Yarn 3 requires Node ≥ 12.13.0; Node.js 20 satisfies this. Yarn 3 ships with workspace protocol (`workspace:*` ranges), patch protocol for in-place patching, and PnP mode. Use Corepack (`corepack enable`) to manage Yarn version per project without a global install. Yarn 4 is the current stable — upgrade with `yarn set version stable`.