Resolving dependencies... Configuring primitive-0.6.1.0... Configuring network-2.6.3.1... Building primitive-0.6.1.0... Building network-2.6.3.1... Installed primitive-0.6.1.0 Configuring vector-0.11.0.0... Building vector-0.11.0.0... Installed network-2.6.3.1 Configuring splice-0.6.1.1... Building splice-0.6.1.1... Installed splice-0.6.1.1 Installed vector-0.11.0.0 Configuring PortFusion-1.0.3... Building PortFusion-1.0.3... Failed to install PortFusion-1.0.3 Build log ( /home/builder/.cabal/logs/PortFusion-1.0.3.log ): cabal: Entering directory '/tmp/cabal-tmp-32213/PortFusion-1.0.3' Configuring PortFusion-1.0.3... Building PortFusion-1.0.3... Preprocessing executable 'PortFusion' for PortFusion-1.0.3... [1 of 1] Compiling Main ( src/Main.hs, dist/build/PortFusion/PortFusion-tmp/Main.o ) src/Main.hs:177:10: error: Duplicate instance declarations: instance Read Port -- Defined at src/Main.hs:177:10 instance Read PortNumber -- Defined in ‘network-2.6.3.1:Network.Socket.Types’ cabal: Leaving directory '/tmp/cabal-tmp-32213/PortFusion-1.0.3' cabal: Error: some packages failed to install: PortFusion-1.0.3 failed during the building phase. The exception was: ExitFailure 1