Ironically - he doesn't it's kind of the whole flaw in the series.

How is JavaScript a minefield? Well, JavaScript has all sorts of pitfalls lurking for the developer. Each pitfall is like a mine in the minefield, silently waiting for you to accidentally step on it. Just like the minefield, JavaScript’s mines are hidden in plain sight. Entire books have been written about all the mines present in JavaScript. Maybe I’ll get into what some of those are in future blog posts.

So then he goes into why Typescript/Coffeescript/Dart aren't the answer to the "Javascript minefield" though he doesn't actually describe the mine's he's trying to avoid. He's not even bothering to setup a strawman to knock down. Its kind of hard for any tool to solve an undefined problem.