diff --git a/src/__Private/execute_async.php b/src/__Private/execute_async.php
index 2ce09f3fa..a96c0d19a 100644
--- a/src/__Private/execute_async.php
+++ b/src/__Private/execute_async.php
@@ -27,6 +27,7 @@
 
   list($stdin, $stdout, $stderr) = $pipes;
   \fclose($stdin);
+  \stream_set_blocking($stdout, false);
 
   $exit_code = -2;
   $output = '';