Frontend system design in 5 days
A week to prep for the system-design round nobody practices.
The round that most frontend candidates underprepare for: not "load balancer vs database," but rendering strategy, state at scale, perf budgets, and the component architecture that makes a design feel senior. One lesson a day for the week before the round.
9 items · ~3h of focused work
Day 1 · Framework
Day 2 · Rendering
- CSR, SSR and SSG: The Real Trade-offsClient-side, server-side and static rendering compared honestly: what each actually costs in TTFB, TTI, SEO and infrastructure, and why there is no universal winner.12 min
- Streaming SSR and SuspenseWhy waiting for the slowest data on a page before sending any HTML is wasteful, and how streaming SSR with Suspense sends the fast parts first.11 min
Day 3 · State
- Local, Lifted, and Global StateWhy state should default to the smallest scope that works, what lifting state actually costs, and why 'put everything in global state' fails as an app grows.10 min
- Server State vs. Client StateWhy data that lives on a server is a fundamentally different problem from UI state — caching, staleness and revalidation — and why treating them the same causes bugs.12 min
Day 4 · Perf
- Core Web Vitals, Images, and FontsLCP, INP and CLS as the actual scoring rubric behind 'is this page fast,' and the concrete image and font loading strategies that move each metric.12 min
- Code-Splitting and Bundle BudgetsWhy one giant bundle is the wrong default, how route- and component-level splitting trade upfront load for later waterfalls, and setting a real budget.11 min
Day 5 · Rehearsal
- Worked Scenario: Design a Social Media FeedA full worked answer to a classic interview prompt — rendering strategy, an infinite-scroll data model, virtualization, and optimistic interactions, with the trade-offs named.14 min
- Worked Scenario: Design an Image-Heavy E-Commerce PLPA full worked answer for a product listing page: rendering strategy for SEO and freshness, image loading strategy against Core Web Vitals, and filter-driven state.13 min