Via a simple parameter while starting Karma, we can achieve testing nirvana, as follows:

./node_modules/karma/bin/karma start karma.conf.js --auto-watch --no-single-run

Try it by yourself; run this command, change a file, and see the tests running automatically—like magic.

Once again, we don't want to remember these complicated commands, so let's add another script to the package.json file:

"scripts": {
  "test": "./node_modules/karma/bin/karma start karma.conf.js",
  "watch-test": "./node_modules/karma/bin/karma start karma.conf.js --auto-watch --no-single-run",
  "dev": "webpack-dev-server"
},

We can run it through the following command:

npm run watch-test

To achieve development nirvana, we are also just a parameter away.

While starting the development server, add the following to the package.json file:

./node_modules/.bin/webpack-dev-server --inline –hot

Once again, try it on your browser; change a file in the text editor and the browser should refresh.

You are also encouraged to update the package.json file with these new parameters so that running npm run dev gets you the goodness of "live reload".