diff --git a/functions/background/index.js b/functions/background/index.js
index 2237056ba9..46fe9e82cf 100644
--- a/functions/background/index.js
+++ b/functions/background/index.js
@@ -21,9 +21,9 @@
  *
  * @param {object} event The Cloud Functions event.
  * @param {object} event.data The event data.
- * @param {function} The callback function.
+ * @param {function} callback The callback function.
  */
-exports.helloWorld = function helloWorld (event, callback) {
+exports.helloWorld = (event, callback) => {
   if (!event.data.myMessage) {
     // This is an error case, "myMessage" is required
     callback(new Error('No message defined!'));
@@ -44,7 +44,7 @@ exports.helloWorld = function helloWorld (event, callback) {
  * @param {object} event.data The event data.
  * @returns {Promise}
  */
-exports.helloPromise = function helloPromise (event) {
+exports.helloPromise = (event) => {
   const request = require('request-promise');
 
   return request({
@@ -61,7 +61,7 @@ exports.helloPromise = function helloPromise (event) {
  * @param {object} event The Cloud Functions event.
  * @param {object} event.data The event data.
  */
-exports.helloSynchronous = function helloSynchronous (event) {
+exports.helloSynchronous = (event) => {
   // This function returns synchronously
   if (event.data.something === true) {
     return 'Something is true!';
diff --git a/functions/datastore/index.js b/functions/datastore/index.js
index 6ff99ff14d..7654ee164d 100644
--- a/functions/datastore/index.js
+++ b/functions/datastore/index.js
@@ -53,7 +53,7 @@ function getKeyFromRequestData (requestData) {
  * @param {object} req.body.value Value to save to Cloud Datastore, e.g. {"description":"Buy milk"}
  * @param {object} res Cloud Function response context.
  */
-exports.set = function set (req, res) {
+exports.set = (req, res) => {
   // The value contains a JSON document representing the entity we want to save
   if (!req.body.value) {
     throw new Error('Value not provided. Make sure you have a "value" property in your request');
@@ -86,7 +86,7 @@ exports.set = function set (req, res) {
  * @param {string} req.body.key Key at which to retrieve the data, e.g. "sampletask1".
  * @param {object} res Cloud Function response context.
  */
-exports.get = function get (req, res) {
+exports.get = (req, res) => {
   const key = getKeyFromRequestData(req.body);
 
   return datastore.get(key)
@@ -118,7 +118,7 @@ exports.get = function get (req, res) {
  * @param {string} req.body.key Key at which to delete data, e.g. "sampletask1".
  * @param {object} res Cloud Function response context.
  */
-exports.del = function del (req, res) {
+exports.del = (req, res) => {
   const key = getKeyFromRequestData(req.body);
 
   // Deletes the entity
diff --git a/functions/errorreporting/index.js b/functions/errorreporting/index.js
index 1913fe32c5..5311d04b4d 100644
--- a/functions/errorreporting/index.js
+++ b/functions/errorreporting/index.js
@@ -70,7 +70,7 @@ function reportError (err, callback) {
  * @param {object} req Cloud Function request context.
  * @param {object} res Cloud Function response context.
  */
-exports.helloSimpleError = function helloSimpleError (req, res) {
+exports.helloSimpleError = (req, res) => {
   try {
     if (req.method !== 'GET') {
       const error = new Error('Only GET requests are accepted!');
@@ -98,7 +98,7 @@ exports.helloSimpleError = function helloSimpleError (req, res) {
  * @param {string} req.body.message Message provided in the request.
  * @param {object} res Cloud Function response context.
  */
-exports.helloHttpError = function helloHttpError (req, res) {
+exports.helloHttpError = (req, res) => {
   try {
     if (req.method !== 'POST' && req.method !== 'GET') {
       const error = new Error('Only POST and GET requests are accepted!');
@@ -126,9 +126,9 @@ exports.helloHttpError = function helloHttpError (req, res) {
  * @param {object} event The Cloud Functions event.
  * @param {object} event.data The event data.
  * @param {string} event.data.message Message, provided by the trigger.
- * @param {function} The callback function.
+ * @param {function} callback The callback function.
  */
-exports.helloBackgroundError = function helloBackgroundError (event, callback) {
+exports.helloBackgroundError = (event, callback) => {
   try {
     if (!event.data.message) {
       throw new Error('"message" is required!');
diff --git a/functions/gcs/index.js b/functions/gcs/index.js
index c2fb86c207..e2424591f8 100644
--- a/functions/gcs/index.js
+++ b/functions/gcs/index.js
@@ -45,9 +45,9 @@ function getFileStream (file) {
  * @param {object} event.data A Google Cloud Storage File object.
  * @param {string} event.data.bucket Name of a Cloud Storage bucket.
  * @param {string} event.data.name Name of a file in the Cloud Storage bucket.
- * @param {function} The callback function.
+ * @param {function} callback The callback function.
  */
-exports.wordCount = function (event, callback) {
+exports.wordCount = (event, callback) => {
   const file = event.data;
 
