Frontend System Design
System design content online is almost all backend — load balancers, databases, message queues. The frontend-specific version — rendering strategy, state at scale, performance, micro-frontends — is what a senior or staff frontend interview actually spends its system design round on, and it is rare to find taught well. This is that course.
26 lessons · 297 min total · free to read, no account needed
Rendering strategy
CSR, SSR, SSG, ISR and streaming — the actual trade-offs in TTFB, TTI, SEO and infrastructure cost, not just definitions.
State at scale
Why "put everything in global state" fails, server state vs. client state, and the caching/staleness problem that creates.
Performance at scale
The critical rendering path, code-splitting trade-offs, virtualization, and Core Web Vitals as the actual scoring rubric.
Architecture at scale
Micro-frontends and design systems — what they really cost a team, and when a well-organized monolith is the right call instead.
Taught as reasoning, not a checklist
Real system design has few universally correct answers — the skill being tested is whether you can name the trade-offs and argue for one under the constraints you were given. Every lesson here is built around that: what changes if traffic is huge, if the team is small, if SEO matters, if the data changes every second. The capstone lessons pose an actual “design X” prompt and walk through the reasoning a strong answer would use.
- Rendering, state, performance and architecture, covered as trade-offs with real conditions attached
- Diagrams for every architecture and data-flow, not walls of prose
- Capstone lessons that pose a real interview prompt and reason through it end to end
Prove it: Frontend System Design Certification
140 min, 55 questions, a certificate with a public link if you pass.
See the exam