diff --git a/install.sh b/install.sh
index 85d9af8..b4f2836 100755
--- a/install.sh
+++ b/install.sh
@@ -337,7 +337,7 @@ install_dotfiles() {
 
 install_main() {
   test -d ${BASEDIR}/.git && command -v git >/dev/null 2>&1 && \
-    git -C ${BASEDIR} pull
+    git -C ${BASEDIR} pull --ff-only
   test $MINIMAL = 1 || command -v git >/dev/null 2>&1 && \
     git -C ${BASEDIR} submodule update --init --recursive
   test $MINIMAL = 1 || prerequisites