Frontend / Fullstack Interview Prep (Demo)

React internals: reconciliation, fiber, render vs commit, hooks rules, useTransition, useDeferredValue, useSyncExternalStore

Depth bar at senior level: explain "why" and "what trade-offs", not just the API name.

0%·Frontend Internals & Modern React/Next.js·~2h

Start

Program Completed0%

~44.5h remaining

Program Completed

~44.5h remaining

All Sections

React internals: reconciliation, fiber, render vs commit, hooks rules, useTransition, useDeferredValue, useSyncExternalStore

~2h

RSC + Next.js App Router: server vs client boundary, server actions, Suspense streaming, 4 cache layers, partial prerendering

~2h

State & data: local vs URL vs server state, TanStack Query mental model (stale-while-revalidate, mutations + invalidation), Zustand/Jotai vs Redux

~2h

Performance: Core Web Vitals (INP replaced FID), bundle splitting, hydration cost, memoization trade-offs, virtualization, image strategy

~2h

Modern CSS: cascade layers, container queries, :has(), subgrid, logical properties, scroll-driven animations, new color spaces, design tokens trade-off

~2h

TypeScript advanced: conditional types, infer, template literal types, branded types, as const, discriminated unions for state machines

~2h

Practice project: rebuild infinite-scroll feed 3 ways — RSC + server actions / TanStack Query / SSR + REST. Articulate trade-offs.

~4h

Design: news feed (Twitter/X) — pagination, real-time, optimistic updates

~1h

Design: autocomplete / typeahead — debouncing, ranking, caching, race conditions

~1h

Design: collaborative doc (Google Docs lite) — CRDTs vs OT at high level, presence

~1h

Design: photo gallery (Pinterest) — virtualization, image loading, masonry layout

~1h

Design: video player (YouTube) — adaptive bitrate, buffering, accessibility

~1h

Design: chat app — WebSocket/SSE, message ordering, offline queue

~1h

Design: real-time stock/crypto dashboard — leverage DeFi background here

~1h

Hash map + array manipulation (5–8 problems)

~2h

Two pointers / sliding window (5–8 problems)

~2h

BFS/DFS on trees and graphs (5–8 problems)

~2h

Heap / priority queue: top-K, merge-K problems

~2h

Dynamic programming: 1D + 2D canonical handful

~2h

Frontend utilities from scratch: debounce, throttle, Promise.all, EventEmitter, deep-clone, curry, memoize-with-TTL, retry-with-backoff

~3h

SOLID — frontend examples: single responsibility for hooks, dependency inversion via context

~1h

Composition over inheritance — compound components, render props, custom hooks

~1h

State machines (XState) vs ad-hoc booleans — when each fits

~1h

Domain-driven design — bounded contexts, anti-corruption layers (relevant for fullstack questions)

~1h

Testing strategy — the testing trophy (Kent Dodds), why integration > unit for UI, what to mock

~1h

Mock: frontend coding (Pramp / Hellointerview / friend — record yourself)

~2h

Mock: system design

~2h

Mock: behavioral

~1h

Prep 8 STAR stories: shipping under pressure, tech disagreement, mentoring, scope cut, production incident, ambiguous requirements, cross-team conflict, biggest mistake

~2h

Company research: engineering blog, public stack, use the product as a power user

~1h

Prepare 5 sharp questions for the interviewer

~30m