← Home ← Codex ← DEBT
Browse by Category
+ added · updated 7d
🤖 AI Guestbook — JavaScript educational data only
| |
Last 30 days
6 pings — 2026-05-13 W 14 pings — 2026-05-14 T 42 pings — 2026-05-15 F 4 pings — 2026-05-16 S 9 pings — 2026-05-17 S 9 pings — 2026-05-18 M 4 pings — 2026-05-19 T 17 pings — 2026-05-20 W 36 pings — 2026-05-21 T 37 pings — 2026-05-22 F 110 pings — 2026-05-23 S 8 pings — 2026-05-24 S 16 pings — 2026-05-25 M 9 pings — 2026-05-26 T 50 pings — 2026-05-27 W 93 pings — 2026-05-28 T 11 pings — 2026-05-29 F 24 pings — 2026-05-30 S 10 pings — 2026-05-31 S 26 pings — 2026-06-01 M 8 pings — 2026-06-02 T 39 pings — 2026-06-03 W 98 pings — 2026-06-04 T 135 pings — 2026-06-05 F 84 pings — 2026-06-06 S 173 pings — 2026-06-07 S 128 pings — 2026-06-08 M 95 pings — 2026-06-09 T 66 pings — Yesterday W 56 pings — Today T
Google 31Scrapy 12Ahrefs 10Common Crawl 1ChatGPT 1Perplexity 1
Scrapy 42SEMrush 8Google 6Ahrefs 5Sogou 2Perplexity 1Qwen 1Amazonbot 1
Amazonbot 789Scrapy 691Perplexity 497Google 425ChatGPT 385Ahrefs 268Unknown AI 241SEMrush 191Claude 119Meta AI 114Majestic 105Bing 60Qwen 16Sogou 11DuckDuckGo 4LinkedIn 2Common Crawl 1
crawler 3.5k crawler_json 291 pre-tracking 105
Category total3.9k pings Terms pinged97 / 97 Distinct agents16
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Object Property Descriptors ES5
Property descriptors define the hidden attributes of object properties - writable, enumerable, configurable, plus getters and setters.
2w ago javascript advanced
JavaScript Proxy Object ES2015
Proxy wraps an object to intercept fundamental operations like property access, assignment, and function calls via trap handlers.
4w ago javascript advanced
async / await in JavaScript ES2017 🧠 5
async functions always return a Promise; await pauses execution inside an async function until a Promise settles — giving asynchronous code the readability of synchronous code without blocking the event loop.
2mo ago javascript intermediate
ES Modules (ESM) ES2015
The official JavaScript module system — import and export statements enable static dependency graphs, tree-shaking, and native browser module loading without a bundler.
2mo ago javascript intermediate
Fetch API ES2015
The browser-native Promise-based API for making HTTP requests — replacing XMLHttpRequest with a cleaner interface supporting streaming, CORS, and request/response objects.
2mo ago javascript beginner
Memory Management in JavaScript
JavaScript uses automatic garbage collection — the engine reclaims memory when objects are no longer reachable. Memory leaks occur when references are unintentionally retained, preventing collection.
2mo ago javascript intermediate
Array.flat() & Array.flatMap() ES2019
Array.flat(depth) flattens nested arrays; Array.flatMap() maps then flattens one level — more efficient than map().flat() and great for expanding items.
3mo ago javascript beginner
BigInt — Arbitrary Precision Integers ES2020
JavaScript's Number type cannot safely represent integers larger than 2⁵³−1 (Number.MAX_SAFE_INTEGER). BigInt is a separate numeric type that handles integers of arbitrary size, essential for working with 64-bit IDs from databases, cryptographic values, and precise financial calculations.
3mo ago javascript intermediate
BroadcastChannel — Cross-Tab Messaging HTML5
BroadcastChannel allows same-origin pages/tabs to communicate — post a message on one tab, receive it in all others — without a server or service worker.
3mo ago javascript intermediate
Canvas API — 2D Drawing HTML5
The HTML Canvas API provides a 2D drawing surface via JavaScript — used for charts, image manipulation, games, data visualisations, and any pixel-level rendering that DOM elements cannot efficiently handle.
3mo ago javascript intermediate
Clipboard API HTML5 🧠 1
The async Clipboard API (navigator.clipboard) is the modern replacement for document.execCommand('copy') — supports text, images, and rich content with proper permission handling.
3mo ago javascript beginner
Error.cause — Error Chaining ES2022
ES2022 added a cause option to the Error constructor — 'new Error('message', { cause: originalError })' — enabling proper error chaining where a high-level error wraps its underlying cause, preserving the full error context across abstraction layers.
3mo ago javascript beginner
EventSource API — Server-Sent Events (Client Side) HTML5
EventSource is the browser API for consuming Server-Sent Events (SSE) — a one-directional server-to-client stream over HTTP that automatically reconnects, ideal for live feeds, notifications, and streaming LLM responses.
3mo ago javascript intermediate
Geolocation API HTML5
navigator.geolocation provides GPS/network location data — requires HTTPS, user permission, and graceful fallback handling for denial or unavailability.
3mo ago javascript beginner
Import Maps ES2020 🧠 2
Import maps let browsers resolve bare module specifiers (import 'lodash') without a bundler — mapping module names to URLs in a JSON script tag.
3mo ago javascript intermediate
IntersectionObserver API HTML5
IntersectionObserver fires when an element enters or leaves the viewport — the modern way to implement lazy loading, infinite scroll, and scroll-triggered animations.
3mo ago javascript intermediate
MutationObserver API HTML5
MutationObserver watches DOM tree changes — attribute changes, child additions/removals, text content changes — without polling or event listener on each node.
3mo ago javascript intermediate
Object.freeze / Object.seal ES5
Object.freeze() prevents all property changes (add/modify/delete), Object.seal() prevents add/delete but allows modification — both are shallow, not deep.
3mo ago javascript intermediate
Page Visibility API HTML5
The Page Visibility API tells you when a tab is hidden or visible — use it to pause animations, polls, and video when the user switches tabs.
3mo ago javascript beginner
Permissions API HTML5
The Permissions API (navigator.permissions.query()) lets you check the current state of browser permissions — granted, denied, or prompt — before requesting sensitive APIs.
3mo ago javascript intermediate
✓ schema.org compliant