Addy Osmani

Production-grade engineering skills for AI coding agents.

Extract & Inline Critical-path CSS in HTML pages

Agent Skills for optimizing web quality based on Lighthouse and Core Web Vitals.

Multi-agent adversarial code review for any coding agent

🦖 Google Chrome Dino 3D with AI

A Webpack plugin for Lighthouse

Agent Engineer - a practical course for software engineers

Agentic SEO / Agentic Engine Optimization (AEO) tools

The highest-scoring AI memory system ever benchmarked. And it's free.

Extract URLs to stylesheets, scripts, links, images or HTML imports from HTML

AI agent skill that researches any topic across Reddit, X, YouTube, HN, Polymarket, and the web - then synthesizes a grounded summary

GitHub README

A minimal VLC port that works in the browser

Experimental VLC for the browser built using a VLC WASM port

ChattyUI - your private AI chat for running LLMs in the browser

Use Gemini to decide which Pexels videos to download for your project

ADK apps for Product Engineers

JARVIS built using the Gemini Live API

Free full-featured web-based audio & waveform editing tool (with AI features)

Say - A Whisper AI Notes app

Gemini CLI Tips and Tricks

Context Buddy is a quick educational aid for understanding Context Engineering

Cam

A visual bookmark organizer for Chrome using built-in AI

Vanilla JavaScript for React developers

A React Coverflow component using Scroll-driven Animations

Cover Flow effect implemented with Three.js

A real-time 3D fluid simulation implemented in WebGPU (immersive version)

A script and resource loader for caching & loading files with localStorage

Demo of ElevenLabs new Scribe ASR model

ElevenLabs Diarization Demo

📹 Record is an open-source web app to record screen and camera directly in your browser | No installation required | No tracking | Fully local

Repro of "The Tunnel Bear" login page

Video compression in the browser using FFMPEG.wasm

Squish - Batch Browser-based Image Compression

Filter - Web Image Editor

Free image background removal - private, client-side and powered by Transformers.js

Enhance and upscale your images using AI - right in your browser

Fireworks in your terminal 🎆

Free document to PDF scanner

:book: A creative-commons book on Backbone.js for beginners and advanced users alike

CLI tool to convert GitHub repositories to text files for LLMs

Next.js View Transitions - Movies demo

Experiments in multi-platform model serving

List movies from TMDB API. Made with Remix, and NextUI.

A simple, git-clone friendly starting point for personal projects.

Learning JavaScript Design Patterns: 2nd Edition - The Examples

A quick example of how one can "synchronize" a 3d scene across multiple windows using three.js and localStorage

The frontend, backend, and content source code for developer.chrome.com

Make images smaller using best-in-class codecs, right in the browser.

Next.js supports 4 rendering strategies to generate, deliver and render a React Single Page App on the client side: SSG, SSR, ISR and CSR.

Angular 4.x TodoMVC implementation

Automating Web Performance testing with Puppeteer 🎪

Network-aware adaptive loading with Lottie Web

Tools to prioritize above-the-fold (critical-path) CSS

Repo for my 'Learning JavaScript Design Patterns' book

Create EPUBs with markdown or plain HTML (and more). Built on 11ty.

Above-the-fold CSS generation + inlining using Critical & Gulp

A simple tags input with typeahead (autocomplete) built with Vue.js 2.

A bookmarklet for prettifying your CSS

Bubble Sort implementation with O(n^2) complexity.

Accessibility-friendly version of TMDB Viewer (load-more)

A movie browsing/favoriting app (fork using react-window)

Navigation Timing API measurement helpers

Automated auditing, performance metrics, and best practices for the web.

FireBug for designers › Edit any webpage, in any state https://a.nerdy.dev/gimme-visbug

An aggregation of tooling for using ES6 today

Draft proposal for browser-level media resizing

The place to share queries, ideas, or issues related to the Chrome UX Report

The source code of v8.dev, the official website of the V8 project.

Sample Gulp project using PSI

My dot files (in need of updating to my latest)

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A VSCode extension to host the chrome devtools inside of a webview.

Build blazing fast, modern apps and websites with React

"Shrine" Progressive Web App sample built with React

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📉 Visualisation layer and data store for SpeedTracker

Improve performance by predictively fetching pages a user is likely to need

Accessibility audit tooling for the web (beta)

A browser API to enable developers signal the priorities of the resources they need to download.

Smaller Pics Progressive Web App

Long Task API

Network emulation / throttling conditions (2G, 3G, 4G, Wifi etc) ☎️

No description.

Shim for getUserMedia(). Uses native implementation for modern browsers and a Flash fallback for everyone else.

😺 Your next Preact PWA starts in 30 seconds.

