Load Babel Presets Faster

This package flattens and dedups presets to make Babel load faster.

The transformations in a Babel preset are independent packages. Although these packages share many of the same dependencies, they all bring along their own node_modules. For this reason, a large preset like es2015 can be horribly bloated, taking a looooong time to install and to load.

Because the package has no dependencies, it installs quickly:

npm install babel-fast-presets

Use the flat presets in .babelrc:

{
  presets: ["babel-fast-presets/es2015-stage1"]
}

Which is the same as:

{
  presets: ["es2015","stage1"]
}

React

The React preset is pretty fast to load, so just use it normally:

{
  presets: ["babel-fast-presets/es2015-stage1", "react"]
}

Speedup

I get a ~73% reduction in loading time.

With flat presets:

$ babel --presets babel-fast-presets/es2015-stage1 examples/foo.js
1.27s user 0.11s system 104% cpu 1.314 total

Old presets:

$ time babel --presets es2015,stage-1 examples/foo.js
4.80s user 0.40s system 101% cpu 5.100 total

Enjoy~