diff --git a/composer.json b/composer.json
index 0cf1b27..75fd709 100644
--- a/composer.json
+++ b/composer.json
@@ -19,10 +19,10 @@
         "codacy/coverage": "^1.4",
         "league/pipeline": "^1.0|^0.3",
         "phan/phan": "^0.12",
-        "infection/infection": "^0.9",
-        "phpstan/phpstan": "^0.10",
+        "infection/infection": "~0.8",
+        "phpstan/phpstan": "~0.9",
         "mockery/mockery": "^1.0",
-        "vimeo/psalm": "^2.0"
+        "vimeo/psalm": ">=1.1"
     },
     "license": "Apache-2.0",
     "minimum-stability": "dev",