diff --git a/h5p-default-storage.class.php b/h5p-default-storage.class.php
index 38af307..26e3e01 100644
--- a/h5p-default-storage.class.php
+++ b/h5p-default-storage.class.php
@@ -451,6 +451,19 @@ class H5PDefaultStorage implements \H5PFileStorage {
     return self::dirReady($this->path);
   }
 
+  /**
+   * Check if the file presave.js exists in the root of the library
+   *
+   * @param string $libraryFolder
+   * @param string $developmentPath
+   * @return bool
+   */
+  public function hasPresave($libraryFolder, $developmentPath = null) {
+      $path = is_null($developmentPath) ? 'libraries' . DIRECTORY_SEPARATOR . $libraryFolder : $developmentPath;
+      $filePath = realpath($this->path . DIRECTORY_SEPARATOR . $path . DIRECTORY_SEPARATOR . 'presave.js');
+    return file_exists($filePath);
+  }
+
   /**
    * Recursive function for copying directories.
    *
diff --git a/h5p-file-storage.interface.php b/h5p-file-storage.interface.php
index 394210b..4dbdbc6 100644
--- a/h5p-file-storage.interface.php
+++ b/h5p-file-storage.interface.php
@@ -190,4 +190,13 @@ interface H5PFileStorage {
    * @return bool True if server has the proper write access
    */
   public function hasWriteAccess();
+
+  /**
+   * Check if the library has a presave.js in the root folder
+   *
+   * @param string $libraryName
+   * @param string $developmentPath
+   * @return bool
+   */
+  public function hasPresave($libraryName, $developmentPath = null);
 }