Hi, member of the TypeScript team here. A big reason for the file size increase seems to be the inclusion of an AMD module loader and AMD prologues themselves.

Hi, member of the TypeScript team here. A big reason for the file size increase seems to be the inclusion of an AMD module loader and AMD prologues themselves. By targeting CommonJS and using Browserify, you see a nice decrease. I've sent out a pull request since finding this. https://github.com/samccone/The-cost-of-transpiling-es2015-in-2016/pull/18 https://github.com/samccone/The-cost-of-transpiling-es2015-i...