You're installing into a cabal sandbox and compiling directly with ghc (not cabal), but ghc doesn't know anything about the sandbox. You need to
Cheers Chris,
I have added your solution to the gist, for the future-me:
https://gist.github.com/adinapoli/d4c33a9d1ea85bcaebdf
A.
On Wednesday, 15 October 2014, Chris Wong
it to the package database with -package-db and tell it the package for linking with -package [2].
$ ghc -package-db .cabal-sandbox/x86_64-osx-ghc-7.8.3-packages.conf.d -package snappy HelloSnappy.hs Linking HelloSnappy ... $ ./HelloSnappy HelloSnappy: foo.jpg: openBinaryFile: does not exist (No such file or directory)
Alternatively, if you've got a recent version of cabal you can use
cabal exec -- ghc HelloSnappy.hs
instead.
You can also load up GHCi in the sandbox using `cabal exec ghci` or `cabal repl`.
Chris