diff --git a/src/appdb.js b/src/appdb.js
index 5d5d648b3..21788649b 100644
--- a/src/appdb.js
+++ b/src/appdb.js
@@ -498,7 +498,7 @@ function getAppStoreIds(callback) {
 function setAddonConfig(appId, addonId, env, callback) {
     assert.strictEqual(typeof appId, 'string');
     assert.strictEqual(typeof addonId, 'string');
-    assert(util.isArray(env));
+    assert(Array.isArray(env));
     assert.strictEqual(typeof callback, 'function');
 
     unsetAddonConfig(appId, addonId, function (error) {
diff --git a/src/apps.js b/src/apps.js
index ae0771b5e..d1d7c4aa4 100644
--- a/src/apps.js
+++ b/src/apps.js
@@ -1833,7 +1833,7 @@ function exec(app, options, callback) {
     assert.strictEqual(typeof callback, 'function');
 
     var cmd = options.cmd || [ '/bin/bash' ];
-    assert(util.isArray(cmd) && cmd.length > 0);
+    assert(Array.isArray(cmd) && cmd.length > 0);
 
     if (app.installationState !== exports.ISTATE_INSTALLED || app.runState !== exports.RSTATE_RUNNING) {
         return callback(new BoxError(BoxError.BAD_STATE, 'App not installed or running'));
diff --git a/src/backupdb.js b/src/backupdb.js
index 541d93d14..e012a4767 100644
--- a/src/backupdb.js
+++ b/src/backupdb.js
@@ -119,7 +119,7 @@ function add(id, data, callback) {
     assert.strictEqual(typeof data.type, 'string');
     assert.strictEqual(typeof data.identifier, 'string');
     assert.strictEqual(typeof data.state, 'string');
-    assert(util.isArray(data.dependsOn));
+    assert(Array.isArray(data.dependsOn));
     assert.strictEqual(typeof data.manifest, 'object');
     assert.strictEqual(typeof data.format, 'string');
     assert.strictEqual(typeof callback, 'function');
diff --git a/src/database.js b/src/database.js
index 963c26786..020e5a26c 100644
--- a/src/database.js
+++ b/src/database.js
@@ -96,7 +96,7 @@ function query() {
 }
 
 function transaction(queries, callback) {
-    assert(util.isArray(queries));
+    assert(Array.isArray(queries));
     assert.strictEqual(typeof callback, 'function');
 
     callback = once(callback);
diff --git a/src/dns/cloudflare.js b/src/dns/cloudflare.js
index b0c32dc34..36dabfb30 100644
--- a/src/dns/cloudflare.js
+++ b/src/dns/cloudflare.js
@@ -110,7 +110,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -206,7 +206,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/digitalocean.js b/src/dns/digitalocean.js
index 54f826811..e97daf784 100644
--- a/src/dns/digitalocean.js
+++ b/src/dns/digitalocean.js
@@ -82,7 +82,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -185,7 +185,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/gandi.js b/src/dns/gandi.js
index 0b500698b..ea6281dac 100644
--- a/src/dns/gandi.js
+++ b/src/dns/gandi.js
@@ -39,7 +39,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -98,7 +98,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/gcdns.js b/src/dns/gcdns.js
index a83de3518..109962fe6 100644
--- a/src/dns/gcdns.js
+++ b/src/dns/gcdns.js
@@ -73,7 +73,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -144,7 +144,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/godaddy.js b/src/dns/godaddy.js
index 0a3a24c85..3e339d344 100644
--- a/src/dns/godaddy.js
+++ b/src/dns/godaddy.js
@@ -45,7 +45,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -118,7 +118,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/interface.js b/src/dns/interface.js
index 1651d8e5c..963fc523d 100644
--- a/src/dns/interface.js
+++ b/src/dns/interface.js
@@ -34,7 +34,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     // Result: none
@@ -57,7 +57,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     // Result: none
diff --git a/src/dns/linode.js b/src/dns/linode.js
index 94133a4bf..f0299f153 100644
--- a/src/dns/linode.js
+++ b/src/dns/linode.js
@@ -135,7 +135,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -217,7 +217,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/manual.js b/src/dns/manual.js
index 893ce2c83..0398521c6 100644
--- a/src/dns/manual.js
+++ b/src/dns/manual.js
@@ -31,7 +31,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     debug('upsert: %s for zone %s of type %s with values %j', location, domainObject.zoneName, type, values);
@@ -52,7 +52,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     return callback();
diff --git a/src/dns/namecom.js b/src/dns/namecom.js
index b2a8ce32d..6a1298e5a 100644
--- a/src/dns/namecom.js
+++ b/src/dns/namecom.js
@@ -157,7 +157,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -200,7 +200,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/netcup.js b/src/dns/netcup.js
index 351334ef5..adc59b186 100644
--- a/src/dns/netcup.js
+++ b/src/dns/netcup.js
@@ -90,7 +90,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -183,7 +183,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/noop.js b/src/dns/noop.js
index 83b5c951b..ed6efe119 100644
--- a/src/dns/noop.js
+++ b/src/dns/noop.js
@@ -26,7 +26,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     debug('upsert: %s for zone %s of type %s with values %j', location, domainObject.zoneName, type, values);
@@ -47,7 +47,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     return callback();
diff --git a/src/dns/route53.js b/src/dns/route53.js
index 9ef67b71a..413edd58e 100644
--- a/src/dns/route53.js
+++ b/src/dns/route53.js
@@ -97,7 +97,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
@@ -178,7 +178,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     const dnsConfig = domainObject.config,
diff --git a/src/dns/wildcard.js b/src/dns/wildcard.js
index fc1e5058c..7930c676e 100644
--- a/src/dns/wildcard.js
+++ b/src/dns/wildcard.js
@@ -31,7 +31,7 @@ function upsert(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     debug('upsert: %s for zone %s of type %s with values %j', location, domainObject.zoneName, type, values);
@@ -52,7 +52,7 @@ function del(domainObject, location, type, values, callback) {
     assert.strictEqual(typeof domainObject, 'object');
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     return callback();
diff --git a/src/docker.js b/src/docker.js
index 8a6afece6..6bca8e645 100644
--- a/src/docker.js
+++ b/src/docker.js
@@ -303,7 +303,7 @@ function getLowerUpIp() { // see getifaddrs and IFF_LOWER_UP and netdevice
 function createSubcontainer(app, name, cmd, options, callback) {
     assert.strictEqual(typeof app, 'object');
     assert.strictEqual(typeof name, 'string');
-    assert(!cmd || util.isArray(cmd));
+    assert(!cmd || Array.isArray(cmd));
     assert.strictEqual(typeof options, 'object');
     assert.strictEqual(typeof callback, 'function');
 
