I’ve used the Google Closure Compiler for some JS13K projects, since it is so effective at producing small JavaScript code. At the time (a few years ago), there

I’ve used the Google Closure Compiler for some JS13K projects, since it is so effective at producing small JavaScript code. At the time (a few years ago), there were some rough edges trying to use the Closure Compiler without the Closure Library, but they weren’t major problems—in fact, there was only one thing I added to my project as a workaround: const goog = { define(name, value) { return value; } }; That was it. I used it to select between development and release versions of the project, because the release version had to fit in 13 KB (compressed).