diff --git a/src/moduleutils/PhutilLibraryMapBuilder.php b/src/moduleutils/PhutilLibraryMapBuilder.php
index 5d359bbc..7997bf57 100644
--- a/src/moduleutils/PhutilLibraryMapBuilder.php
+++ b/src/moduleutils/PhutilLibraryMapBuilder.php
@@ -212,7 +212,7 @@ final class PhutilLibraryMapBuilder extends Phobject {
   /**
    * Drop the symbol cache, forcing a clean rebuild.
    *
-   * @return this
+   * @return void
    *
    * @task symbol
    */