Why is Babel a monorepo?

The tool for managing the monorepo in Babel has been extracted out as Lerna

Juggling a multimodule project over multiple repos is like trying to teach a newborn baby how to ride a bike.

Babel follows a monorepo approach, all officially maintained modules are in the same repo.

This is quite taboo but let's look at the pros and cons:

Pros:

Single lint, build, test and release process.
Easy to coordinate changes across modules.
Single place to report issues.
Easier to setup a development environment.
Tests across modules are run together which finds bugs that touch multiple modules easier.

Cons:

Codebase looks more intimidating.
Repo is bigger in size.
Can't npm install modules directly from GitHub
???

This is dumb! Nobody in open source does this!

React, Meteor, and Ember, among others, do this.

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