diff --git a/.kokoro/functions/billing.cfg b/.kokoro/functions/billing.cfg
index 9668c9d2cb..2c934eb6c2 100644
--- a/.kokoro/functions/billing.cfg
+++ b/.kokoro/functions/billing.cfg
@@ -6,6 +6,12 @@ env_vars: {
     value: "functions/billing"
 }
 
+# Configure the docker image for kokoro-trampoline.
+env_vars: {
+    key: "TRAMPOLINE_IMAGE"
+    value: "gcr.io/cloud-devrel-kokoro-resources/node:8-user"
+}
+
 # Tell the trampoline which build file to use.
 env_vars: {
     key: "TRAMPOLINE_BUILD_FILE"
diff --git a/functions/billing/index.js b/functions/billing/index.js
index ffe433516d..761a202bfc 100644
--- a/functions/billing/index.js
+++ b/functions/billing/index.js
@@ -15,8 +15,8 @@
 
 // [START functions_billing_limit]
 // [START functions_billing_stop]
-const {google} = require('googleapis');
-const {auth} = require('google-auth-library');
+const { google } = require('googleapis');
+const { auth } = require('google-auth-library');
 
 const PROJECT_ID = process.env.GCP_PROJECT;
 const PROJECT_NAME = `projects/${PROJECT_ID}`;
diff --git a/functions/billing/package.json b/functions/billing/package.json
index 1ea72b22d9..13422b2abb 100644
--- a/functions/billing/package.json
+++ b/functions/billing/package.json
@@ -19,6 +19,7 @@
     "@google-cloud/nodejs-repo-tools": "^2.2.5",
     "ava": "^0.25.0",
     "proxyquire": "^2.1.0",
+    "semistandard": "^13.0.0",
     "sinon": "^6.3.4"
   }
 }
diff --git a/functions/billing/test/index.test.js b/functions/billing/test/index.test.js
index ef94be98de..99f672f358 100644
--- a/functions/billing/test/index.test.js
+++ b/functions/billing/test/index.test.js
@@ -98,7 +98,7 @@ function getSample () {
 }
 
 test(`should notify Slack when budget is exceeded`, async t => {
-  const {program, mocks} = getSample();
+  const { program, mocks } = getSample();
 
   const jsonData = { cost: 500, budget: 400 };
   const pubsubData = {
@@ -112,7 +112,7 @@ test(`should notify Slack when budget is exceeded`, async t => {
 });
 
 test(`should disable billing when budget is exceeded`, async t => {
-  const {program, mocks} = getSample();
+  const { program, mocks } = getSample();
 
   const jsonData = { cost: 500, budget: 400 };
   const pubsubData = {
@@ -128,7 +128,7 @@ test(`should disable billing when budget is exceeded`, async t => {
 });
 
 test(`should shut down GCE instances when budget is exceeded`, async t => {
-  const {program, mocks} = getSample();
+  const { program, mocks } = getSample();
 
   const jsonData = { cost: 500, budget: 400 };
   const pubsubData = {