diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index ec8157456..9f6fa5d04 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -605,7 +605,7 @@ class Installer
                 $this->eventDispatcher->dispatchPackageEvent(constant($event), $this->devMode, $policy, $pool, $installedRepo, $request, $operations, $operation);
             }
 
-            if ($this->executeOperations) {
+            if ($this->executeOperations || $this->writeLock) {
                 $localRepo->write();
             }
         }