diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 3c59690..83dbe1e 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -243,7 +243,7 @@ jobs:
     name: PHPUnit ${{ matrix.phpunit-version }} on PHP ${{ matrix.php-version }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           ref: ${{ github.head_ref }}
 
diff --git a/composer.json b/composer.json
index 406f8cb..ef911d4 100644
--- a/composer.json
+++ b/composer.json
@@ -22,6 +22,9 @@
         "phpunit/phpunit": "^6 || ^7 || ^8 || ^9",
         "php-mock/php-mock-integration": "^2.1"
     },
+    "require-dev": {
+        "phpspec/prophecy": "^1.10.3"
+    },
     "archive": {
         "exclude": ["/tests"]
     }