diff --git a/scripts/_common.sh b/scripts/_common.sh
index 179e4f2..b546e94 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -16,4 +16,17 @@ nodejs_version="12"
 
 #=================================================
 # FUTURE OFFICIAL HELPERS
-#=================================================
\ No newline at end of file
+#=================================================
+
+# Execute a command as another user
+# usage: ynh_exec_as USER COMMAND [ARG ...]
+ynh_exec_as() {
+  local USER=$1
+  shift 1
+
+  if [[ $USER = $(whoami) ]]; then
+    eval "$@"
+  else
+    sudo -u "$USER" "$@"
+  fi
+}
diff --git a/scripts/upgrade b/scripts/upgrade
index 6a281ef..6df1a11 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -86,7 +86,7 @@ then
 	#ynh_setup_source --dest_dir="$final_path"
 
 	pushd $final_path
-		bower update
+		ynh_exec_warn_less ynh_exec_as $app bower update
 	popd
 fi