diff --git a/buildbot/buildbot_steps.sh b/buildbot/buildbot_steps.sh
index 7059619..92f58a9 100755
--- a/buildbot/buildbot_steps.sh
+++ b/buildbot/buildbot_steps.sh
@@ -38,10 +38,10 @@ function sed_enabled_ipxe_features() {
                   NTP_CMD \
                   CERT_CMD
         do
-        sed -ri \
+        sed -i -r \
           "s/^\\/+#define[[:space:]]+$OPTION[[:space:]]/#define $OPTION /g" \
           "${ipxe_src_dir}/src/config/general.h"
-	sed -ri
+	sed -i -r \
           "s/^#undef[[:space:]]+$OPTION[[:space:]]/#define $OPTION /g" \
           "${ipxe_src_dir}/src/config/general.h"
     done