diff --git a/lib/server.js b/lib/server.js
index 1f2054e26..e4b2c2e5a 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -17,7 +17,7 @@ const constant = require('./constants')
 const watcher = require('./watcher')
 const plugin = require('./plugin')
 
-const ws = require('./web-server')
+const createWebServer = require('./web-server').createWebServer
 const preprocessor = require('./preprocessor')
 const Launcher = require('./launcher').Launcher
 const FileList = require('./file-list')
@@ -68,7 +68,7 @@ class Server extends KarmaEventEmitter {
       config: ['value', config],
       preprocess: ['factory', preprocessor.createPreprocessor],
       fileList: ['factory', FileList.factory],
-      webServer: ['factory', ws.create],
+      webServer: ['factory', createWebServer],
       socketServer: ['factory', createSocketIoServer],
       executor: ['factory', Executor.factory],
       // TODO(vojta): remove
diff --git a/lib/web-server.js b/lib/web-server.js
index 8df084d5d..9534ff9a9 100644
--- a/lib/web-server.js
+++ b/lib/web-server.js
@@ -1,49 +1,45 @@
-var fs = require('graceful-fs')
-var http = require('http')
-var https = require('https')
-var path = require('path')
-var connect = require('connect')
-var Promise = require('bluebird')
-
-var common = require('./middleware/common')
-var runnerMiddleware = require('./middleware/runner')
-var stopperMiddleware = require('./middleware/stopper')
-var stripHostMiddleware = require('./middleware/strip_host')
-var karmaMiddleware = require('./middleware/karma')
-var sourceFilesMiddleware = require('./middleware/source_files')
-var proxyMiddleware = require('./middleware/proxy')
-
-var log = require('./logger').create('web-server')
-
-var createCustomHandler = function (customFileHandlers, /* config.basePath */ basePath) {
+'use strict'
+
+const fs = require('graceful-fs')
+const http = require('http')
+const https = require('https')
+const path = require('path')
+const connect = require('connect')
+const Promise = require('bluebird')
+
+const common = require('./middleware/common')
+const runnerMiddleware = require('./middleware/runner')
+const stopperMiddleware = require('./middleware/stopper')
+const stripHostMiddleware = require('./middleware/strip_host')
+const karmaMiddleware = require('./middleware/karma')
+const sourceFilesMiddleware = require('./middleware/source_files')
+const proxyMiddleware = require('./middleware/proxy')
+
+const log = require('./logger').create('web-server')
+
+function createCustomHandler (customFileHandlers, config) {
   return function (request, response, next) {
-    for (var i = 0; i < customFileHandlers.length; i++) {
-      if (customFileHandlers[i].urlRegex.test(request.url)) {
-        return customFileHandlers[i].handler(request, response, 'fake/static', 'fake/adapter',
-          basePath, 'fake/root')
-      }
-    }
-
-    return next()
+    const handler = customFileHandlers.find((handler) => handler.urlRegex.test(request.url))
+    return handler
+      ? handler.handler(request, response, 'fake/static', 'fake/adapter', config.basePath, 'fake/root')
+      : next()
   }
 }
 
-createCustomHandler.$inject = ['customFileHandlers', 'config.basePath']
+createCustomHandler.$inject = ['customFileHandlers', 'config']
 
-var createWebServer = function (injector, emitter, fileList) {
-  var config = injector.get('config')
+function createWebServer (injector, emitter, fileList) {
+  const config = injector.get('config')
   common.initializeMimeTypes(config)
-  var serveStaticFile = common.createServeFile(fs, path.normalize(path.join(__dirname, '/../static')), config)
-  var serveFile = common.createServeFile(fs, null, config)
-  var filesPromise = new common.PromiseContainer()
+  const serveStaticFile = common.createServeFile(fs, path.normalize(path.join(__dirname, '/../static')), config)
+  const serveFile = common.createServeFile(fs, null, config)
+  const filesPromise = new common.PromiseContainer()
 
   // Set an empty list of files to avoid race issues with
   // file_list_modified not having been emitted yet
   filesPromise.set(Promise.resolve(fileList.files))
 
-  emitter.on('file_list_modified', function (files) {
-    filesPromise.set(Promise.resolve(files))
-  })
+  emitter.on('file_list_modified', (files) => filesPromise.set(Promise.resolve(files)))
 
   // locals for webserver module
   // NOTE(vojta): figure out how to do this with DI
@@ -53,15 +49,13 @@ var createWebServer = function (injector, emitter, fileList) {
     filesPromise: ['value', filesPromise]
   }])
 
-  var proxyMiddlewareInstance = injector.invoke(proxyMiddleware.create)
+  const proxyMiddlewareInstance = injector.invoke(proxyMiddleware.create)
 
   log.debug('Instantiating middleware')
-  var handler = connect()
+  const handler = connect()
 
   if (config.beforeMiddleware) {
-    config.beforeMiddleware.forEach(function (middleware) {
-      handler.use(injector.get('middleware:' + middleware))
-    })
+    config.beforeMiddleware.forEach((middleware) => handler.use(injector.get('middleware:' + middleware)))
   }
 
   handler.use(injector.invoke(runnerMiddleware.create))
@@ -76,17 +70,13 @@ var createWebServer = function (injector, emitter, fileList) {
   handler.use(injector.invoke(createCustomHandler))
 
   if (config.middleware) {
-    config.middleware.forEach(function (middleware) {
-      handler.use(injector.get('middleware:' + middleware))
-    })
+    config.middleware.forEach((middleware) => handler.use(injector.get('middleware:' + middleware)))
   }
 
-  handler.use(function (request, response) {
-    common.serve404(response, request.url)
-  })
+  handler.use((request, response) => common.serve404(response, request.url))
 
-  var serverClass = http
-  var serverArguments = [handler]
+  let serverClass = http
+  const serverArguments = [handler]
 
   if (config.protocol === 'https:') {
     serverClass = https
@@ -97,7 +87,7 @@ var createWebServer = function (injector, emitter, fileList) {
     serverClass = config.httpModule
   }
 
-  var server = serverClass.createServer.apply(null, serverArguments)
+  const server = serverClass.createServer.apply(null, serverArguments)
 
   server.on('upgrade', function (req, socket, head) {
     log.debug('upgrade %s', req.url)
@@ -107,5 +97,5 @@ var createWebServer = function (injector, emitter, fileList) {
   return server
 }
 
-// PUBLIC API
-exports.create = createWebServer
+createWebServer.$inject = ['injector', 'emitter', 'fileList']
+exports.createWebServer = createWebServer