I've installed stack on Windows 7 64 bits. When I do "stack build" I get the output below. It looks like a character encoding problem. The generated executable is okay. This problems exists with all projects. Stack uses ghc version 8.4.3? Kees d:\haskell\Sudoku>stack build [0mSudoku-0.1.0.0: unregistering (local file changes: src\CalcSudoku.hs)[0m [0mSudoku-0.1.0.0: build (lib + exe)[0m [0mPreprocessing library for Sudoku-0.1.0.0..[0m [0mBuilding library for Sudoku-0.1.0.0..[0m [0m[2 of 3] Compiling SudokuTypes ( src\SudokuTypes.hs, .stack-work\dist\7 d103d30\build\SudokuTypes.o )[0m [0m[3 of 3] Compiling CalcSudoku ( src\CalcSudoku.hs, .stack-work\dist\7d 103d30\build\CalcSudoku.o )[0m [0m[0m [0m[;1msrc\CalcSudoku.hs:181:1: [;1m[31merror:[0m[0m[;1m[0m[0m[;1m[0m [0m parse error (possibly incorrect indentation or mismatched brackets)[0m [0m[0m [0m[;1m[34m |[0m[0m[0m [0m[;1m[34m181 |[0m[0m [;1m[31mg[0m[0metMin :: [a] -> [a -> Int] -> a [0m[;1m[34m |[0m[0m[;1m[31m ^[0m[0m[0m [0m[0m[0m[0m[0m