diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e6fef3a..3b1e34c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -50,6 +50,8 @@ jobs:
         # For older GHCs
         brew install llvm@13 --quiet # Suppress deprecation warning
         echo /opt/homebrew/opt/llvm@13/bin >> $GITHUB_PATH
+        # https://gitlab.haskell.org/ghc/ghc/-/issues/20592#note_391266
+        echo "C_INCLUDE_PATH=`xcrun --show-sdk-path`/usr/include/ffi" >> "$GITHUB_ENV"
 
     - name: Build
       run: |
@@ -96,6 +98,16 @@ jobs:
         path: ~/.stack
         key: ${{ runner.os }}-${{ matrix.resolver }}-stack-key2
 
+    - name: Install dependencies (macOS)
+      if: runner.os == 'macOS'
+      run: |
+        brew update
+        # For older GHCs
+        brew install llvm@13 --quiet # Suppress deprecation warning
+        echo /opt/homebrew/opt/llvm@13/bin >> $GITHUB_PATH
+        # https://gitlab.haskell.org/ghc/ghc/-/issues/20592#note_391266
+        echo "C_INCLUDE_PATH=`xcrun --show-sdk-path`/usr/include/ffi" >> "$GITHUB_ENV"
+
     - name: Build
       run: |
         stack build $STACK_EXTRA_ARGS --test --bench --no-run-tests --no-run-benchmarks