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Advanced integration scenarios between a NestJS API and a React client: BFF boundaries, cookie-based auth, CORS with credentials, DTO validation, and structured error mapping for forms and global UI.
Advanced full-path scenarios connecting React UI, Next.js App Router boundaries, and Node.js APIs across authentication, caching, streaming, uploads, and failure handling.
App Router boundaries, typing strategies, server data fetching, edge/runtime trade-offs, and production analytics concerns.
DOM interaction patterns, hooks rules, controlled components, list rendering, and avoiding common footguns.
Effects, memoization, context, lists, and common event/state patterns. Includes single-select and multi-select items.
Components, JSX, props, state basics, and event handling. Mix of single-answer and multiple-answer items; multi-select questions ask you to select every correct statement.
Concurrent features, transitions, suspense data, performance traps, and composition at scale. Demanding single- and multi-select items.
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