diff --git a/src/Request.php b/src/Request.php
index 74713691..396fbd46 100644
--- a/src/Request.php
+++ b/src/Request.php
@@ -282,6 +282,6 @@ public function buildSignature(
      */
     public static function generateNonce(): string
     {
-        return md5(microtime() . random_int());
+        return md5(microtime() . random_int(PHP_INT_MIN, PHP_INT_MAX));
     }
 }
diff --git a/tests/mocks.php b/tests/mocks.php
index dcaee6c5..26d79352 100644
--- a/tests/mocks.php
+++ b/tests/mocks.php
@@ -15,7 +15,7 @@ function microtime()
     return 'FAKE_MICROTIME';
 }
 
-function random_int()
+function random_int($_min, $_max)
 {
     return 123_456_789;
 }