has a successfully compiled QuickCheck 2.5 package. Could it be something related to the particular cabal/ghc installation on the hackage server? In particular, I don't understand why it picks template-haskell 2.6.0.0 when there's a newer version (2.7.0.0). As far as I can see, QuickCheck doesn't put an upper limit on its template haskell version dependency. I'd appreciate any pointers with this. (Googling and questions on the #haskell irc channel didn't help much, unfortunately.) -Levent.