Resolving dependencies... Configuring type-equality-0.1.0.1... Building type-equality-0.1.0.1... Failed to install type-equality-0.1.0.1 Build log ( /home/builder/.cabal/logs/type-equality-0.1.0.1.log ): cabal: Entering directory '/tmp/cabal-tmp-23625/type-equality-0.1.0.1' Warning: type-equality.cabal: Unknown fields: build-depends (line 21) Fields allowed in this section: name, version, cabal-version, build-type, license, license-file, license-files, copyright, maintainer, stability, homepage, package-url, bug-reports, synopsis, description, category, author, tested-with, data-files, data-dir, extra-source-files, extra-tmp-files, extra-doc-files Configuring type-equality-0.1.0.1... Building type-equality-0.1.0.1... Preprocessing library type-equality-0.1.0.1... [1 of 1] Compiling Data.Type.Equality ( src/Data/Type/Equality.hs, dist/build/Data/Type/Equality.o ) src/Data/Type/Equality.hs:35:1: error: Failed to load interface for ‘Prelude’ It is a member of the hidden package ‘base-4.9.0.0’. Perhaps you need to add ‘base’ to the build-depends in your .cabal file. Use -v to see a list of the files searched for. src/Data/Type/Equality.hs:38:1: error: Failed to load interface for ‘Control.Category’ It is a member of the hidden package ‘base-4.9.0.0’. Perhaps you need to add ‘base’ to the build-depends in your .cabal file. Use -v to see a list of the files searched for. cabal: Leaving directory '/tmp/cabal-tmp-23625/type-equality-0.1.0.1' cabal: Error: some packages failed to install: type-equality-0.1.0.1 failed during the building phase. The exception was: ExitFailure 1