diff --git a/react-packager/src/AssetServer/__tests__/AssetServer-test.js b/react-packager/src/AssetServer/__tests__/AssetServer-test.js
index 95916c9e..54ef7012 100644
--- a/react-packager/src/AssetServer/__tests__/AssetServer-test.js
+++ b/react-packager/src/AssetServer/__tests__/AssetServer-test.js
@@ -8,22 +8,22 @@ jest
   .mock('crypto')
   .mock('fs');
 
-var Promise = require('promise');
+const Promise = require('promise');
 
-describe('AssetServer', function() {
-  var AssetServer;
-  var crypto;
-  var fs;
+describe('AssetServer', () => {
+  let AssetServer;
+  let crypto;
+  let fs;
 
-  beforeEach(function() {
+  beforeEach(() => {
     AssetServer = require('../');
     crypto = require('crypto');
     fs = require('fs');
   });
 
-  describe('assetServer.get', function() {
-    pit('should work for the simple case', function() {
-      var server = new AssetServer({
+  describe('assetServer.get', () => {
+    pit('should work for the simple case', () => {
+      const server = new AssetServer({
         projectRoots: ['/root'],
         assetExts: ['png'],
       });
@@ -40,15 +40,15 @@ describe('AssetServer', function() {
       return Promise.all([
         server.get('imgs/b.png'),
         server.get('imgs/b@1x.png'),
-      ]).then(function(resp) {
-        resp.forEach(function(data) {
-          expect(data).toBe('b image');
-        });
-      });
+      ]).then(resp =>
+        resp.forEach(data =>
+          expect(data).toBe('b image')
+        )
+      );
     });
 
-    pit('should work for the simple case with jpg', function() {
-      var server = new AssetServer({
+    pit('should work for the simple case with jpg', () => {
+      const server = new AssetServer({
         projectRoots: ['/root'],
         assetExts: ['png', 'jpg'],
       });
@@ -65,16 +65,16 @@ describe('AssetServer', function() {
       return Promise.all([
         server.get('imgs/b.jpg'),
         server.get('imgs/b.png'),
-      ]).then(function(data) {
+      ]).then(data =>
         expect(data).toEqual([
           'jpeg image',
           'png image',
-        ]);
-      });
+        ])
+      );
     });
 
-    pit('should pick the bigger one', function() {
-      var server = new AssetServer({
+    pit('should pick the bigger one', () => {
+      const server = new AssetServer({
         projectRoots: ['/root'],
         assetExts: ['png'],
       });
@@ -90,13 +90,13 @@ describe('AssetServer', function() {
         }
       });
 
-      return server.get('imgs/b@3x.png').then(function(data) {
-        expect(data).toBe('b4 image');
-      });
+      return server.get('imgs/b@3x.png').then(data =>
+        expect(data).toBe('b4 image')
+      );
     });
 
-    pit('should support multiple project roots', function() {
-      var server = new AssetServer({
+    pit('should support multiple project roots', () => {
+      const server = new AssetServer({
         projectRoots: ['/root', '/root2'],
         assetExts: ['png'],
       });
@@ -116,27 +116,23 @@ describe('AssetServer', function() {
         },
       });
 
-      return server.get('newImages/imgs/b.png').then(function(data) {
-        expect(data).toBe('b1 image');
-      });
+      return server.get('newImages/imgs/b.png').then(data =>
+        expect(data).toBe('b1 image')
+      );
     });
   });
 
-  describe('assetSerer.getAssetData', function() {
-    pit('should get assetData', function() {
-      var hash = {
+  describe('assetSerer.getAssetData', () => {
+    pit('should get assetData', () => {
+      const hash = {
         update: jest.genMockFn(),
         digest: jest.genMockFn(),
       };
 
-      hash.digest.mockImpl(function() {
-        return 'wow such hash';
-      });
-      crypto.createHash.mockImpl(function() {
-        return hash;
-      });
+      hash.digest.mockImpl(() => 'wow such hash');
+      crypto.createHash.mockImpl(() => hash);
 
-      var server = new AssetServer({
+      const server = new AssetServer({
         projectRoots: ['/root'],
         assetExts: ['png'],
       });
@@ -152,7 +148,7 @@ describe('AssetServer', function() {
         }
       });
 
-      return server.getAssetData('imgs/b.png').then(function(data) {
+      return server.getAssetData('imgs/b.png').then(data => {
         expect(hash.update.mock.calls.length).toBe(4);
         expect(data).toEqual({
           type: 'png',
@@ -163,20 +159,16 @@ describe('AssetServer', function() {
       });
     });
 
-    pit('should get assetData for non-png images', function() {
-      var hash = {
+    pit('should get assetData for non-png images', () => {
+      const hash = {
         update: jest.genMockFn(),
         digest: jest.genMockFn(),
       };
 
