Updated: Jun 30, 2020
It added quite a bit of new features and tried to improve other existing ones.
I wrote a fairly read article about it on Medium called "What is Deno and will it Replace Node?"
Truth be told, Deno is fairly new and it's hard to assess if it will actually end up gaining significant ground over Node, especially because there is no telling what will the latter do in order to adapt.
But with that being said, a lot of people have shown interest in Deno because of the features it brought to the table, such as native TypeScript support (this one being one of the most liked ones). This is why I was offered to write an introductory book into Deno by the folks at Apress.
The book will not be too big, it'll focus on Deno and TypeScript, since this is one of the major new features added into the runtime. But it'll cover everything in between, here is the ToC so you can get an idea of what's to come:
Chapter 1: Introduction
Covering the reasons why Deno was created, what new features and improvements it brings over Node.js, and some basic code samples.
Chapter 2: An intro to Typescript
The chapter will cover the basic concepts of TypeScript to make sure the reader understands the basics for the code samples that will follow.
Chapter 3: Living a secure life
A more in-depth chapter covering everything about the new security layer and code examples to showcase the feature.
Chapter 4: No more NPM
A detailed chapter covering how Deno intends to handle modules including several code examples showcasing the different features.
Chapter 5: Existing modules
Review of the standard library and some already existing ports from Node.js that can be used with Deno. All covered modules will have at least one code sample associated with them.
Chapter 6: Sample apps
The final chapter will cover a few practical projects to showcase how different types of applications can look like using Deno and how to structure them.
If you're interested in Deno and would like to know more about the book, feel free to leave your email down below, or just follow me on my social media (links down below), I'll be posting news about it pretty soon!