Frontend

An HTML reference for building accessible, semantic web pages — document structure, text, lists, links & images, tables, forms, and the semantic tags that convey meaning to both browsers and screen readers.

A CSS reference for styling pages without a framework, covering selectors, the box model, Flex/Grid layout, positioning, transitions & animation, and responsive patterns for both desktop and mobile.

An Emmet abbreviation reference for anyone writing HTML/CSS by hand in VSCode, covering structure expansion, nesting & grouping, attribute and counter shortcuts, and CSS shorthand that turns long markup into a single keystroke.

A Flexbox layout reference for building one-dimensional responsive layouts, covering container vs item properties, main-axis and cross-axis alignment, grow/shrink/basis sizing, and the classic toolbar, card, and centered layouts that Flexbox handles naturally.

A CSS Grid reference for building two-dimensional page layouts, covering grid-template definitions, track sizing with fr/minmax, named areas and line placement, alignment, and responsive patterns that adapt without media queries.

An HTML meta tags reference for controlling how a page appears in search and on social — SEO meta, Open Graph & Twitter Cards for sharing, viewport & responsive/theme settings, PWA manifest & theme-color, and security headers such as CSP.

A Tailwind CSS reference for developers who build interfaces directly with utility classes — layout Flex/Grid, spacing, typography, colors, responsive breakpoints, dark mode, and animation — and the trade-offs of on-demand generation and class composition.

A Next.js reference for React developers weighing SSR vs SSG, covering App Router routing and layouts, the client/server component boundary, data fetching, API routes, middleware, the static-generation vs ISR trade-off, and how the cache hierarchy affects update freshness.

A Svelte reference for developers who prefer minimal runtime and compile-time reactivity, covering reactive declarations (let and $:), template syntax, events and dispatch, component communication, lifecycle, Store, and built-in transitions — and how Svelte removes a virtual-DOM runtime from the box.

An ES6+ syntax reference for frontend and full-stack developers: let/const, arrow functions, destructuring, template literals, higher-order array methods, and Promise/async-await — the patterns used most in everyday React/Vue and Node code, ready to reuse.

For JS devs adding static types to a codebase: from basic types, interfaces and union types, to generic constraints and utility types like Partial/Pick/Omit — explained with copyable examples.

A Lodash quick reference for writing safer, shorter JS without hand-rolling helpers: array transforms, safe nested property access, deep clone & merge, debounce/throttle, and handy math utilities. Copy and run.

A Vue 3 reference for building reactive UIs with the Composition API: ref/reactive/computed/watch, lifecycle hooks, props-emits-provide-inject communication, router, Pinia state, and template/render optimization. Copy and run.

A React 18 reference for building component UIs with Hooks: state and effects, advanced Hooks like useReducer/Context, component patterns, controlled forms, and performance tweaks (memo, lazy, Suspense). Copy and run.

npm commands across project init/scaffolding, install/update/remove, version management and lockfiles, script running and npx, dependency inspection and auditing, publishing, and config/cache. For running a Node.js project's full lifecycle without leaving the terminal.

Webpack configuration covering entry/output, Loaders for assets, Plugins, the dev server and HMR, code splitting and bundle optimization, and mode/environment. For assembling a frontend build pipeline and fixing slow or bloated builds.

Jest testing APIs covering test cases and grouping (describe/it), matchers and assertions, async testing, mock functions and module mocking, snapshot tests, and coverage reports. For writing JavaScript unit tests that fail for the right reason.

Vite cheat sheet — complete command reference for project scaffolding, the dev server, production build, environment variables, plugins, proxy and SSR builds, plus how Vite's workflow differs from Webpack-era tooling.