diff --git a/src/filesystems.sh b/src/filesystems.sh
index e280df9..63d05a0 100644
--- a/src/filesystems.sh
+++ b/src/filesystems.sh
@@ -64,6 +64,18 @@ format_filesystems() {
     local temp_mount
     temp_mount="/tmp/void-wrapper-btrfs"
     mkdir -p "$temp_mount"
+
+    # Ensure cleanup on error
+    cleanup_temp_mount() {
+      if mountpoint -q "$temp_mount" 2>/dev/null; then
+        umount "$temp_mount" || log_warn "Failed to unmount temp mount: $temp_mount"
+      fi
+      if [[ -d "$temp_mount" ]]; then
+        rmdir "$temp_mount" 2>/dev/null || true
+      fi
+    }
+    trap cleanup_temp_mount EXIT
+
     mount "$root_device" "$temp_mount"
     btrfs subvolume create "$temp_mount/@"
     btrfs subvolume create "$temp_mount/@home"
@@ -73,6 +85,7 @@ format_filesystems() {
     btrfs subvolume create "$temp_mount/@swap"
     umount "$temp_mount"
     rmdir "$temp_mount"
+    trap - EXIT
   else
     log_info "Formatting root as ext4 on $root_device"
     mkfs.ext4 -L "$ROOT_LABEL" "$root_device"