diff --git a/src/EntityReferenceRevisionsServiceProvider.php b/src/EntityReferenceRevisionsServiceProvider.php
index b5d3310..304bde9 100644
--- a/src/EntityReferenceRevisionsServiceProvider.php
+++ b/src/EntityReferenceRevisionsServiceProvider.php
@@ -17,7 +17,7 @@ class EntityReferenceRevisionsServiceProvider extends ServiceProviderBase {
    */
   public function alter(ContainerBuilder $container) {
     $modules = $container->getParameter('container.modules');
-    if (isset($modules['hal'])) {
+    if (isset($modules['hal']) && isset($modules['rest'])) {
       // Hal module is enabled, add our new normalizer for entity reference
       // revision items.
       $service_definition = new Definition('Drupal\entity_reference_revisions\Normalizer\EntityReferenceRevisionItemNormalizer', array(