diff --git a/composer.json b/composer.json
index 318f710..18d8b69 100644
--- a/composer.json
+++ b/composer.json
@@ -39,7 +39,7 @@
     "ext-json": "*",
     "adriansuter/php-autoload-override": "^1.3",
     "http-interop/http-factory-tests": "^0.9.0",
-    "php-http/psr7-integration-tests": "dev-master",
+    "php-http/psr7-integration-tests": "1.1",
     "phpspec/prophecy": "^1.15",
     "phpspec/prophecy-phpunit": "^2.0",
     "phpstan/phpstan": "^1.8",
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index ccac1b2..5bd758d 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -1,5 +1,6 @@
 parameters:
   level: max
   checkMissingIterableValueType: false
+  treatPhpDocTypesAsCertain: false
   paths:
     - src