   if (file.resourceState === 'not_exists') {
diff --git a/functions/helloworld/index.js b/functions/helloworld/index.js
index 0969f2394f..4b92064127 100644
--- a/functions/helloworld/index.js
+++ b/functions/helloworld/index.js
@@ -28,7 +28,7 @@ require('@google-cloud/debug-agent').start();
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloWorld = function helloWorld (event, callback) {
+exports.helloWorld = (event, callback) => {
   console.log(`My Cloud Function: ${event.data.message}`);
   callback();
 };
@@ -41,7 +41,7 @@ exports.helloWorld = function helloWorld (event, callback) {
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.
  */
-exports.helloGET = function helloGET (req, res) {
+exports.helloGET = (req, res) => {
   res.send('Hello World!');
 };
 // [END functions_helloworld_get]
@@ -53,7 +53,7 @@ exports.helloGET = function helloGET (req, res) {
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.
  */
-exports.helloHttp = function helloHttp (req, res) {
+exports.helloHttp = (req, res) => {
   res.send(`Hello ${req.body.name || 'World'}!`);
 };
 // [END functions_helloworld_http]
@@ -65,7 +65,7 @@ exports.helloHttp = function helloHttp (req, res) {
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloBackground = function helloBackground (event, callback) {
+exports.helloBackground = (event, callback) => {
   callback(null, `Hello ${event.data.name || 'World'}!`);
 };
 // [END functions_helloworld_background]
@@ -77,7 +77,7 @@ exports.helloBackground = function helloBackground (event, callback) {
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloPubSub = function (event, callback) {
+exports.helloPubSub = (event, callback) => {
   const pubsubMessage = event.data;
   const name = pubsubMessage.data ? Buffer.from(pubsubMessage.data, 'base64').toString() : 'World';
 
@@ -94,7 +94,7 @@ exports.helloPubSub = function (event, callback) {
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloGCS = function (event, callback) {
+exports.helloGCS = (event, callback) => {
   const file = event.data;
 
   if (file.resourceState === 'not_exists') {
@@ -118,7 +118,7 @@ exports.helloGCS = function (event, callback) {
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloError = function helloError (event, callback) {
+exports.helloError = (event, callback) => {
   // This WILL be reported to Stackdriver errors
   throw new Error('I failed you');
 };
@@ -132,7 +132,7 @@ exports.helloError = function helloError (event, callback) {
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloError2 = function helloError2 (event, callback) {
+exports.helloError2 = (event, callback) => {
   // This will NOT be reported to Stackdriver errors
   throw 1;
 };
@@ -145,7 +145,7 @@ exports.helloError2 = function helloError2 (event, callback) {
  * @param {object} event The Cloud Functions event.
  * @param {function} callback The callback function.
  */
-exports.helloError3 = function helloError3 (event, callback) {
+exports.helloError3 = (event, callback) => {
   // This will NOT be reported to Stackdriver errors
   callback('I failed you');
 };
diff --git a/functions/http/index.js b/functions/http/index.js
index b0aa62d69b..757c4edb57 100644
--- a/functions/http/index.js
+++ b/functions/http/index.js
@@ -22,7 +22,7 @@
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.
  */
-exports.helloWorld = function helloWorld (req, res) {
+exports.helloWorld = (req, res) => {
   if (req.body.message === undefined) {
     // This is an error case, as "message" is required
     res.status(400).send('No message defined!');
@@ -42,7 +42,7 @@ exports.helloWorld = function helloWorld (req, res) {
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.
  */
-exports.helloContent = function helloContent (req, res) {
+exports.helloContent = (req, res) => {
   let name;
 
   switch (req.get('content-type')) {
@@ -91,7 +91,7 @@ function handlePUT (req, res) {
  * @param {Object} req Cloud Function request context.
  * @param {Object} res Cloud Function response context.
  */
-exports.helloHttp = function helloHttp (req, res) {
+exports.helloHttp = (req, res) => {
   switch (req.method) {
     case 'GET':
       handleGET(req, res);
diff --git a/functions/log/index.js b/functions/log/index.js
index 7470ca23b0..5cebd11a78 100644
--- a/functions/log/index.js
+++ b/functions/log/index.js
@@ -16,7 +16,7 @@
 'use strict';
 
 // [START functions_log_helloworld]
-exports.helloWorld = function helloWorld (event, callback) {
+exports.helloWorld = (event, callback) => {
   console.log('I am a log entry!');
   callback();
 };
diff --git a/functions/ocr/app/index.js b/functions/ocr/app/index.js
index 55653cdaa2..0c7e6ed766 100644
--- a/functions/ocr/app/index.js
+++ b/functions/ocr/app/index.js
@@ -109,7 +109,7 @@ function renameImageForSave (filename, lang) {
  * @param {object} event The Cloud Functions event.
  * @param {object} event.data A Google Cloud Storage File object.
  */
-exports.processImage = function processImage (event) {
+exports.processImage = (event) => {
   let file = event.data;
 
