Is this buggy behavior? Installing yi... ... setup: alex version >=2.0.1 && <3 is required but it could not be found. cabal: Error: some packages failed to install: yi-0.3 failed during the configure step. The exception was: exit: ExitFailure 1 $ cabal install alex Resolving dependencies... Downloading alex-2.2... [1 of 1] Compiling Main ( Setup.lhs, dist/setup/Main.o ) ... I observed similar behavior with happs depending on happy. I had to issue an install command for happy and then happs-hsp-template installed. I would guess that what alex and happy have in common is that they are indirect (second order?) dependencies of the user's specified package. Pure speculation on my part. -- Darrin