sokil
diff --git a/‎composer.json
+4 b/‎composer.json
+4
@@ -8,8 +8,12 @@
         }
     ],
     "require": {
+        "php": "^5.6",
         "sebastian/diff": "^1.4"
     },
+    "require-dev": {
+        "phpunit/phpunit": "5.4.*"
+    },
     "autoload": {
         "psr-4": {
             "Sokil\\Diff\\": "src/"