-      hash.digest.mockImpl(function() {
-        return 'wow such hash';
-      });
-      crypto.createHash.mockImpl(function() {
-        return hash;
-      });
+      hash.digest.mockImpl(() => 'wow such hash');
+      crypto.createHash.mockImpl(() => hash);
 
-      var server = new AssetServer({
+      const server = new AssetServer({
         projectRoots: ['/root'],
         assetExts: ['png', 'jpeg'],
       });
@@ -192,7 +184,7 @@ describe('AssetServer', function() {
         }
       });
 
-      return server.getAssetData('imgs/b.jpg').then(function(data) {
+      return server.getAssetData('imgs/b.jpg').then(data => {
         expect(hash.update.mock.calls.length).toBe(4);
         expect(data).toEqual({
           type: 'jpg',
diff --git a/react-packager/src/AssetServer/index.js b/react-packager/src/AssetServer/index.js
index 2cd365fd..f442f6b8 100644
--- a/react-packager/src/AssetServer/index.js
+++ b/react-packager/src/AssetServer/index.js
@@ -8,20 +8,20 @@
  */
 'use strict';
 
-var declareOpts = require('../lib/declareOpts');
-var getAssetDataFromName = require('../lib/getAssetDataFromName');
-var path = require('path');
-var Promise = require('promise');
-var fs = require('fs');
-var crypto = require('crypto');
+const Promise = require('promise');
 
-var stat = Promise.denodeify(fs.stat);
-var readDir = Promise.denodeify(fs.readdir);
-var readFile = Promise.denodeify(fs.readFile);
+const crypto = require('crypto');
+const declareOpts = require('../lib/declareOpts');
+const fs = require('fs');
+const getAssetDataFromName = require('../lib/getAssetDataFromName');
+const path = require('path');
 
-module.exports = AssetServer;
+const stat = Promise.denodeify(fs.stat);
+const readDir = Promise.denodeify(fs.readdir);
+const readFile = Promise.denodeify(fs.readFile);
 
-var validateOpts = declareOpts({
+
+const validateOpts = declareOpts({
   projectRoots: {
     type: 'array',
     required: true,
@@ -32,135 +32,136 @@ var validateOpts = declareOpts({
   },
 });
 
-function AssetServer(options) {
-  var opts = validateOpts(options);
-  this._roots = opts.projectRoots;
-  this._assetExts = opts.assetExts;
-}
+class AssetServer {
+  constructor(options) {
+    const opts = validateOpts(options);
+    this._roots = opts.projectRoots;
+    this._assetExts = opts.assetExts;
+  }
 
-/**
- * Given a request for an image by path. That could contain a resolution
- * postfix, we need to find that image (or the closest one to it's resolution)
- * in one of the project roots:
- *
- * 1. We first parse the directory of the asset
- * 2. We check to find a matching directory in one of the project roots
- * 3. We then build a map of all assets and their scales in this directory
- * 4. Then pick the closest resolution (rounding up) to the requested one
- */
-
-AssetServer.prototype._getAssetRecord = function(assetPath) {
-  var filename = path.basename(assetPath);
-
-  return findRoot(
-    this._roots,
-    path.dirname(assetPath)
-  ).then(function(dir) {
-    return Promise.all([
-      dir,
-      readDir(dir),
-    ]);
-  }).then(function(res) {
-    var dir = res[0];
-    var files = res[1];
-    var assetData = getAssetDataFromName(filename);
-
-    var map = buildAssetMap(dir, files);
-    var record = map[assetData.assetName];
-
-    if (!record) {
-      throw new Error('Asset not found');
-    }
-
-    return record;
-  });
-};
-
-AssetServer.prototype.get = function(assetPath) {
-  var assetData = getAssetDataFromName(assetPath);
-  return this._getAssetRecord(assetPath).then(function(record) {
-    for (var i = 0; i < record.scales.length; i++) {
-      if (record.scales[i] >= assetData.resolution) {
-        return readFile(record.files[i]);
+  get(assetPath) {
+    const assetData = getAssetDataFromName(assetPath);
+    return this._getAssetRecord(assetPath).then(record => {
+      for (let i = 0; i < record.scales.length; i++) {
+        if (record.scales[i] >= assetData.resolution) {
+          return readFile(record.files[i]);
+        }
       }
-    }
 
-    return readFile(record.files[record.files.length - 1]);
-  });
-};
+      return readFile(record.files[record.files.length - 1]);
+    });
+  }
 
-AssetServer.prototype.getAssetData = function(assetPath) {
-  var nameData = getAssetDataFromName(assetPath);
-  var data = {
-    name: nameData.name,
-    type: nameData.type,
-  };
+  getAssetData(assetPath) {
+    const nameData = getAssetDataFromName(assetPath);
+    const data = {
+      name: nameData.name,
+      type: nameData.type,
+    };
 
