diff --git a/composer.json b/composer.json
index ae3e2d4..e1016af 100644
--- a/composer.json
+++ b/composer.json
@@ -34,7 +34,7 @@
     },
     "require-dev": {
         "httpwg/structured-field-tests": "*@dev",
-        "paragonie/constant_time_encoding": "^2.6.3",
+        "paragonie/constant_time_encoding": "^2.6.3 || ^3.0.0",
         "phpmd/phpmd": "^2.15",
         "phpstan/phpstan": "^1.9",
         "phpstan/phpstan-phpunit": "^1.3",