Workspaces is a long-requested feature that gives NPM a set of features to manage multiple packages from within a singular, top-level root package. Driving the addition of this capability is a desire to manage multiple packages that may or may not be used together.
Also in version 7.0.0, NPM automatically installs peer dependencies. Previously, developers had to manage these on their own. A new peer dependency algorithm ensures that a validly matching peer dependency is found at or above the peer-dependent location in the node_modules tree. Note that automatic installation of peer dependencies could potentially break certain workflows.