Resolving dependencies... Configuring mtl-2.2.1... Configuring network-2.6.3.1... Building mtl-2.2.1... Building network-2.6.3.1... Configuring syb-0.6... Installed mtl-2.2.1 Building syb-0.6... Configuring utf8-string-1.0.1.1... Installed syb-0.6 Building utf8-string-1.0.1.1... Configuring text-1.2.2.1... Installed network-2.6.3.1 Building text-1.2.2.1... Installed utf8-string-1.0.1.1 Configuring url-2.1.3... Building url-2.1.3... Installed url-2.1.3 Installed text-1.2.2.1 Configuring parsec-3.1.11... Building parsec-3.1.11... Installed parsec-3.1.11 Configuring network-uri-2.6.1.0... Configuring json-0.9.1... Building network-uri-2.6.1.0... Building json-0.9.1... Installed network-uri-2.6.1.0 Configuring HTTP-4000.3.3... Building HTTP-4000.3.3... Installed json-0.9.1 Installed HTTP-4000.3.3 Configuring gt-tools-0.1.4.2... Building gt-tools-0.1.4.2... Failed to install gt-tools-0.1.4.2 Build log ( /home/builder/.cabal/logs/gt-tools-0.1.4.2.log ): cabal: Entering directory '/tmp/cabal-tmp-22073/gt-tools-0.1.4.2' Configuring gt-tools-0.1.4.2... Building gt-tools-0.1.4.2... Preprocessing executable 'gtc' for gt-tools-0.1.4.2... [1 of 6] Compiling Gt.Langs ( Gt/Langs.hs, dist/build/gtc/gtc-tmp/Gt/Langs.o ) [2 of 6] Compiling Gt.Helpers ( Gt/Helpers.hs, dist/build/gtc/gtc-tmp/Gt/Helpers.o ) [3 of 6] Compiling Gt.Net ( Gt/Net.hs, dist/build/gtc/gtc-tmp/Gt/Net.o ) [4 of 6] Compiling Gt.Translation ( Gt/Translation.hs, dist/build/gtc/gtc-tmp/Gt/Translation.o ) [5 of 6] Compiling Gt.Core ( Gt/Core.hs, dist/build/gtc/gtc-tmp/Gt/Core.o ) [6 of 6] Compiling Main ( Gtc/gtc.hs, dist/build/gtc/gtc-tmp/Main.o ) Gtc/gtc.hs:14:1: error: Failed to load interface for ‘System.Environment.UTF8’ Perhaps you meant System.Environment (from base-4.9.0.0) Use -v to see a list of the files searched for. cabal: Leaving directory '/tmp/cabal-tmp-22073/gt-tools-0.1.4.2' cabal: Error: some packages failed to install: gt-tools-0.1.4.2 failed during the building phase. The exception was: ExitFailure 1