Yarn workspace

Yarn 1.0以降似選択できるアーキテクチャ

workspaceごとにpackage.json（dipendency）を持つ

workspaceを相互リンクできる

プロジェクトの依存関係はすべてインストール

それぞれのworkspaceでは自身の指定したファイルが配布される

Requiring workspace-a from a file located in workspace-b will now use the exact code currently located inside your project rather than what is published on npm, and the cross-env package has been correctly deduped and put at the root of your project to be used by both workspace-a and workspace-b.

単一のlockfile

Yarn’s workspaces are the low-level primitives that tools like Lerna can (and do!) use. They will never try to support the high-level feature that Lerna offers, but by implementing the core logic of the resolution and linking steps inside Yarn itself we hope to enable new usages and improve performance.