diff --git a/.github/workflows/haskell.yml b/.github/workflows/haskell.yml
index 8108500..fd8412d 100644
--- a/.github/workflows/haskell.yml
+++ b/.github/workflows/haskell.yml
@@ -35,7 +35,7 @@ jobs:
         cabal: ["3.2"]
         ghc: ["8.6.5", "8.8.3", "8.10.1"]
     env:
-      CONFIG: "--enable-tests --enable-benchmarks --disable-optimizations -j"
+      CONFIG: "--enable-tests --enable-benchmarks "
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-haskell@v1.1.2
@@ -69,7 +69,7 @@ jobs:
           key: ${{ runner.os }}-${{ matrix.ghc }}-${{ hashFiles('cabal.project.freeze') }}
           restore-keys: |
             ${{ runner.os }}-${{ matrix.ghc }}-
-      - run: cabal v2-build $CONFIG
-      - run: cabal v2-test $CONFIG
-      - run: cabal v2-haddock $CONFIG
+      - run: cabal v2-build --disable-optimizations -j $CONFIG
+      - run: cabal v2-test --disable-optimizations -j $CONFIG
+      - run: cabal v2-haddock -j $CONFIG
       - run: cabal v2-sdist