diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index a48d768..5e1ae43 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -49,7 +49,7 @@ jobs:
     strategy:
       matrix:
         os: [ macos-11, windows-latest, ubuntu-latest ]
-        arch: [ ['x86', 'x86_64', 'AMD64', 'x86_64' ] ] #[suffix, mac, windows, linux] arch names
+        arch: [ [ 'x86', 'x86_64', 'AMD64', 'x86_64' ] ] #[suffix, mac, windows, linux] arch names
         include:
           - os: ubuntu-latest
             arch: [ 'ARM', 'arm64', 'ARM64', 'aarch64' ]
@@ -70,6 +70,14 @@ jobs:
           wget https://pileof.rocks/openmp-13.0.0-darwin21-Release.tar.gz
           sudo tar fvxz openmp-*.tar.gz -C /
 
+      - name: Select LLVM 13
+        if: runner.os == 'macOS'
+        run: |
+          echo "CC=$(brew --prefix llvm)/bin/clang" >> $GITHUB_ENV
+          echo "CXX=$(brew --prefix llvm)/bin/clang" >> $GITHUB_ENV
+          echo "LDFLAGS=-L$(brew --prefix)/opt/llvm/lib -Wl,-rpath,$(brew --prefix)/opt/llvm/lib" >> &GITHUB_ENV
+          echo "MACOSX_DEPLOYMENT_TARGET=10.9"
+
       - name: Install QEMU
         # install QEMU if building for arm linux
         uses: docker/setup-qemu-action@v2
diff --git a/quicktex/util.h b/quicktex/util.h
index 1860b82..70315d4 100644
--- a/quicktex/util.h
+++ b/quicktex/util.h
@@ -39,8 +39,8 @@ namespace quicktex {
 // std::ranges::range is currently not usable by default in libc++
 template <class T>
 concept range = requires(T &t) {
-                    std::ranges::begin(t);
-                    std::ranges::end(t);
+                    std::begin(t);
+                    std::end(t);
                 };
 
 template <class T>