diff --git a/src/domains.js b/src/domains.js
index 372c86072..ea5105756 100644
--- a/src/domains.js
+++ b/src/domains.js
@@ -398,7 +398,7 @@ function upsertDnsRecords(location, domain, type, values, callback) {
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof domain, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     debug('upsertDNSRecord: %s on %s type %s values', location, domain, type, values);
@@ -418,7 +418,7 @@ function removeDnsRecords(location, domain, type, values, callback) {
     assert.strictEqual(typeof location, 'string');
     assert.strictEqual(typeof domain, 'string');
     assert.strictEqual(typeof type, 'string');
-    assert(util.isArray(values));
+    assert(Array.isArray(values));
     assert.strictEqual(typeof callback, 'function');
 
     debug('removeDNSRecord: %s on %s type %s values', location, domain, type, values);
diff --git a/src/eventlog.js b/src/eventlog.js
index 4f69a7bfa..b39cfa33a 100644
--- a/src/eventlog.js
+++ b/src/eventlog.js
@@ -75,14 +75,14 @@ exports = module.exports = {
     ACTION_PROCESS_CRASH: 'system.crash'
 };
 
-var assert = require('assert'),
+const assert = require('assert'),
     debug = require('debug')('box:eventlog'),
     eventlogdb = require('./eventlogdb.js'),
     notifications = require('./notifications.js'),
     util = require('util'),
     uuid = require('uuid');
 
-var NOOP_CALLBACK = function (error) { if (error) debug(error); };
+const NOOP_CALLBACK = function (error) { if (error) debug(error); };
 
 function add(action, source, data, callback) {
     assert.strictEqual(typeof action, 'string');
@@ -144,7 +144,7 @@ function getAllPaged(actions, search, page, perPage, callback) {
 }
 
 function getByCreationTime(creationTime, callback) {
-    assert(util.isDate(creationTime));
+    assert(util.types.isDate(creationTime));
     assert.strictEqual(typeof callback, 'function');
 
     eventlogdb.getByCreationTime(creationTime, function (error, events) {
diff --git a/src/eventlogdb.js b/src/eventlogdb.js
index 53266dea3..749607411 100644
--- a/src/eventlogdb.js
+++ b/src/eventlogdb.js
@@ -12,7 +12,7 @@ exports = module.exports = {
     _clear: clear
 };
 
-var assert = require('assert'),
+const assert = require('assert'),
     async = require('async'),
     BoxError = require('./boxerror.js'),
     database = require('./database.js'),
@@ -20,7 +20,7 @@ var assert = require('assert'),
     safe = require('safetydance'),
     util = require('util');
 
