diff --git a/install.sh b/install.sh
index 49feb26..9040e65 100755
--- a/install.sh
+++ b/install.sh
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-[ "$(whoami)" != "root" ] && echo "Error: installation only works as root!" >&2 && exit 1
+(( EUID != 0 )) && echo "Error: installation only works as root!" >&2 && exit 1
 
 API_ENDPOINT="https://git.ccc-rheintal.ch/api/v1/repos/spacefreak/pbc"
 
diff --git a/pbc b/pbc
index f1ab402..2f0ede3 100755
--- a/pbc
+++ b/pbc
@@ -394,7 +394,7 @@ case "$action" in
   install)
     update=${args[0]:-false}
 
-    [ "$(whoami)" != "root" ] && echo "Error: installation only works as root!" >&2 && exit 1
+    (( EUID != 0 )) && echo "Error: installation only works as root!" >&2 && exit 1
 
     install_proxmox_backup_client "$update" || exit $?