Warning: The install command is a part of the legacy v1 style of cabal usage. Please switch to using either the new project style and the new-install command or the legacy v1-install alias as new-style projects will become the default in the next version of cabal-install. Please file a bug if you cannot replicate a working v1- use case with the new-style commands. For more information, see: https://wiki.haskell.org/Cabal/NewBuild Resolving dependencies... Starting effect-stack-0.1.0.1 Building effect-stack-0.1.0.1 Failed to install effect-stack-0.1.0.1 Build log ( /home/builder/.cabal/logs/ghc-8.6.3/effect-stack-0.1.0.1-5IePJBTkvaM8MdY8xcN4Vc.log ): cabal: Entering directory '/tmp/cabal-tmp-25705/effect-stack-0.1.0.1' Configuring effect-stack-0.1.0.1... Preprocessing library for effect-stack-0.1.0.1.. Building library for effect-stack-0.1.0.1.. [1 of 8] Compiling Control.Monad.Stack.Accum ( Control/Monad/Stack/Accum.hs, dist/build/Control/Monad/Stack/Accum.o ) Control/Monad/Stack/Accum.hs:12:1: error: Could not find module ‘Control.Monad.Trans.RWS.CPS’ Perhaps you meant Control.Monad.Trans.RWS (from transformers-0.5.5.0) Control.Monad.Trans.RWS.Lazy (from transformers-0.5.5.0) Control.Monad.Trans.RWS.Strict (from transformers-0.5.5.0) Use -v to see a list of the files searched for. | 12 | import Control.Monad.Trans.RWS.CPS as RC | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Control/Monad/Stack/Accum.hs:19:1: error: Could not find module ‘Control.Monad.Trans.Writer.CPS’ Perhaps you meant Control.Monad.Trans.Writer (from transformers-0.5.5.0) Control.Monad.Trans.Writer.Lazy (from transformers-0.5.5.0) Control.Monad.Trans.Writer.Strict (from transformers-0.5.5.0) Use -v to see a list of the files searched for. | 19 | import Control.Monad.Trans.Writer.CPS as WC | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cabal: Leaving directory '/tmp/cabal-tmp-25705/effect-stack-0.1.0.1' cabal: Error: some packages failed to install: effect-stack-0.1.0.1-5IePJBTkvaM8MdY8xcN4Vc failed during the building phase. The exception was: ExitFailure 1