diff --git a/.github/actions/disk-space/action.yml b/.github/actions/disk-space/action.yml
index 8470ff68d..969cbf2cc 100644
--- a/.github/actions/disk-space/action.yml
+++ b/.github/actions/disk-space/action.yml
@@ -1,12 +1,12 @@
-name: 'Maximize build disk space'
-description: 'Maximize build disk space'
+name: 'Maximize build disk space for macOS'
+description: 'Maximize build disk space on macOS'
 inputs:
   root-reserve-mb:
     description: 'Space to be left free on the root filesystem, in Megabytes.'
     required: false
     default: '1024'
   temp-reserve-mb:
-    description: 'Space to be left free on the temp filesystem (/mnt), in Megabytes.'
+    description: 'Space to be left free on the temp filesystem (/private/tmp), in Megabytes.'
     required: false
     default: '100'
   swap-size-mb:
@@ -15,9 +15,7 @@ inputs:
     default: '4096'
   overprovision-lvm:
     description: |
-      Create the LVM disk images as sparse files, making the space required for the LVM image files *appear* unused on the
-      hosting volumes until actually allocated. Use with care, this can lead to surprising out-of-disk-space situations.
-      You should prefer adjusting root-reserve-mb/temp-reserve-mb over using this option.
+      (macOS does not support LVM in the same way as Linux, so this option is not applicable.)
     required: false
     default: 'false'
   build-mount-path:
@@ -26,15 +24,15 @@ inputs:
   build-mount-path-ownership:
     description: 'Ownership of the mount point path, defaults to standard "runner" user and group.'
     required: false
-    default: 'runner:runner'
+    default: 'runner:staff'
   pv-loop-path:
-    description: 'Absolute file path for the LVM image created on the root filesystem, the default is usually fine.'
+    description: 'Absolute file path for the disk image created on the root filesystem.'
     required: false
     default: '/pv.img'
   tmp-pv-loop-path:
-    description: 'Absolute file path for the LVM image created on the temp filesystem, the default is usually fine. Must reside on /mnt'
+    description: 'Absolute file path for the disk image created on the temp filesystem.'
     required: false
-    default: '/mnt/tmp-pv.img'
+    default: '/private/tmp/tmp-pv.img'
   remove-dotnet:
     description: 'Removes .NET runtime and libraries. (frees ~17 GB)'
     required: false
@@ -61,135 +59,125 @@ runs:
     - name: Disk space report before modification
       shell: bash
       run: |
+        echo "Memory and swap:"
+        vm_stat
+        echo
+
         echo "Available storage:"
-        sudo df -h
+        df -h
         echo
 
     - name: Maximize build disk space
       shell: bash
       run: |
-          set -euo pipefail
-
-          BUILD_MOUNT_PATH="${{ inputs.build-mount-path }}"
-          if [[ -z "${BUILD_MOUNT_PATH}" ]]; then
-            BUILD_MOUNT_PATH="${GITHUB_WORKSPACE}"
-          fi
-
-          echo "Arguments:"
-          echo
-          echo "  Root reserve:      ${{ inputs.root-reserve-mb }} MiB"
-          echo "  Temp reserve:      ${{ inputs.temp-reserve-mb }} MiB"
