Resolving dependencies... Configuring mtl-2.2.1... Building mtl-2.2.1... Installed mtl-2.2.1 Configuring BNFC-2.8.1... Building BNFC-2.8.1... Installed BNFC-2.8.1 Downloading cubical-0.1.2... Configuring cubical-0.1.2... Failed to install cubical-0.1.2 Build log ( /home/builder/.cabal/logs/cubical-0.1.2.log ): cabal: Entering directory '/tmp/cabal-tmp-25543/cubical-0.1.2' [1 of 1] Compiling Main ( /tmp/cabal-tmp-25543/cubical-0.1.2/dist/setup/setup.hs, /tmp/cabal-tmp-25543/cubical-0.1.2/dist/setup/Main.o ) Linking /tmp/cabal-tmp-25543/cubical-0.1.2/dist/setup/setup ... /bin/sh: 1: bnfc: not found setup: bnfc command not found or error127 CallStack (from HasCallStack): error, called at /tmp/cabal-tmp-25543/cubical-0.1.2/dist/setup/setup.hs:22:26 in main:Main cabal: Leaving directory '/tmp/cabal-tmp-25543/cubical-0.1.2' cabal: Error: some packages failed to install: cubical-0.1.2 failed during the configure step. The exception was: ExitFailure 1