if [ -w . ]; then
        sandbox="$PWD"/.cabal-sandbox
        sandbox_config="$PWD"/cabal.sandbox.config
else
        sandbox="$HOME"/cabal-sandbox
        sandbox_config="$HOME"/cabal.sandbox.config
fi

source_dir="$(mktemp --tmpdir -d "cabal-helper.sdistXXXXXXXXX")"
build_dir="$(mktemp --tmpdir -d "cabal-helper.distXXXXXXXXX")"

NPROC=${NPROC:-1}