-          echo "  Swap space:        ${{ inputs.swap-size-mb }} MiB"
-          echo "  Overprovision LVM: ${{ inputs.overprovision-lvm }}"
-          echo "  Mount path:        ${BUILD_MOUNT_PATH}"
-          echo "  Root PV loop path: ${{ inputs.pv-loop-path }}"
-          echo "  Temp PV loop path: ${{ inputs.tmp-pv-loop-path }}"
-          echo -n "  Removing:     "
-          if [[ ${{ inputs.remove-dotnet }} == 'true' ]]; then
-            echo -n "dotnet "
-          fi
-          if [[ ${{ inputs.remove-android }} == 'true' ]]; then
-            echo -n "android "
-          fi
-          if [[ ${{ inputs.remove-haskell }} == 'true' ]]; then
-            echo -n "haskell "
-          fi
-          if [[ ${{ inputs.remove-codeql }} == 'true' ]]; then
-            echo -n "codeql "
-          fi
-          if [[ ${{ inputs.remove-docker-images }} == 'true' ]]; then
-            echo -n "docker "
-          fi
-          echo
-
-          # store owner of $GITHUB_WORKSPACE in case the action deletes it
-          WORKSPACE_OWNER="$(stat -c '%U:%G' "${GITHUB_WORKSPACE}")"
-
-          # ensure mount path exists before the action
-          sudo mkdir -p "${BUILD_MOUNT_PATH}"
-          sudo find "${BUILD_MOUNT_PATH}" -maxdepth 0 ! -empty -exec echo 'WARNING: directory [{}] is not empty, data loss might occur. Content:' \; -exec ls -al "{}" \;
-
-          echo "Removing unwanted software... "
-          if [[ ${{ inputs.remove-dotnet }} == 'true' ]]; then
-            sudo rm -rf /usr/share/dotnet
-          fi
-          if [[ ${{ inputs.remove-android }} == 'true' ]]; then
-            sudo rm -rf /usr/local/lib/android
-          fi
-          if [[ ${{ inputs.remove-haskell }} == 'true' ]]; then
-            sudo rm -rf /opt/ghc
-          fi
-          if [[ ${{ inputs.remove-codeql }} == 'true' ]]; then
-            sudo rm -rf /opt/hostedtoolcache/CodeQL
-          fi
-          if [[ ${{ inputs.remove-docker-images }} == 'true' ]]; then
-            sudo docker image prune --all --force
-          fi
-          echo "... done"
-
-          VG_NAME=buildvg
-
-          # github runners have an active swap file in /mnt/swapfile
-          # we want to reuse the temp disk, so first unmount swap and clean the temp disk
-          echo "Unmounting and removing swap file."
-          sudo swapoff -a
-          sudo rm -f /mnt/swapfile
-
-          echo "Creating LVM Volume."
-          echo "  Creating LVM PV on root fs."
-          # create loop pv image on root fs
-          ROOT_RESERVE_KB=$(expr ${{ inputs.root-reserve-mb }} \* 1024)
-          ROOT_FREE_KB=$(df --block-size=1024 --output=avail / | tail -1)
-          ROOT_LVM_SIZE_KB=$(expr $ROOT_FREE_KB - $ROOT_RESERVE_KB)
-          ROOT_LVM_SIZE_BYTES=$(expr $ROOT_LVM_SIZE_KB \* 1024)
-          sudo touch "${{ inputs.pv-loop-path }}" && sudo fallocate -z -l "${ROOT_LVM_SIZE_BYTES}" "${{ inputs.pv-loop-path }}"
-          export ROOT_LOOP_DEV=$(sudo losetup --find --show "${{ inputs.pv-loop-path }}")
-          sudo pvcreate -f "${ROOT_LOOP_DEV}"
-
-          # create pv on temp disk
-          echo "  Creating LVM PV on temp fs."
