Frontend Engineering · 300-level

Frontend Engineering: Production User Interfaces

A staff-level deep dive into shipping frontend that survives production: rendering models, component and state architecture, Core Web Vitals, accessibility, design systems, data fetching, testing, and deploy/DX — each taught as a mechanism with its cost, failure mode, and guardrail.

FEN-3013 creditselectiveno prerequisites
What's inside

Sections & lessons

01

Rendering models

  • Choosing a rendering model per route: CSR, SSR, SSGconcept40 min
  • Hydration and why it, not first paint, governs interactivityconcept40 min
  • Streaming SSR and Suspense boundariesconcept35 min
  • React Server Components and the client boundaryconcept45 min
02

Component architecture and state

  • Composition over configuration: component APIs that scaleconcept40 min
  • State colocation and lifting: where state actually livesconcept40 min
  • Server state vs client state: stop putting fetched data in useStateconcept45 min
  • Global state without the re-render taxconcept40 min
  • Forms: controlled, uncontrolled, and validation at the boundaryconcept40 min
03

Performance and Core Web Vitals

  • The three Core Web Vitals and what moves eachconcept40 min
  • The JavaScript bundle: splitting, lazy loading, and the cost of shipping JSconcept40 min
  • Images and fonts: the biggest LCP leversconcept40 min
  • Measuring in the field: lab vs RUM, p75, and the tailconcept35 min
04

Accessibility

  • Semantic HTML first: the accessibility tree you get for freeconcept40 min
  • Keyboard operability and focus managementconcept40 min
  • ARIA and screen readers: when native semantics run outconcept40 min
  • Testing accessibility: automated, manual, and the coverage gapconcept35 min
05

Design systems and CSS architecture

  • Design tokens and themingconcept40 min
  • CSS architecture: utility, modules, and CSS-in-JS by costconcept40 min
  • Responsive design and component libraries: build vs buyconcept35 min
06

Data fetching, caching, and mutations

  • The client cache: query keys, staleness, and revalidationconcept40 min
  • Loading and error states as first-class UIconcept35 min
  • Mutations and optimistic updatesconcept40 min
  • Race conditions, cancellation, and out-of-order responsesconcept40 min
07

Testing and quality

  • The testing pyramid and testing-library philosophyconcept40 min
  • Component tests, e2e, and visual regressionconcept40 min
  • Avoiding flaky tests and keeping the suite trustedconcept35 min
08

Build, deploy, and developer experience

  • Bundlers and end-to-end type safetyconcept40 min
  • CI, preview deploys, and the deployment pipelineconcept35 min
  • Feature flags and frontend error monitoringconcept40 min

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