Resolving dependencies... Starting cereal-0.5.8.1 Starting splitmix-0.1.0.3 Starting colour-2.3.6 Starting directory-1.3.6.2 Building cereal-0.5.8.1 Building splitmix-0.1.0.3 Building colour-2.3.6 Building directory-1.3.6.2 Completed splitmix-0.1.0.3 Starting text-1.2.5.0 Building text-1.2.5.0 Completed directory-1.3.6.2 Starting transformers-compat-0.7 Building transformers-compat-0.7 Completed cereal-0.5.8.1 Starting unliftio-core-0.2.0.1 Completed colour-2.3.6 Starting random-1.2.0 Building unliftio-core-0.2.0.1 Building random-1.2.0 Completed unliftio-core-0.2.0.1 Starting process-1.6.13.2 Completed transformers-compat-0.7 Starting ansi-terminal-0.11 Building ansi-terminal-0.11 Building process-1.6.13.2 Completed random-1.2.0 Starting QuickCheck-2.14.2 Completed ansi-terminal-0.11 Starting ansi-wl-pprint-0.6.9 Building QuickCheck-2.14.2 Building ansi-wl-pprint-0.6.9 Completed process-1.6.13.2 Completed ansi-wl-pprint-0.6.9 Starting optparse-applicative-0.16.1.0 Building optparse-applicative-0.16.1.0 Completed text-1.2.5.0 Starting hashable-1.3.2.0 Building hashable-1.3.2.0 Completed optparse-applicative-0.16.1.0 Completed hashable-1.3.2.0 Starting async-2.2.3 Building async-2.2.3 Completed async-2.2.3 Starting unliftio-0.2.19 Building unliftio-0.2.19 Completed QuickCheck-2.14.2 Completed unliftio-0.2.19 Starting ticket-management-0.2.0.0 Building ticket-management-0.2.0.0 Failed to install ticket-management-0.2.0.0 Build log ( /home/builder/.cabal/logs/ghc-8.10.2/ticket-management-0.2.0.0-7P9p35jAW8u8p43HRuBQCj.log ): cabal: Entering directory '/tmp/cabal-tmp-11601/ticket-management-0.2.0.0' Configuring ticket-management-0.2.0.0... Preprocessing library for ticket-management-0.2.0.0.. Building library for ticket-management-0.2.0.0.. [1 of 3] Compiling Imports ( src/Imports.hs, dist/build/Imports.o, dist/build/Imports.dyn_o ) [2 of 3] Compiling Data.Ticket ( src/Data/Ticket.hs, dist/build/Data/Ticket.o, dist/build/Data/Ticket.dyn_o ) src/Data/Ticket.hs:124:41: error: Not in scope: Set.alterF Perhaps you meant one of these: Set.filter (imported from Data.Set), Map.alterF (imported from Data.Map) Module Data.Set does not export alterF. | 124 | go' = maybe errMsg (fmap Just . Set.alterF go'' ticketID') | ^^^^^^^^^^ cabal: Leaving directory '/tmp/cabal-tmp-11601/ticket-management-0.2.0.0' cabal: Error: some packages failed to install: ticket-management-0.2.0.0-7P9p35jAW8u8p43HRuBQCj failed during the building phase. The exception was: ExitFailure 1