diff --git a/composer.json b/composer.json
index 87567b2..03c6567 100644
--- a/composer.json
+++ b/composer.json
@@ -13,6 +13,7 @@
         "nyholm/psr7": "^1.3",
         "php-http/httplug": "^2.0",
         "psr/http-client": "^1.0",
+        "psr/http-message": "^1.0",
         "symfony/options-resolver": "^2.6 || ^3.4 || ^4.4 || ^5.0 || ^6.0 || ^7.0"
     },
     "require-dev": {