diff --git a/packages/w3up-client/package.json b/packages/w3up-client/package.json
index 4c6a42b9a..ba61435cc 100644
--- a/packages/w3up-client/package.json
+++ b/packages/w3up-client/package.json
@@ -178,5 +178,9 @@
       "assert",
       "c8"
     ]
-  }
+  },
+  "engines": {
+    "node": ">=18"
+  },
+  "engineStrict": true
 }