diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index b387561..50533f8 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        serverless: ['1', '2', '3']
+        serverless: ['1', '2', '3', '4']
         node: [ '14', '15', '16', '18', '19', '20', '21' ]
     name: CI (Node v${{ matrix.node }}, serverless@${{ matrix.serverless }})
     steps:
diff --git a/package.json b/package.json
index d6ee455..7a8b851 100644
--- a/package.json
+++ b/package.json
@@ -46,6 +46,6 @@
     "sinon-chai": "^3.7.0"
   },
   "peerDependencies": {
-    "serverless": "1 || 2 || pre-3 || 3"
+    "serverless": "1 || 2 || pre-3 || 3 || 4"
   }
 }