diff --git a/src/Storm/FileSystem/Abstract.php b/src/Storm/FileSystem/Abstract.php
index 397b679d9ffed3e91124808303f9d632b520b725..692128d01269b878a59c84210fc0a18e4334ab9e 100644
--- a/src/Storm/FileSystem/Abstract.php
+++ b/src/Storm/FileSystem/Abstract.php
@@ -51,4 +51,6 @@ abstract class Storm_FileSystem_Abstract {
   abstract public function delete(string $path) : bool;
 
   abstract public function readfile(string $path);
+
+  abstract public function mkdir($path);
 }
diff --git a/src/Storm/FileSystem/Disk.php b/src/Storm/FileSystem/Disk.php
index abc2880345f37af0b40a03b4795294731239f9ea..9618b9f866ae877131bf45dfdad136acab070135 100644
--- a/src/Storm/FileSystem/Disk.php
+++ b/src/Storm/FileSystem/Disk.php
@@ -25,6 +25,11 @@ THE SOFTWARE.
 */
 
 class Storm_FileSystem_Disk extends Storm_FileSystem_Abstract {
+  public function mkdir($path) {
+    return mkdir($path);
+  }
+
+
   public function fileExists($path) {
     return file_exists($path);
   }