diff --git a/gnome-panel/gp-module-manager.c b/gnome-panel/gp-module-manager.c
index 58447fd84..7af99de7d 100644
--- a/gnome-panel/gp-module-manager.c
+++ b/gnome-panel/gp-module-manager.c
@@ -49,8 +49,16 @@ load_modules (GpModuleManager *self)
 {
   GDir *dir;
   const gchar *name;
+  const gchar *modules_dir;
 
-  dir = g_dir_open (MODULESDIR, 0, NULL);
+  modules_dir = g_getenv ("NIX_GNOME_PANEL_MODULESDIR");
+
+  if (!modules_dir) {
+    g_warning ("The NIX_GNOME_PANEL_MODULESDIR environment variable was not set, modules will not be loaded.");
+    return;
+  }
+
+  dir = g_dir_open (modules_dir, 0, NULL);
   if (!dir)
     return;
 
@@ -63,7 +71,7 @@ load_modules (GpModuleManager *self)
       if (!g_str_has_suffix (name, ".so"))
         continue;
 
-      path = g_build_filename (MODULESDIR, name, NULL);
+      path = g_build_filename (modules_dir, name, NULL);
       module = gp_module_new_from_path (path);
       g_free (path);