Reuse

This skill sets the order for building anything new. The project's own parts come first, then a maintained library or a platform feature. Custom code comes last.

A duplicate is a finding

A new component, style or icon that duplicates one the project already has is a finding. Adding a primitive to the shared package and then using it is not. A project with no shared package is judged on the libraries it already depends on.

Cutting what nobody asked for belongs to restraint. Copying an outside app belongs to match.

The project's parts come first

Search the shared component package, the icon set and the tokens before writing UI. Name what you found. A raw <input> beside the project's Input is reuse-house-component-first.

Shipped components stay as shipped

Use a component's variants and data-* attributes. Restyling it with a local className is reuse-no-local-restyle.

One style per kind of thing