diff --git a/.travis.yml b/.travis.yml
index dd78643..f6d1d55 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,8 @@
 language: node_js
 node_js:
   - "0.10"
+before_script:
+  - "sudo apt-get install -y chromium-browser"
 notifications:
   email:
     on_success: never
diff --git a/karma.conf.js b/karma.conf.js
new file mode 100644
index 0000000..821066a
--- /dev/null
+++ b/karma.conf.js
@@ -0,0 +1,73 @@
+"use strict";
+
+process.env.CHROME_BIN = "chromium-browser";
+
+module.exports = function(config) {
+  config.set({
+
+    // base path that will be used to resolve all patterns (eg. files, exclude)
+    basePath: "",
+
+
+    // frameworks to use
+    // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
+    frameworks: ["mocha", "browserify"],
+
+
+    // list of files / patterns to load in the browser
+    files: [
+      "test.js"
+    ],
+
+
+    // preprocess matching files before serving them to the browser
+    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
+    preprocessors: {
+      "test.js": ["browserify"],
+    },
+
+
+    // list of files to exclude
+    exclude: [
+    ],
+
+
+    // test results reporter to use
+    // possible values: "dots", "progress"
+    // available reporters: https://npmjs.org/browse/keyword/karma-reporter
+    reporters: ["mocha"],
+
+
+    // web server port
+    port: 9876,
+
+
+    // enable / disable colors in the output (reporters and logs)
+    colors: true,
+
+
+    // level of logging
+    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
+    logLevel: config.LOG_INFO,
+
+
+    // enable / disable watching file and executing tests whenever any file changes
+    autoWatch: true,
+
+
+    // start these browsers
+    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
+    browsers: ["chromium_no_sandbox"],
+    customLaunchers: {
+      chromium_no_sandbox: {
+        base: "Chrome",
+        flags: ["--no-sandbox"],
+      },
+    },
+
+
+    // Continuous Integration mode
+    // if true, Karma captures browsers, runs the tests and exits
+    singleRun: false,
+  });
+};
diff --git a/lib/crypto.browser.js b/lib/crypto.browser.js
index 3c553ff..91f3c69 100644
--- a/lib/crypto.browser.js
+++ b/lib/crypto.browser.js
@@ -2,3 +2,11 @@
  * Browser version of the crypto for Bitmessage JS implementation.
  * @module bitmessage/lib/crypto.browser
  */
+
+"use strict";
+
+exports.sha512 = function(buf) {
+  return window.crypto.subtle.digest({name: "SHA-512"}, buf).then(function(arr) {
+    return new Buffer(new Uint8Array(arr));
+  });
+};
diff --git a/package.json b/package.json
index 0a88059..89cedd6 100644
--- a/package.json
+++ b/package.json
@@ -2,12 +2,13 @@
   "name": "bitmessage",
   "version": "0.0.0",
   "description": "JavaScript Bitmessage library",
-  "main": "./lib/index",
+  "main": "./lib/index.js",
   "browser": {
-    "./lib/crypto": "./lib/crypto.browser"
+    "./lib/crypto.js": "./lib/crypto.browser.js"
   },
   "scripts": {
-    "test": "mocha && jshint ."
+    "test": "mocha && xvfb-run -a karma start --single-run && jshint .",
+    "karma": "xvfb-run -a karma start"
   },
   "repository": {
     "type": "git",
@@ -28,6 +29,12 @@
   "devDependencies": {
     "chai": "*",
     "jshint": "*",
+    "karma": "^0.12.28",
+    "karma-browserify": "^1.0.1",
+    "karma-chrome-launcher": "^0.1.7",
+    "karma-cli": "~0.0.4",
+    "karma-mocha": "^0.1.10",
+    "karma-mocha-reporter": "^0.3.1",
     "mocha": "*"
   },
   "dependencies": {
diff --git a/test.js b/test.js
index 34d9898..2683bf3 100644
--- a/test.js
+++ b/test.js
@@ -3,10 +3,9 @@ var expect = require("chai").expect;
 var bmcrypto = require("./lib/crypto");
 
 describe("Bitmessage crypto", function() {
-  it("should calculate sha512 hash for both node and browserify", function(done) {
-    bmcrypto.sha512(new Buffer("test")).then(function(res) {
+  it("should calculate sha512 hash", function() {
+    return bmcrypto.sha512(new Buffer("test")).then(function(res) {
       expect(res.toString("hex")).to.equal("ee26b0dd4af7e749aa1a8ee3c10ae9923f618980772e473f8819a5d4940e0db27ac185f8a0e1d5f84f88bc887fd67b143732c304cc5fa9ad8e6f57f50028a8ff");
-      done();
     });
   });
 });