diff --git a/lib/memory-engine.js b/lib/memory-engine.js
index <HASH>..<HASH> 100644
--- a/lib/memory-engine.js
+++ b/lib/memory-engine.js
@@ -79,6 +79,25 @@ module.exports = function(options) {
     return callback(null);
   }
 
+  /**
+   * Deletes one object. Returns an error if the object can not be found
+   * or if the ID property is not present.
+   *
+   * @param {Object} object to delete
+   * @param {Function} callback
+   * @api public
+   */
+  function deleteOne(object, callback) {
+    checkForIdAndData(object, function(error) {
+      if (error) {
+        return callback(error);
+      }
+
+      delete data[object[options.idProperty]];
+      callback(undefined);
+    });
+  }
+
   return (
     { create: function(object, callback) {
         object = _.clone(object);
@@ -116,16 +135,7 @@ module.exports = function(options) {
         });
 
       }
-    , deleteOne: function(object, callback) {
-        checkForIdAndData(object, function(error) {
-          if (error) {
-            return callback(error);
-          }
-
-          delete data[object[options.idProperty]];
-          callback(undefined);
-        });
-      }
+    , deleteOne: deleteOne
     , find: find
     , findOne: function(query, options, callback) {
         find(query, options, function(error, objects) {
Move `deleteOne` out of returned object and add comments