To develop and test the code in this book, I used several versions of commonly available software, including browsers and Node.js, as well as some other packages.
For this second edition, my main machine runs the Tumbleweed rolling release of OpenSUSE Linux, from https://www.opensuse.org/#Tumbleweed, currently including kernel 5.3.5. (The rolling term implies that the software is updated on a continuous basis, to keep getting the latest versions of all packages.) I've also tested portions of the code of this book on different Windows 7 and Windows 10 machines.
As to browsers, I usually work with Chrome, from https://www.google.com/chrome/browser/, and at the current time, I'm up to version 78. I also use Firefox, from https://www.mozilla.org/en-US/firefox/, and I got version 72 in my machine. I have also run code using the online JSFiddle environment, at https://jsfiddle.net/.
On the server side, I use Node.js, from https://nodejs.org/, currently at version 13.6.
For transpilation, I used Babel, from https://babeljs.io/: the current version of the babel-cli package is 7.7.7.
For testing, I went with Jasmine, from https://jasmine.github.io/, and the latest version in my machine is 3.5.0.