webapplog [tech blog] Book author Azat Mardan writes about apps, startups and technology Usually good things don’t stay the same, so our tutorial on building a JSON REST API server with Node.js and MongoDB using Mongoskin and Express.js, and testing it with Mocha and Superagent, has became a bit outdated with the new Express.js 4 version release. Here’s a brand new, revisited tutorial for Express.