The first stage was a phone screen with a developer. There were one or two questions about background, then on to technical questions about JavaScript.

The questions were mostly low-level, focusing on how the language and interpreter work. They covered topics like number precision, primitive types, and character encoding, rather than actually building software with JavaScript.

That part was about 30 minutes long. After that, we switched to a screenshare and did a JavaScript coding exercise. The exercise wasn't difficult; it dealt with array handling, but I was a bit rusty and made a couple of mistakes.

I didn't progress to the second stage, which was fair enough. The first part of the interview was tougher because almost all of the questions were things you either know or you don't, rather than things you can puzzle out. The second part was more familiar.

Many implementation details about how JavaScript works.