-          TMP_RESERVE_KB=$(expr ${{ inputs.temp-reserve-mb }} \* 1024)
-          TMP_FREE_KB=$(df --block-size=1024 --output=avail /mnt | tail -1)
-          TMP_LVM_SIZE_KB=$(expr $TMP_FREE_KB - $TMP_RESERVE_KB)
-          TMP_LVM_SIZE_BYTES=$(expr $TMP_LVM_SIZE_KB \* 1024)
-          sudo touch "${{ inputs.tmp-pv-loop-path }}" && sudo fallocate -z -l "${TMP_LVM_SIZE_BYTES}" "${{ inputs.tmp-pv-loop-path }}"
-          export TMP_LOOP_DEV=$(sudo losetup --find --show "${{ inputs.tmp-pv-loop-path }}")
-          sudo pvcreate -f "${TMP_LOOP_DEV}"
-
-          # create volume group from these pvs
-          sudo vgcreate "${VG_NAME}" "${TMP_LOOP_DEV}" "${ROOT_LOOP_DEV}"
-
-          echo "Recreating swap"
-          # create and activate swap
-          sudo lvcreate -L "${{ inputs.swap-size-mb }}M" -n swap "${VG_NAME}"
-          sudo mkswap "/dev/mapper/${VG_NAME}-swap"
-          sudo swapon "/dev/mapper/${VG_NAME}-swap"
-
-          echo "Creating build volume"
-          # create and mount build volume
-          sudo lvcreate -l 100%FREE -n buildlv "${VG_NAME}"
-          if [[ ${{ inputs.overprovision-lvm }} == 'true' ]]; then
-            sudo mkfs.ext4 -m0 "/dev/mapper/${VG_NAME}-buildlv"
-          else
-            sudo mkfs.ext4 -Enodiscard -m0 "/dev/mapper/${VG_NAME}-buildlv"
-          fi
-          sudo mount "/dev/mapper/${VG_NAME}-buildlv" "${BUILD_MOUNT_PATH}"
-          sudo chown -R "${{ inputs.build-mount-path-ownership }}" "${BUILD_MOUNT_PATH}"
-
-          # if build mount path is a parent of $GITHUB_WORKSPACE, and has been deleted, recreate it
-          if [[ ! -d "${GITHUB_WORKSPACE}" ]]; then
-            sudo mkdir -p "${GITHUB_WORKSPACE}"
-            sudo chown -R "${WORKSPACE_OWNER}" "${GITHUB_WORKSPACE}"
-          fi
+        set -euo pipefail
+
+        BUILD_MOUNT_PATH="${{ inputs.build-mount-path }}"
+        if [[ -z "${BUILD_MOUNT_PATH}" ]]; then
+          BUILD_MOUNT_PATH="${GITHUB_WORKSPACE}"
+        fi
+
+        echo "Arguments:"
+        echo
+        echo "  Root reserve:      ${{ inputs.root-reserve-mb }} MiB"
+        echo "  Temp reserve:      ${{ inputs.temp-reserve-mb }} MiB"
+        echo "  Swap space:        ${{ inputs.swap-size-mb }} MiB"
+        echo "  Overprovision LVM: ${{ inputs.overprovision-lvm }} (Not applicable on macOS)"
+        echo "  Mount path:        ${BUILD_MOUNT_PATH}"
+        echo "  Root PV loop path: ${{ inputs.pv-loop-path }}"
+        echo "  Temp PV loop path: ${{ inputs.tmp-pv-loop-path }}"
+        echo -n "  Removing:     "
+        if [[ ${{ inputs.remove-dotnet }} == 'true' ]]; then
+          echo -n "dotnet "
+        fi
+        if [[ ${{ inputs.remove-android }} == 'true' ]]; then
+          echo -n "android "
+        fi
+        if [[ ${{ inputs.remove-haskell }} == 'true' ]]; then
+          echo -n "haskell "
+        fi
+        if [[ ${{ inputs.remove-codeql }} == 'true' ]]; then
+          echo -n "codeql "
+        fi
+        if [[ ${{ inputs.remove-docker-images }} == 'true' ]]; then
+          echo -n "docker "
+        fi
+        echo
+
+        # store owner of $GITHUB_WORKSPACE in case the action deletes it
+        WORKSPACE_OWNER="$(stat -f '%Su:%Sg' "${GITHUB_WORKSPACE}")"
+
+        echo "Removing unwanted software... "
+        if [[ ${{ inputs.remove-dotnet }} == 'true' ]]; then
+          sudo rm -rf /usr/local/share/dotnet
+        fi
+        if [[ ${{ inputs.remove-android }} == 'true' ]]; then
+          sudo rm -rf /usr/local/lib/android
+        fi
+        if [[ ${{ inputs.remove-haskell }} == 'true' ]]; then
+          sudo rm -rf /usr/local/ghc
+        fi
+        if [[ ${{ inputs.remove-codeql }} == 'true' ]]; then
+          sudo rm -rf /usr/local/hostedtoolcache/CodeQL
+        fi
+        if [[ ${{ inputs.remove-docker-images }} == 'true' ]]; then
+          docker image prune --all --force
+        fi
+        echo "... done"
+
+        # No LVM on macOS, use disk images instead
+        VG_NAME=buildvg
+
+        echo "Creating disk images."
