Transform optional chaining operators into a series of nil checks

@babel/plugin-proposal-optional-chaining

This plugin transforms static class properties as well as properties declared with the property initializer syntax

@babel/plugin-proposal-class-properties

A collection of essential TypeScript types

Uploading report to Codecov: https://codecov.io

Binary wrapper for Flow - A static type checker for JavaScript

FantasyLand compliant (monadic) alternative to Promises

Rollup plugin to trim trailing spaces, compact empty lines, and normalize line endings

JavaScript parser, mangler/compressor and beautifier toolkit for ES6+