diff --git a/CHANGELOG b/CHANGELOG
index 74b691541..381542dbc 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,7 @@
+* 1.6.0-DEV
+
+ * n/a
+
 * 1.5.1 (2012-01-05)
 
  * fixed a regression when parsing strings
diff --git a/composer.json b/composer.json
index 5e107356d..ae833295f 100644
--- a/composer.json
+++ b/composer.json
@@ -4,7 +4,6 @@
     "description": "Twig, the flexible, fast, and secure template language for PHP",
     "keywords": ["templating"],
     "homepage": "http://twig.sensiolabs.org",
-    "version": "1.5.1",
     "license": "BSD",
     "authors": [
         {
diff --git a/ext/twig/php_twig.h b/ext/twig/php_twig.h
index 71b6b0f7e..5467f0328 100644
--- a/ext/twig/php_twig.h
+++ b/ext/twig/php_twig.h
@@ -15,7 +15,7 @@
 #ifndef PHP_TWIG_H
 #define PHP_TWIG_H
 
-#define PHP_TWIG_VERSION "1.5.1"
+#define PHP_TWIG_VERSION "1.6.0-DEV"
 
 #include "php.h"
 
diff --git a/lib/Twig/Environment.php b/lib/Twig/Environment.php
index b11f727de..4ea903aee 100644
--- a/lib/Twig/Environment.php
+++ b/lib/Twig/Environment.php
@@ -17,7 +17,7 @@
  */
 class Twig_Environment
 {
-    const VERSION = '1.5.1';
+    const VERSION = '1.6.0-DEV';
 
     protected $charset;
     protected $loader;