What problem does it solve? Jac developers building client-side UIs need to consume third-party npm libraries and manage DOM refs, but the syntax differs from plain JavaScript. This Skill documents how to declare npm packages in jac.toml, import them in .jac files, and use Ref[T] fields, ref forwarding, and React hooks correctly. ## Core Features & Use Cases - npm Package Declaration: Add regular and dev dependencies under [dependencies.npm] in jac.toml, or patch it automatically with jac install --npm. - Import Syntax: Use double-quoted package names with named imports for libraries like recharts, lucide-react, radix-ui, and sonner. - Refs and Ref Forwarding: Declare Ref[T] fields instead of useRef, and forward refs through a trailing Ref parameter so components work as radix asChild trigger children. - React Hooks: Import useCallback, useMemo, useContext, and createContext directly from react alongside Jac sugar like has and can with entry. - Use Case: When adding a chart to a Jac app, declare recharts in jac.toml, run jac install, import ResponsiveContainer and LineChart, and wire a Ref[HTMLInputElement] for any focusable inputs. ## Quick Start Add the recharts npm package to my Jac project and show me how to import and use a LineChart component in a client .jac file.
