Lerna

Lerna is a management tool used to manage JavaScript projects that contain multiple packages.

Splitting a large code repository into multiple independent software packages is very useful for code sharing. However, if certain changes cross multiple code repositories, it will become cumbersome and difficult to track, and testing across multiple code repositories will quickly become very complex.

To address these (and many other) issues, some projects will split the code repository into multiple packages and store each package in a separate code repository. However, projects such as Babel, React, Angular, Ember, Meteor, Jest, and many others contain multiple software packages and are developed in a single code repository.

Lerna is a tool that optimizes the workflow of managing multiple package code repositories using Git and npm