Advanced everything in Frontend Dev, page 11
Angular: Dynamic Component Loading
Programmatically create and render components anywhere in your app, not just where you've hardcoded them. Use it for dynamic dashboards or modal dialogs. The footgun is forgetting to manually destroy components, which leads to memory leaks.
Angular View Encapsulation: Walling Off Your Component Styles
View Encapsulation walls off a component's CSS to prevent styles from leaking in or out. By default, Angular emulates a Shadow DOM to scope styles, but you can change this. The footgun is using None to fix a style, creating global CSS conflicts.
Svelte Slot Props: Child Informs, Parent Renders
Svelte slot props let a child component pass data up to its parent's slot. This is key for reusable list components where the child provides data for each item, but the parent controls the rendering. The footgun: the let: directive goes on the component tag.
Vite's Dependency Pre-Bundling
Vite's dev server pre-bundles dependencies to accelerate local development. It converts CommonJS modules to browser-native ESM and merges packages with many files into one, preventing massive HTTP request chains.
SvelteKit Hooks: Intercepting Requests and Events
SvelteKit Hooks are like middleware, letting you intercept requests and events to run app-wide logic. Use them for tasks like authentication checks, initializing DB clients, or custom routing.
Vite's Low-Level SSR API
Vite's SSR API lets you run Vite as a middleware inside your own Node.js server, giving you full control over rendering. It's for building custom SSR solutions, often with Express. The footgun: most apps should use a higher-level SSR plugin, not this API.
Vue's Reactivity: JavaScript That Acts Like a Spreadsheet
Vue's reactivity system makes your data act like a spreadsheet: change a value, and dependent parts of your app update automatically. It works by wrapping your data in special objects. The footgun: reactivity is lost if you replace a whole object.
TypeScript Namespaces: The Original Module System
TypeScript namespaces bundle related code under a single global name, preventing name collisions. They are useful for older projects or UMD library types, but the footgun is using them in modern apps; prefer standard ES modules.
Speed Up Builds with TypeScript Project References
Treat your codebase like a set of independent packages. Project References let you split a large project into smaller, interconnected pieces, dramatically speeding up builds by only recompiling what's changed.
Media Source Extensions: The Engine for Web Streaming
MSE lets you build streaming video players in JavaScript by feeding media chunks to a <video> element, instead of a single file URL. It's the foundation for adaptive streaming like DASH/HLS.
RTCPeerConnection: Direct Browser-to-Browser Links
Think of an RTCPeerConnection as a direct phone line between two browsers. It's the core of WebRTC, enabling peer-to-peer video and data streams. The footgun: it doesn't find peers; you must use a separate signaling server to broker the initial handshake.
WebGL Textures: From Image File to GPU Pixels
WebGL textures are images uploaded to the GPU for fast access when "painting" 3D models. They're used to apply detailed surfaces like brick patterns. The footgun: images must be CORS-approved, and non-power-of-two dimensions break mipmapping in WebGL1.
Web Audio API: A Modular Synth for Your Browser
The Web Audio API treats sound as a modular graph. You connect sources (files, oscillators) to effects (filters) and a destination (speakers) for precise, low-latency control. It's ideal for games and music apps.
Web Push API: Engage Users When Your App is Closed
The Web Push API lets servers send messages to users even when your site is closed. A service worker receives these pushes, making it ideal for notifications. The main footgun: the subscription endpoint is a secret key that must be protected.
Background Sync API: Send Data When the Network Returns
The Background Sync API lets your app defer work until the network is back. You register a task, and the browser wakes your service worker to run it when connectivity returns. Use it to reliably send data submitted while offline, like form posts or chat.
Transferable Objects: Zero-Copy Data for Web Workers
Transferable Objects move resource ownership between contexts, like threads, instead of copying data. This enables fast, 'zero-copy' transfers for large memory blocks. Use it with postMessage() to send an ArrayBuffer to a Web Worker.
Shared Workers: One Background Script for Multiple Tabs
A SharedWorker is a single background script shared across multiple tabs or windows from the same origin. Use it to manage a single WebSocket connection or sync state between pages. The footgun: each tab must call port.start() on its own message port.
Cache API: Manual Control Over Network Responses
The Cache API is a key-value store for network requests you control directly, unlike the browser's automatic HTTP cache. Use it in service workers for offline support or to pre-cache app assets.
IndexedDB Versioning: The 'upgradeneeded' Gatekeeper
IndexedDB uses a version number to manage schema changes. Incrementing the version in indexedDB.open() triggers a special upgradeneeded event, which is the only context where you can create or modify object stores and indexes.
IndexedDB Cursors: Iterate Large Datasets Efficiently
An IndexedDB cursor is a pointer for walking through records one by one, avoiding loading a whole dataset into memory. Use it to efficiently process large browser databases.
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