diff --git a/src/Writer/Stream.php b/src/Writer/Stream.php
index da15896..21784c7 100644
--- a/src/Writer/Stream.php
+++ b/src/Writer/Stream.php
@@ -30,6 +30,8 @@
 
 class Stream extends AbstractWriter
 {
+    private const DEFAULT_PERMISSIONS = 0666;
+
     /**
      * Separator between log entries
      */
@@ -47,7 +49,7 @@ public function __construct(
         mixed $streamOrUrl,
         ?string $mode = null,
         ?string $logSeparator = null,
-        ?int $filePermissions = null
+        ?int $filePermissions = self::DEFAULT_PERMISSIONS,
     ) {
         if ($streamOrUrl instanceof Traversable) {
             $streamOrUrl = iterator_to_array($streamOrUrl);