githubr1

Fair enough you'd want a like-for-like comparison. Even without changing the default configuration, upgrading the JS packages would improve their speed somewhat.

Unfortunately I am not aware of a large public ES codebase to test against. Most projects use Typescript as you mentioned. You could grab the ES bundle made by several projects and test against that, but that also wouldn't be a fair comparison.

The results in https://user-images.githubusercontent.com/406394/74600139-d1... are very informative. It matches my expectations.

I've been studying the Go code in esbuild - very clean and extensible. I think this project has a lot of potential. Thanks for sharing it with the world.

Thanks - I never thought to look in the parser for AST optimization.

By the way, it doesn't affect timings by more than 20%, but that repo has locked in rather old versions of rollup, terser, and other packages. You can disable tree shaking in rollup with --no-treeshake and still get comparable bundle sizes after using terser. That would save 3 seconds. There's no tree shaking opportunity in re-exporting all the symbols from the same library 10 times - all code must be retained. Using terser({compress: false}) would save an additional 17 seconds at the expense of making the final bundle 3% larger - 6.01mb total. Mind you even with upgraded packages and these config tweaks rollup+terser would still be 30x slower than esbuild - compiled languages will always win in speed.

Bundling and minifying a real app rather than a library might yield more interesting bundle size numbers due to dead code elimination. Providing gzip sizes would be interesting too - they aren't always proportional to the original ungzipped sizes.

constexpr - Cool project!

For those of us with slow internet connections please change your Makefile to use a shallow clone:

``` github/three: mkdir -p github git clone --depth 1 https://github.com/mrdoob/three.js.git github/three -b r108 cd github/three && git checkout r108 ```

This would save a couple of gigs and hours in download.

Just skimming your code I see variable mangling but no AST optimizations, is that correct? Which is odd because you show similar output sizes to the JS bundlers.