   return Promise.resolve()
@@ -144,7 +144,7 @@ exports.processImage = function processImage (event) {
  * @param {string} event.data.data The "data" property of the Cloud Pub/Sub
  * Message. This property will be a base64-encoded string that you must decode.
  */
-exports.translateText = function translateText (event) {
+exports.translateText = (event) => {
   const pubsubMessage = event.data;
   const jsonStr = Buffer.from(pubsubMessage.data, 'base64').toString();
   const payload = JSON.parse(jsonStr);
@@ -194,7 +194,7 @@ exports.translateText = function translateText (event) {
  * @param {string} event.data.data The "data" property of the Cloud Pub/Sub
  * Message. This property will be a base64-encoded string that you must decode.
  */
-exports.saveResult = function saveResult (event) {
+exports.saveResult = (event) => {
   const pubsubMessage = event.data;
   const jsonStr = Buffer.from(pubsubMessage.data, 'base64').toString();
   const payload = JSON.parse(jsonStr);
diff --git a/functions/pubsub/index.js b/functions/pubsub/index.js
index 1ea949c2c0..6957617506 100644
--- a/functions/pubsub/index.js
+++ b/functions/pubsub/index.js
@@ -39,7 +39,7 @@ const Buffer = require('safe-buffer').Buffer;
  * @param {string} req.body.message Message to publish.
  * @param {object} res Cloud Function response context.
  */
-exports.publish = function publish (req, res) {
+exports.publish = (req, res) => {
   if (!req.body.topic) {
     res.status(500).send(new Error('Topic not provided. Make sure you have a "topic" property in your request'));
     return;
@@ -77,9 +77,9 @@ exports.publish = function publish (req, res) {
  * @param {object} event The Cloud Functions event.
  * @param {object} event.data The Cloud Pub/Sub Message object.
  * @param {string} event.data.data The "data" property of the Cloud Pub/Sub Message.
- * @param {function} The callback function.
+ * @param {function} callback The callback function.
  */
-exports.subscribe = function subscribe (event, callback) {
+exports.subscribe = (event, callback) => {
   const pubsubMessage = event.data;
 
   // We're just going to log the message to prove that it worked!
diff --git a/functions/sendgrid/index.js b/functions/sendgrid/index.js
index 12d634f10c..225fb18df4 100644
--- a/functions/sendgrid/index.js
+++ b/functions/sendgrid/index.js
@@ -120,7 +120,7 @@ function getPayload (requestBody) {
  * @param {string} req.body.body Body of the email subject line.
  * @param {object} res Cloud Function response context.
  */
-exports.sendgridEmail = function sendgridEmail (req, res) {
+exports.sendgridEmail = (req, res) => {
   return Promise.resolve()
     .then(() => {
       if (req.method !== 'POST') {
@@ -224,7 +224,7 @@ function fixNames (obj) {
  * @param {object} req Cloud Function request context.
  * @param {object} res Cloud Function response context.
  */
-exports.sendgridWebhook = function sendgridWebhook (req, res) {
+exports.sendgridWebhook = (req, res) => {
   return Promise.resolve()
     .then(() => {
       if (req.method !== 'POST') {
@@ -291,7 +291,7 @@ function getTable () {
  * @param {string} [event.data.timeDeleted] Time the file was deleted if this is a deletion event.
  * @see https://cloud.google.com/storage/docs/json_api/v1/objects#resource
  */
-exports.sendgridLoad = function sendgridLoad (event) {
+exports.sendgridLoad = (event) => {
   const file = event.data;
 
   if (file.resourceState === 'not_exists') {
diff --git a/functions/sendgrid/test/index.test.js b/functions/sendgrid/test/index.test.js
index fa750ca74e..39ed1ae26f 100644
--- a/functions/sendgrid/test/index.test.js
+++ b/functions/sendgrid/test/index.test.js
@@ -113,7 +113,7 @@ function getSample () {
 }
 
 function getMocks () {
-  var req = {
+  let req = {
     headers: {},
     query: {},
     body: {},
@@ -122,7 +122,7 @@ function getMocks () {
     }
   };
   sinon.spy(req, 'get');
-  var res = {
+  let res = {
     headers: {},
     send: sinon.stub().returnsThis(),
     json: sinon.stub().returnsThis(),
diff --git a/functions/slack/index.js b/functions/slack/index.js
index a06180c4fb..534f7d31de 100644
--- a/functions/slack/index.js
+++ b/functions/slack/index.js
@@ -137,7 +137,7 @@ function makeSearchRequest (query) {
  * @param {string} req.body.text The user's search query.
  * @param {object} res Cloud Function response object.
  */
-exports.kgSearch = function kgSearch (req, res) {
+exports.kgSearch = (req, res) => {
   return Promise.resolve()
     .then(() => {
       if (req.method !== 'POST') {
diff --git a/functions/uuid/index.js b/functions/uuid/index.js
index 3ac049d45d..889bf1d801 100644
--- a/functions/uuid/index.js
+++ b/functions/uuid/index.js
@@ -19,7 +19,7 @@
 const uuid = require('uuid');
 
 // Return a newly generated UUID in the HTTP response.
-exports.getUuid = function (req, res) {
+exports.getUuid = (req, res) => {
   res.send(uuid.v4());
 };
 // [END functions_uuid]