diff --git a/appengine/headless-chrome/app.js b/appengine/headless-chrome/app.js
index 639a2ed6cb..ef19b94db4 100644
--- a/appengine/headless-chrome/app.js
+++ b/appengine/headless-chrome/app.js
@@ -20,40 +20,40 @@ const express = require('express');
 const puppeteer = require('puppeteer');
 const app = express();
 
-let browser;
-
-app.use(async (req, res) => {
-  const {url} = req.query;
-
-  if (!url) {
-    return res.send(
-      'Please provide URL as GET parameter, for example: <a href="/?url=https://example.com">?url=https://example.com</a>'
-    );
-  }
-
-  if (!browser) {
-    // [START gae_std_headless_chrome_full_sample_browser]
-    browser = await puppeteer.launch({
-      args: ['--no-sandbox'],
-    });
-    // [END gae_std_headless_chrome_full_sample_browser]
-  }
-
-  const page = await browser.newPage();
-  await page.goto(url);
-  const imageBuffer = await page.screenshot();
-
-  res.set('Content-Type', 'image/png');
-  res.send(imageBuffer);
-});
-
-const server = app.listen(process.env.PORT || 8080, err => {
-  if (err) {
-    return console.error(err);
-  }
-  const {port} = server.address();
-  console.info(`App listening on port ${port}`);
-});
-// [END gae_std_headless_chrome_full_sample]
+async function main() {
+  // [START gae_std_headless_chrome_full_sample_browser]
+  const browser = await puppeteer.launch({
+    args: ['--no-sandbox'],
+  });
+  // [END gae_std_headless_chrome_full_sample_browser]
+
+  app.use(async (req, res) => {
+    const {url} = req.query;
+
+    if (!url) {
+      return res.send(
+        'Please provide URL as GET parameter, for example: <a href="/?url=https://example.com">?url=https://example.com</a>'
+      );
+    }
+
+    const page = await browser.newPage();
+    await page.goto(url);
+    const imageBuffer = await page.screenshot();
+
+    res.set('Content-Type', 'image/png');
+    res.send(imageBuffer);
+  });
+
+  const server = app.listen(process.env.PORT || 8080, err => {
+    if (err) {
+      return console.error(err);
+    }
+    const {port} = server.address();
+    console.info(`App listening on port ${port}`);
+  });
+  // [END gae_std_headless_chrome_full_sample]
+}
+
+main();
 
 module.exports = app;
diff --git a/appengine/websockets/package.json b/appengine/websockets/package.json
index 42c9c8a4b8..86f188f73a 100644
--- a/appengine/websockets/package.json
+++ b/appengine/websockets/package.json
@@ -23,7 +23,7 @@
   },
   "devDependencies": {
     "@google-cloud/nodejs-repo-tools": "^3.3.0",
-    "eslint": "^5.4.0",
+    "eslint": "^6.0.0",
     "eslint-config-prettier": "^5.0.0",
     "eslint-plugin-node": "^9.0.0",
     "eslint-plugin-prettier": "^3.0.0",
diff --git a/functions/dialogflow/functions/package.json b/functions/dialogflow/functions/package.json
index ec30e50aa5..02c32f0269 100644
--- a/functions/dialogflow/functions/package.json
+++ b/functions/dialogflow/functions/package.json
@@ -19,7 +19,7 @@
   "devDependencies": {
     "@google-cloud/functions-emulator": "^1.0.0-beta.5",
     "@google-cloud/nodejs-repo-tools": "^3.3.0",
-    "eslint": "^5.12.0",
+    "eslint": "^6.0.0",
     "eslint-plugin-promise": "^4.0.1",
     "mocha": "^6.0.2",
     "supertest": "^4.0.0"
diff --git a/functions/headless-chrome/index.js b/functions/headless-chrome/index.js
index 389c28003b..50110ebf64 100644
--- a/functions/headless-chrome/index.js
+++ b/functions/headless-chrome/index.js
@@ -27,6 +27,12 @@ async function getBrowserPage() {
   return browser.newPage();
 }
 
+async function main() {
+  page = await getBrowserPage();
+}
+
+main();
+
 exports.screenshot = async (req, res) => {
   const {url} = req.query;
 
@@ -36,10 +42,6 @@ exports.screenshot = async (req, res) => {
     );
   }
 
-  if (!page) {
-    page = await getBrowserPage();
-  }
-
   await page.goto(url);
   const imageBuffer = await page.screenshot();
   res.set('Content-Type', 'image/png');
diff --git a/iot/beta-features/gateway/gateway.js b/iot/beta-features/gateway/gateway.js
index 605b8fe9e0..d9c2345bd0 100644
--- a/iot/beta-features/gateway/gateway.js
+++ b/iot/beta-features/gateway/gateway.js
@@ -341,18 +341,9 @@ const unbindDeviceFromAllGateways = async (
         };
 
         // for each gateway, make the call to unbind it
-        return new Promise(async (resolve, reject) => {
-          try {
-            await client.projects.locations.registries.unbindDeviceFromGateway(
-              unbindRequest
-            );
-            console.log('Unbound device from gateways', gateway.id);
-            resolve();
-          } catch (err) {
-            console.log('Could not unbind device', err);
-            reject();
-          }
-        });
+        return client.projects.locations.registries.unbindDeviceFromGateway(
+          unbindRequest
+        );
       });
 
       await Promise.all(promises);
diff --git a/package.json b/package.json
index 1197324e47..e9289f294e 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,7 @@
   },
   "devDependencies": {
     "@google-cloud/nodejs-repo-tools": "^3.3.0",
-    "eslint": "^5.9.0",
+    "eslint": "^6.0.0",
     "eslint-config-prettier": "^5.0.0",
     "eslint-plugin-node": "^9.0.0",
     "eslint-plugin-prettier": "^3.1.0",