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README.md

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+# Now that `babel-preset-env` has stabilized, it has been [moved into the main Babel mono-repo](https://github.com/babel/babel/tree/master/packages/babel-preset-env) and this repo has been archived.
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+The move makes it much easier to release and develop in sync with the rest of Babel!
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+This repo will be made read-only, as all of the issues/labels have been moved over as well. Please report any bugs and open pull requests over on the [main mono-repo](https://github.com/babel/babel).
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 # babel-preset-env [![npm](https://img.shields.io/npm/v/babel-preset-env.svg)](https://www.npmjs.com/package/babel-preset-env) [![travis](https://img.shields.io/travis/babel/babel-preset-env/master.svg)](https://travis-ci.org/babel/babel-preset-env) [![npm-downloads](https://img.shields.io/npm/dm/babel-preset-env.svg)](https://www.npmjs.com/package/babel-preset-env) [![codecov](https://img.shields.io/codecov/c/github/babel/babel-preset-env/master.svg?maxAge=43200)](https://codecov.io/github/babel/babel-preset-env)
 
 > A Babel preset that compiles [ES2015+](https://github.com/tc39/proposals/blob/master/finished-proposals.md) down to ES5 by automatically determining the Babel plugins and polyfills you need based on your targeted browser or runtime environments.