-var EVENTLOG_FIELDS = [ 'id', 'action', 'source', 'data', 'creationTime' ].join(',');
+const EVENTLOG_FIELDS = [ 'id', 'action', 'source', 'data', 'creationTime' ].join(',');
 
 function postProcess(eventLog) {
     // usually we have sourceJson and dataJson, however since this used to be the JSON data type, we don't
@@ -77,7 +77,7 @@ function getAllPaged(actions, search, page, perPage, callback) {
 }
 
 function getByCreationTime(creationTime, callback) {
-    assert(util.isDate(creationTime));
+    assert(util.types.isDate(creationTime));
     assert.strictEqual(typeof callback, 'function');
 
     var query = 'SELECT ' + EVENTLOG_FIELDS + ' FROM eventlog WHERE creationTime >= ? ORDER BY creationTime DESC';
@@ -150,7 +150,7 @@ function clear(callback) {
 }
 
 function delByCreationTime(creationTime, callback) {
-    assert(util.isDate(creationTime));
+    assert(util.types.isDate(creationTime));
     assert.strictEqual(typeof callback, 'function');
 
     // remove notifications that reference the events as well
diff --git a/src/mailboxdb.js b/src/mailboxdb.js
index e32d5be71..4b2540c30 100644
--- a/src/mailboxdb.js
+++ b/src/mailboxdb.js
@@ -348,7 +348,7 @@ function getByOwnerId(ownerId, callback) {
 function setAliasesForName(name, domain, aliases, callback) {
     assert.strictEqual(typeof name, 'string');
     assert.strictEqual(typeof domain, 'string');
-    assert(util.isArray(aliases));
+    assert(Array.isArray(aliases));
     assert.strictEqual(typeof callback, 'function');
 
     database.query('SELECT ' + MAILBOX_FIELDS + ' FROM mailboxes WHERE name = ? AND domain = ?', [ name, domain ], function (error, results) {
diff --git a/src/routes/apps.js b/src/routes/apps.js
index 8aec08a2a..14b9e13eb 100644
--- a/src/routes/apps.js
+++ b/src/routes/apps.js
@@ -662,7 +662,7 @@ function exec(req, res, next) {
     var cmd = null;
     if (req.query.cmd) {
         cmd = safe.JSON.parse(req.query.cmd);
-        if (!util.isArray(cmd) || cmd.length < 1) return next(new HttpError(400, 'cmd must be array with atleast size 1'));
+        if (!Array.isArray(cmd) || cmd.length < 1) return next(new HttpError(400, 'cmd must be array with atleast size 1'));
     }
 
     var columns = req.query.columns ? parseInt(req.query.columns, 10) : null;
@@ -703,7 +703,7 @@ function execWebSocket(req, res, next) {
     var cmd = null;
     if (req.query.cmd) {
         cmd = safe.JSON.parse(req.query.cmd);
-        if (!util.isArray(cmd) || cmd.length < 1) return next(new HttpError(400, 'cmd must be array with atleast size 1'));
+        if (!Array.isArray(cmd) || cmd.length < 1) return next(new HttpError(400, 'cmd must be array with atleast size 1'));
     }
 
     var columns = req.query.columns ? parseInt(req.query.columns, 10) : null;
diff --git a/src/shell.js b/src/shell.js
index 8a7d4a8d5..fd923a97e 100644
--- a/src/shell.js
+++ b/src/shell.js
@@ -35,7 +35,7 @@ function exec(tag, cmd, callback) {
 function spawn(tag, file, args, options, callback) {
     assert.strictEqual(typeof tag, 'string');
     assert.strictEqual(typeof file, 'string');
-    assert(util.isArray(args));
+    assert(Array.isArray(args));
     assert.strictEqual(typeof options, 'object');
     assert.strictEqual(typeof callback, 'function');
 
@@ -80,7 +80,7 @@ function spawn(tag, file, args, options, callback) {
 
 function sudo(tag, args, options, callback) {
     assert.strictEqual(typeof tag, 'string');
-    assert(util.isArray(args));
+    assert(Array.isArray(args));
     assert.strictEqual(typeof options, 'object');
     assert.strictEqual(typeof callback, 'function');
 
diff --git a/src/test/dns-test.js b/src/test/dns-test.js
index 0ba49ba4f..6b5e012c4 100644
--- a/src/test/dns-test.js
+++ b/src/test/dns-test.js
@@ -1025,7 +1025,7 @@ describe('dns provider', function () {
                     expect(options).to.be.an(Object);
 
                     var elem = queue.shift();
-                    if (!util.isArray(elem)) throw (new Error('Mock answer required'));
+                    if (!Array.isArray(elem)) throw (new Error('Mock answer required'));
 
                     // if no callback passed, return a req object with send();
                     if (typeof callback !== 'function') {
@@ -1184,7 +1184,7 @@ describe('dns provider', function () {
                     var callback = arguments[--arguments.length];
 
                     var elem = queue.shift();
-                    if (!util.isArray(elem)) throw (new Error('Mock answer required'));
+                    if (!Array.isArray(elem)) throw (new Error('Mock answer required'));
 
                     // if no callback passed, return a req object with send();
                     if (typeof callback !== 'function') {