Most programs you write use only a segment of the libraries you dep. Closure DCE is really, really good when it has type knowledge. Kills branches, inlines code

Most programs you write use only a segment of the libraries you dep. Closure DCE is really, really good when it has type knowledge. Kills branches, inlines code, etc. It blows anything else in the javascript ecosystem out of the water in that regard (which is important if you're using Closure libraries, because the Closure libraries are massive without DCE). That said, these days I wouldn't use Closure raw. The tooling is just awful, years out of date. ClojureScript doesn't have that issue though. It gets all the benefits without the crappy tooling.