diff --git a/config/karma.conf.js b/config/karma.conf.js
index 3d221f4..cd99a33 100644
--- a/config/karma.conf.js
+++ b/config/karma.conf.js
@@ -57,7 +57,7 @@ module.exports = function(config) {
      * possible values: 'dots', 'progress'
      * available reporters: https://npmjs.org/browse/keyword/karma-reporter
      */
-    reporters: [ 'mocha', 'coverage' ],
+    reporters: [ 'mocha', 'coverage', 'remap-coverage' ],
 
     // web server port
     port: 9876,
diff --git a/config/webpack.test.js b/config/webpack.test.js
index 63cedcf..4c226f4 100644
--- a/config/webpack.test.js
+++ b/config/webpack.test.js
@@ -145,6 +145,26 @@ module.exports = function (options) {
           test: /\.html$/,
           use: ['raw-loader'],
           exclude: [helpers.root('src/index.html')]
+        },
+
+      /**
+         * Instruments JS files with Istanbul for subsequent code coverage reporting.
+         * Instrument only testing sources.
+         *
+         * See: https://github.com/deepsweet/istanbul-instrumenter-loader
+         */
+        {
+          enforce: 'post',
+          test: /\.(js|ts)$/,
+          loader: 'istanbul-instrumenter-loader',
+          query: {
+            esModules: true
+          },
+          include: helpers.root('src'),
+          exclude: [
+            /\.(e2e|spec)\.ts$/,
+            /node_modules/
+          ]
         }
       ]
     },
diff --git a/package.json b/package.json
index cce5f75..e5737d9 100644
--- a/package.json
+++ b/package.json
@@ -118,6 +118,7 @@
     "karma-chrome-launcher": "2.0.0",
     "karma-cli": "1.0.1",
     "karma-coverage": "1.1.1",
+    "karma-remap-coverage": "^0.1.4",
     "karma-htmlfile-reporter": "0.3.5",
     "karma-jasmine": "1.1.0",
     "karma-jasmine-html-reporter": "0.2.2",