An overview of an interesting new development over the past years -- many vendors, large and small, have been making their JavaScript-based technology stacks available on GitHub. What does that mean and how to evaluate this development? Find out in this session, which includes small code demos and tips and tricks. Did you know that over the past few years, large enterprises have been developing and open sourcing their JavaScript technology stacks? On GitHub, you'll find solutions by ING, Uber, PayPal, the Financial Times, Oracle, Microsoft, and many others. Some of these are software vendors, while others are in a variety of other industries. Each of them start from open source frameworks and libraries and all of them are interested in contributions. The session, with several live coding scenarios, focuses on something that's been going on below the surface, mostly unseen: large enterprises are using open source solutions in the JavaScript ecosystem (e.g., React, Vue, Knockout, Angular), developing their own internal tech stacks, and then pushing these stacks out to GitHub. Let's explore the advantages of these and see what can be done and how practical these developments are.