diff --git a/composer.json b/composer.json
index 7e38200..ae7bf76 100644
--- a/composer.json
+++ b/composer.json
@@ -12,7 +12,7 @@
     "http"
   ],
   "require": {
-    "php": "^7.0",
+    "php": "^7.1",
     "psr/http-message": "^1.0",
     "psr/http-server-middleware": "^1.0",
     "psr/http-factory": "^1.0"