Front-End

Front-end engineering is the discipline of building what runs in the browser (and, increasingly, on the device): the layer users actually touch. It is its own stack — build tooling, component architecture, performance budgets, network behavior, accessibility, monitoring — separate from anything that runs on a server.

The material is organized by the questions you ask in practice:

• What do I need to know before I can build anything? — foundations
• How do I actually build the UI? — building UI
• How do I keep what I ship good? — quality
• How do I run it after it ships? — operations

Topics

Foundations

The non-negotiable groundwork — tooling, structure, and what the browser is actually doing.

• Engineering — Build tools, package management, monorepos, CI/CD for frontend.
• Architecture — Component design, state management, patterns, micro-frontends.
• Browser & Network — Browser internals, HTTP, security, storage — what is happening below your framework.

Building UI

Day-to-day work — laying things out, talking to APIs, using framework features.

• Responsive & Adaptive UI — Breakpoints, layout primitives, cross-platform patterns.
• Frameworks — Framework-specific engineering guides — Flutter, React Native, cross-platform.
• API Integration — REST, GraphQL, auth, error handling, caching, optimistic updates.
• Advanced Features — Web Components, Proxy, Observers, Workers, and advanced native APIs.

Quality

Making sure what you ship is fast, correct, and usable by everyone.

• Testing — Test strategy, unit, component, E2E, mobile testing.
• Performance — Loading, rendering, code optimization, Core Web Vitals.
• Accessibility — WCAG standards, ARIA, keyboard navigation, testing.

Operations

Knowing what your front-end is doing in real users' browsers, and diagnosing it when it misbehaves.

• Monitoring — Error tracking, RUM, observability tools.
• Troubleshooting — Common problems diagnosis and solutions.

Scope and Boundaries