Configuration :

1. Set NODE_ENV variable as 'production' to avoid installation of dev dependencies
   export NODE_ENV=production

Build essentials :

1. npm clean
    Removes current node_modules/ & package-lock.json
2. npm install
    Installs all packages listed in package.json
3. npm start
    Runs the server
4. npm test
    Executes the test cases

Caution: Paytm, Twilio, Google APIs are not enabled.

Flow Diagram (Transit):