diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 096d494..10386e1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,6 +22,7 @@ jobs:
         - Node.js 7.x
         - Node.js 8.0 # test early async_hooks
         - Node.js 8.x
+        - Node.js 9.x
         - Node.js 10.x
         - Node.js 11.x
         - Node.js 12.x
@@ -80,7 +81,11 @@ jobs:
 
         - name: Node.js 8.x
           node-version: "8.17"
-          npm-i: mocha@7.2.0
+          npm-i: mocha@7.2.0 nyc@14.1.1
+
+        - name: Node.js 9.x
+          node-version: "9.11"
+          npm-i: mocha@7.2.0 nyc@14.1.1
 
         - name: Node.js 10.x
           node-version: "10.24"