+        # Create a disk image for the root filesystem
+        ROOT_RESERVE_KB=$(expr ${{ inputs.root-reserve-mb }} \* 1024)
+        ROOT_FREE_KB=$(df -k / | tail -1 | awk '{print $4}')
+        ROOT_LVM_SIZE_KB=$(expr $ROOT_FREE_KB - $ROOT_RESERVE_KB)
+        hdiutil create -size ${ROOT_LVM_SIZE_KB}k -fs HFS+ -volname "${VG_NAME}-root" "${{ inputs.pv-loop-path }}"
+
+        # Create a disk image for the temp filesystem
+        TMP_RESERVE_KB=$(expr ${{ inputs.temp-reserve-mb }} \* 1024)
+        TMP_FREE_KB=$(df -k /private/tmp | tail -1 | awk '{print $4}')
+        TMP_LVM_SIZE_KB=$(expr $TMP_FREE_KB - $TMP_RESERVE_KB)
+        hdiutil create -size ${TMP_LVM_SIZE_KB}k -fs HFS+ -volname "${VG_NAME}-tmp" "${{ inputs.tmp-pv-loop-path }}"
+
+        echo "Attaching disk images."
+        # Attach and mount disk images
+        ROOT_DEV=$(hdiutil attach -nobrowse -nomount "${{ inputs.pv-loop-path }}" | awk '{print $1}')
+        TMP_DEV=$(hdiutil attach -nobrowse -nomount "${{ inputs.tmp-pv-loop-path }}" | awk '{print $1}')
+        sudo newfs_hfs -v "${VG_NAME}-root" ${ROOT_DEV}
+        sudo newfs_hfs -v "${VG_NAME}-tmp" ${TMP_DEV}
+
+        echo "Creating build volume"
+        # Mount the root disk image to the build mount path
+        sudo mount -t hfs ${ROOT_DEV} "${BUILD_MOUNT_PATH}"
+        sudo chown -R "${{ inputs.build-mount-path-ownership }}" "${BUILD_MOUNT_PATH}"
+
+        echo "Recreating swap"
+        # Create and activate swap (macOS-specific approach)
+        sudo rm -f /private/var/vm/swapfile
+        sudo dd if=/dev/zero of=/private/var/vm/swapfile bs=1024k count=${{ inputs.swap-size-mb }}
+        sudo chmod 600 /private/var/vm/swapfile
+        sudo /usr/sbin/diskutil secureErase freespace 0 /private/var/vm/swapfile
+        sudo /usr/bin/env fs_usage | grep swap
+
+        # if build mount path is a parent of $GITHUB_WORKSPACE, and has been deleted, recreate it
+        if [[ ! -d "${GITHUB_WORKSPACE}" ]]; then
+          sudo mkdir -p "${GITHUB_WORKSPACE}"
+          sudo chown -R "${WORKSPACE_OWNER}" "${GITHUB_WORKSPACE}"
+        fi
+
+        # Unmount and detach the disk images at the end
+        sudo umount "${BUILD_MOUNT_PATH}"
+        hdiutil detach ${ROOT_DEV}
+        hdiutil detach ${TMP_DEV}
 
     - name: Disk space report after modification
       shell: bash
       run: |
         echo "Memory and swap:"
-        sudo free
-        echo
-        sudo swapon --show
+        vm_stat
         echo
 
         echo "Available storage:"
-        sudo df -h
\ No newline at end of file
+        df -h