-  return this._getAssetRecord(assetPath).then(function(record) {
-    data.scales = record.scales;
+    return this._getAssetRecord(assetPath).then(record => {
+      data.scales = record.scales;
 
-    return Promise.all(
-      record.files.map(function(file) {
-        return stat(file);
+      return Promise.all(
+        record.files.map(file => stat(file))
+      );
+    }).then(stats => {
+      const hash = crypto.createHash('md5');
+
+      stats.forEach(fstat =>
+        hash.update(fstat.mtime.getTime().toString())
+      );
+
+      data.hash = hash.digest('hex');
+      return data;
+    });
+  }
+
+  /**
+   * Given a request for an image by path. That could contain a resolution
+   * postfix, we need to find that image (or the closest one to it's resolution)
+   * in one of the project roots:
+   *
+   * 1. We first parse the directory of the asset
+   * 2. We check to find a matching directory in one of the project roots
+   * 3. We then build a map of all assets and their scales in this directory
+   * 4. Then pick the closest resolution (rounding up) to the requested one
+   */
+  _getAssetRecord(assetPath) {
+    const filename = path.basename(assetPath);
+
+    return (
+      this._findRoot(
+        this._roots,
+        path.dirname(assetPath)
+      )
+      .then(dir => Promise.all([
+        dir,
+        readDir(dir),
+      ]))
+      .then(res => {
+        const dir = res[0];
+        const files = res[1];
+        const assetData = getAssetDataFromName(filename);
+
+        const map = this._buildAssetMap(dir, files);
+        const record = map[assetData.assetName];
+
+        if (!record) {
+          throw new Error('Asset not found');
+        }
+
+        return record;
       })
     );
-  }).then(function(stats) {
-    var hash = crypto.createHash('md5');
+  }
 
-    stats.forEach(function(fstat) {
-      hash.update(fstat.mtime.getTime().toString());
-    });
-
-    data.hash = hash.digest('hex');
-    return data;
-  });
-};
-
-function findRoot(roots, dir) {
-  return Promise.all(
-    roots.map(function(root) {
-      var absPath = path.join(root, dir);
-      return stat(absPath).then(function(fstat) {
-        return {path: absPath, isDirectory: fstat.isDirectory()};
-      }, function (err) {
-        return {path: absPath, isDirectory: false};
-      });
-    })
-  ).then(
-    function(stats) {
-      for (var i = 0; i < stats.length; i++) {
+  _findRoot(roots, dir) {
+    return Promise.all(
+      roots.map(root => {
+        const absPath = path.join(root, dir);
+        return stat(absPath).then(fstat => {
+          return {path: absPath, isDirectory: fstat.isDirectory()};
+        }, err => {
+          return {path: absPath, isDirectory: false};
+        });
+      })
+    ).then(stats => {
+      for (let i = 0; i < stats.length; i++) {
         if (stats[i].isDirectory) {
           return stats[i].path;
         }
       }
       throw new Error('Could not find any directories');
-    }
-  );
-}
+    });
+  }
 
-function buildAssetMap(dir, files) {
-  var assets = files.map(getAssetDataFromName);
-  var map = Object.create(null);
-  assets.forEach(function(asset, i) {
-    var file = files[i];
-    var record = map[asset.assetName];
-    if (!record) {
-      record = map[asset.assetName] = {
-        scales: [],
-        files: [],
-      };
-    }
-
-    var insertIndex;
-    var length = record.scales.length;
-    for (insertIndex = 0; insertIndex < length; insertIndex++) {
-      if (asset.resolution <  record.scales[insertIndex]) {
-        break;
+  _buildAssetMap(dir, files) {
+    const assets = files.map(getAssetDataFromName);
+    const map = Object.create(null);
+    assets.forEach(function(asset, i) {
+      const file = files[i];
+      let record = map[asset.assetName];
+      if (!record) {
+        record = map[asset.assetName] = {
+          scales: [],
+          files: [],
+        };
       }
-    }
-    record.scales.splice(insertIndex, 0, asset.resolution);
-    record.files.splice(insertIndex, 0, path.join(dir, file));
-  });
 
-  return map;
+      let insertIndex;
+      const length = record.scales.length;
+      for (insertIndex = 0; insertIndex < length; insertIndex++) {
+        if (asset.resolution <  record.scales[insertIndex]) {
+          break;
+        }
+      }
+      record.scales.splice(insertIndex, 0, asset.resolution);
+      record.files.splice(insertIndex, 0, path.join(dir, file));
+    });
+
+    return map;
+  }
 }
+
+module.exports = AssetServer;