diff --git a/src/commands/AbstractBaseCommand.php b/src/commands/AbstractBaseCommand.php
index 8907827..ff19c16 100644
--- a/src/commands/AbstractBaseCommand.php
+++ b/src/commands/AbstractBaseCommand.php
@@ -88,7 +88,8 @@ protected function setRunwayConfigValue(string $key, $value): void {
      *
      * @return $this
      */
-    public function addOption(string $name, $shortcut = null, int $mode = null, string $description = '', $default = null): self {
+    public function addOption(string $name, $shortcut = null, ?int $mode = null, string $description = '', $default = null): self
+    {
         // Build raw option format Ahc\Cli expects, e.g. "-s, --name" or "--name"
         $raw = '';
 
@@ -139,7 +140,8 @@ public function addOption(string $name, $shortcut = null, int $mode = null, stri
      *
      * @return $this
      */
-    public function addArgument(string $name, int $mode = null, string $description = '', $default = null): self {
+    public function addArgument(string $name, ?int $mode = null, string $description = '', $default = null): self
+    {
         if ($mode === null) {
             $mode = self::OPTIONAL;
         }