diff --git a/composer.json b/composer.json
index 5370b1f..74e4a47 100644
--- a/composer.json
+++ b/composer.json
@@ -24,9 +24,9 @@
     "dealerdirect/phpcodesniffer-composer-installer": "^0.7",
     "matthiasmullie/minify": "^1.3",
     "phpcompatibility/phpcompatibility-wp": "^2.1",
-    "phpunit/phpunit": "^5|^6|^7|^8",
+    "phpunit/phpunit": "^5|^6|^7|^8|^9",
     "slowprog/composer-copy-file": "~0.3",
-    "squizlabs/php_codesniffer": "^3.6",
+    "squizlabs/php_codesniffer": "^3.7",
     "wp-coding-standards/wpcs": "^2.3",
     "yoast/phpunit-polyfills": "^1.0"
   },
diff --git a/package.json b/package.json
index ff56bac..16c6693 100644
--- a/package.json
+++ b/package.json
@@ -5,8 +5,8 @@
   "author": "Stefan Kalscheuer",
   "license": "GPL-2.0+",
   "devDependencies": {
-    "@wordpress/eslint-plugin": "^12",
-    "@wordpress/stylelint-config": "^20",
+    "@wordpress/eslint-plugin": "^13",
+    "@wordpress/stylelint-config": "^21",
     "eslint": "^8",
     "stylelint": "^14"
   }