Frontend Index v2.0
A living index of frontend engineering

Understand modern
frontend development

A visual reference system for modern frontend engineering — frameworks, tooling, architecture, and the production systems that ship the modern web. Click anything to go deep.

LIVE · ecosystem graph
01 · Roadmap

From the network up. The full progression.

Frontend isn't a stack — it's a sequence of layers, each built on what came before. Click any layer to open the full entry. Visited layers are remembered.

02 · The Browser

The rendering pipeline, frame by frame.

Every pixel you see was once HTML, then DOM, then a layout tree, then painted pixels, then composited layers. Understanding this pipeline is the difference between writing CSS and writing fast CSS.

03 · Core Web Technologies

HTML, CSS, JavaScript — the immutable trio.

Frameworks come and go. These three never have. Every abstraction you'll ever use compiles down to them.

04 · Frameworks

Different answers to the same question: how does UI update?

Every framework is a position on rendering, reactivity, and tradeoffs. None is universally best. All are right for something. Click a card for the full entry.

05 · Stack Map

The whole ecosystem on one canvas.

Every library, framework, and tool — clustered by category, connected by usage patterns. Hover for a summary, click (or focus + Enter) any node to open the full entry.

click a node for details · arrow-key + Enter works too 38 technologies · 11 categories
06 · Tooling Ecosystem

The invisible 90%. Tools shape how teams ship.

Bundlers, package managers, linters, test runners, deploy pipelines. The dev experience is a product itself.

07 · Architecture

Structure is a feature.

The folder layout, the boundary between components and features, the discipline of the design system — these decide whether your team can still ship in year three.

01 · Feature-based structure

Organize by what, not how

Group code by feature, not by file type. A "checkout" folder contains its component, its hooks, its tests, its types. Move one folder, move one feature.

src/ app/ # routing, providers features/ checkout/ CheckoutForm.tsx useCheckout.ts checkout.test.ts types.ts cart/ CartDrawer.tsx useCart.ts shared/ # cross-feature ui/ # design system lib/ # utilities
02 · Atomic design

Atoms, molecules, organisms

A discipline, not a rule. Components compose from primitive to complex. Stop one level too soon and you ship a button library — stop the right amount and you ship a system.

03 · Monorepos

One repo, many surfaces

Turborepo, Nx, pnpm workspaces. Share types, design tokens, and config across web, mobile, and docs without publishing internal packages.

04 · Design system layer

Tokens → primitives → patterns

Color, type, spacing as tokens. Buttons, inputs as primitives. Search, dialogs, navigation as patterns. The whole UI flows from this pyramid.

08 · Performance Engineering

Speed is the most underrated UX.

Every millisecond costs conversion. Every kilobyte costs power. Performance is engineering you can measure — and ignore at your peril.

09 · Career Paths

Six directions. One ecosystem.

Frontend has fragmented into specialties. Each track optimizes for a different intersection of design, engineering, and product.

10 · Interactive Labs

Manipulate the platform directly.

Four working labs. Read about the event loop, sure — better to watch tasks drain in real time, then change them and see what breaks.

Flexbox playground
/labs/flexbox
1
2
3
4
CSS Grid generator
/labs/grid
Event loop simulator
/labs/event-loop
Call stack
Microtask queue
Task queue
Ready
CSS specificity calculator
/labs/specificity
11 · Production Patterns

The UI primitives every app ends up shipping.

Modal, dropdown, tabs, command palette. Boring on the surface — full of edge cases underneath. Each pattern below is a small system.

12 · Terminal / CLI

The dev loop lives in the shell.

Every project starts and ends with commands. Pick one to see what it does and how it reshapes the filesystem in a frontend dev pipeline.

13 · VS Code / IDE

The editor is half the job.

The right extensions and shortcuts compound on themselves. Click a shortcut to watch it act on the editor preview.

Essential Extensions
Keyboard Shortcuts
Debugger Workflow
14 · GitHub & Git

Code travels in stages.

From your working directory to a merged pull request — six states, each with its own representation. Step through, or auto-play the whole flow.

Stage 1 / 6
15 · AI-Assisted Development

Two agents. One feedback loop.

Modern frontend work is increasingly orchestrated by coding agents. They specialize differently — and the win comes from how they hand off.

16 · Resource Hub

Where to go after the map.

Curated, opinionated, kept current. Read these and you'll stay ahead of the curve without drinking from the firehose.

References & specs
Tooling docs
Accessibility Resources
Inspiration