Shared UI Library Contract

Purpose

Use this skill to audit or design Angular shared UI and component libraries in Nx monorepos.

A shared UI library must behave as a reusable contract, not as a shortcut for app-specific logic. It should expose presentational components, stable APIs, projected content slots, styling conventions, and low-level composition primitives without leaking feature, domain, data-access, store, router, or backend concerns.

The core rule is simple:

Shared UI receives data and emits events.
Feature libraries decide what the data means.
Data-access libraries fetch and persist data.
Domain libraries own business concepts.

When to Use