Roadmap
What comes after week 4 — and the interview questions each topic unlocks
🚀 Path to Senior
TypeScript
Weeks 5-6, immediately after this trackWhy: Every serious React codebase at 2-3+ yrs experience is TS. It's the single highest-leverage thing you're missing after this track.
Learn: TS fundamentals → typing props/state/hooks → generics → migrate one of your projects to TS
Advanced Testing
Weeks 7-8Why: Confident PRs and code review credibility come from knowing what and how to test, not just RTL syntax.
Learn: Testing pyramid, mocking strategies (MSW), integration vs unit trade-offs, visual regression basics
System Design (Frontend)
Weeks 9-10Why: Interviews at 3-4 yr level test component architecture and scaling decisions, not just syntax.
Learn: Component API design, state colocation vs global state, micro-frontends overview, design systems
Performance at Scale
Weeks 9-10, alongside system designWhy: Juniors optimize a component; seniors reason about the whole app's render/network budget.
Learn: React Profiler workflows, virtualization (react-window), image/bundle optimization, Core Web Vitals
GraphQL
Weeks 11-12 (optional, job-dependent)Why: Common in mid-large product companies as an alternative to REST.
Learn: Apollo Client or urql basics, queries/mutations, caching model
Monorepos & Build Tooling
Weeks 11-12Why: Senior devs are expected to reason about the build, not just the app.
Learn: Turborepo/Nx basics, understanding Vite/webpack config, module federation overview
Open Source / Code Review Reps
Ongoing, start as soon as Week 3 projects existWhy: This is what compresses '4 weeks of tutorials' into 'reads like 3 years of experience' — there's no shortcut except reps.
Learn: Contribute to 2-3 real OSS repos; do code review on others' PRs; get your own PRs reviewed critically
🎯 Interview Prep — React Developer Mastery
Closures & 'this'▼
Typical questions: 'What's a closure, give an example'; 'What does this refer to in an arrow function vs regular function?'
What they're really checking: Whether you understand JS at a level below React, not just React syntax
Async JS / Promises▼
Typical questions: 'Explain the event loop'; 'Difference between Promise.all and Promise.allSettled'
What they're really checking: Debugging ability — async bugs are the most common real-world React bugs
useState vs useReducer▼
Typical questions: 'When would you use useReducer over useState?'
What they're really checking: Whether you can reason about state complexity, not just memorize hook APIs
useEffect▼
Typical questions: 'What's a stale closure bug and how do you fix it?'; 'Why does this effect run twice?'
What they're really checking: Depth — this is the #1 hook people use wrong; strong answers here signal real experience
Context API vs Redux▼
Typical questions: 'When would you NOT use Redux?'
What they're really checking: Judgment about tool selection and avoiding overengineering
Component Patterns (HOC/compound)▼
Typical questions: 'Refactor this prop-drilling example'; 'What's a compound component?'
What they're really checking: Whether you've built anything beyond tutorial-scale apps
Performance (memo/useMemo/useCallback)▼
Typical questions: 'When does useMemo NOT help?'; 'How do you find unnecessary re-renders?'
What they're really checking: Whether you optimize based on profiling data or cargo-cult memoization everywhere
Testing▼
Typical questions: 'How do you test a component that calls an API?'; 'Unit vs integration test here?'
What they're really checking: Production-readiness and whether you ship confidently
React Router / Protected Routes▼
Typical questions: 'How do you handle auth redirects?'
What they're really checking: Whether you've handled real app auth flows, not just static pages
Next.js / SSR vs CSR▼
Typical questions: 'When would you choose SSR over CSR?'
What they're really checking: Awareness of rendering strategies — increasingly expected even for 'React' roles