--- /dev/null
+<?php
+
+/*
+ * This file is part of the Behat.
+ * (c) Konstantin Kudryashov <ever.zet@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Behat\Behat\Transformation;
+
+use Behat\Testwork\Call\Callee;
+
+/**
+ * Step transformation interface.
+ *
+ * @author Konstantin Kudryashov <ever.zet@gmail.com>
+ */
+interface Transformation extends Callee
+{
+ /**
+ * Returns transformation pattern exactly as it was defined.
+ *
+ * @deprecated Will be removed in 4.0.
+ *
+ * @return string
+ */
+ public function getPattern();
+
+ /**
+ * Represents transformation as a string.
+ *
+ * @return string
+ */
+ public function __toString();
+}