diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index aa76a5a..9d2bc6e 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -12,6 +12,7 @@ jobs:
     strategy:
       matrix:
         node-version: [16.x, 18.x, 20.x]
+        nodemailer: [4, 5, 6]
     steps:
       - uses: actions/checkout@v3