Came to say this. I actually find QuickJS pretty easy to understand and modify, in part because everything is one file and it's easy to search, using vim's `#` and `*` keys, for example.

When working on projects by myself, I like putting everything in one big file too. Trying to find the "right" place for something is some unnecessary overhead, not to mention the navigation cost. It's a different story when a team is involved though.