TodoMVC built using the Vue.js 2.0 CLI 🍰

WIP - ES6 Equivalents In ES5

🗞 Preact Hacker News

A declarative, efficient, and flexible JavaScript library for building user interfaces.

TMI (Too Many Images) - discover your image weight on the web

Enhances html-webpack-plugin functionality with different deployment options for your scripts including 'async', 'defer', 'module' and inlining.

Auto chunking and dynamic loading of routes with React Router and Webpack 2

Browser-friendly helper for parsing DevTools Timeline traces into structured profiling data models

Instrument your JavaScript to measure parse & execution time on any device or browser

Traces 😘

:book: Preact documentation website.

Module bundling study (with Lighthouse)

:fire: A highly scalable, offline-first foundation with the best developer experience and a focus on performance and best practices.

🎩 A helper for working with individual Progressive Web App metrics (via Lighthouse)

Quick module for getting Lighthouse reports in JSON form

Ember.js Zuperkulblog PWA (built with FastBoot and ember-cli)

A Polymer element for paginating model data

🗃 Comparing storage options for the open web in 2016

Another Pub/Sub implementation

Angular 1 Dribbble Progressive Web App demo

A repo of up to date examples using Yeoman

A Polymer element for Mozilla's localForage (async storage via IndexedDB or WebSQL)

SublimeText package for FixMyJS

Demo of Polymer + Paper elements working off npm3

A cross-browser Page Visibility API shim

Responsive images using Imager.js and Polymer

ES2015 TodoMVC app that works without a transpiler

A Polymer element for syntax highlighting with Prism.js

Yeoman generator with grunt-uncss

dotfiles for Windows, including Developer-minded system defaults. Built in PowerShell

Polymer filters for formatting values of expressions.

A11y WebApp built with Polymer (WIP)

Leaking future secrets

Recursive Binary Search with O(log N) complexity

Selection sort with O(n^2) time complexity

Scalable JS architecture demo for #jqcon

[Deprecated] Use gulp-uncss instead please.

[Deprecated] A Polymer element for querying the Instagram API (Note: not yet updated to Polymer 0.5.x)

SocketChat - a beginners chat app using SocketStream

Default channel file for Package Control. Follow the directions at:

Polymer + Material Timer/Countdown/Countdown app (alpha)

I don't even.

V8 memory mysteries (sample app)

A faster JavaScript memoizer

A Polymer element for Video.js

Critical-path CSS optimized weather app

Run browser-perf on websites

Todo app using vanilla Web Components

Above-the-fold CSS generation + inlining using Critical, Gulp & Angular

An Embeddable GitHub 'Watchers' Button For External Pages

Active view routing for Polymer extending <template>

A tabs component using Polymer core-elements

A Polymer.js template for building fast, robust web apps using Web Components

An Undo/Redo manager as a Polymer element

Experiments with Mutation Observers & Object.observe()

<sparkle-trail> Polymer element - useful as a pre-loader

A simple Yeoman generator using Git submodules to clone over a boilerplate hosted elsewhere on GitHub

A Polymer element for <video> with playback speed controls

A YouTube Jukebox element built with Polymer & Yeoman

A special build of mustache that works in Chrome Apps under CSP

A Polymer event emitter element with support for wildcards, many and once.

Remove unused styles from CSS

(WIP) - A DevTools extension for multi-page unused CSS auditing

A tutorial app for generator-polymer

A collection of helpful snippets to use inside of browser devtools

Polymer + Grunt

A site providing a list of secrets for the Browser Developer Tools in Chrome, Firebug, Firefox, Internet Explorer, Opera and Safari.

Yeoman generator for Chrome App

Backbone.js stack boilerplates demonstrating integration with Express, Ruby, PHP, Grails and more.

A scalable, event-driven JavaScript architecture for developing widget-based applications. Works with Backbone.js and other frameworks.

dotJS website

Sublime Text build systems

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A todo app in Meteor.js, inspired by todomvc

Brunch skeleton with structure of Chaplin

A Backbone.js + jQuery Mobile sample app using AMD for separation of modules, Require.js for dependency management + template externalisation and Underscore for templating

HTML5 Video Face Detection with the CCV Javascript Library

Give your JS App some Backbone with Models, Views, Collections, and Events

Raw browser/feature support data from caniuse.com

Backbone Koans for QUnit

[Deprecated] A validation plugin for Backbone.js

[Deprecated] An AMD-compatible startup pack for developers using Require.js and Backbone.js in their projects.

A set of jasmine powered koans for learning Backbone.js.

Bootstrap themed jQueryUI date range picker

A small utility for parsing URLs of all types.

Another compact micro-templating solution

jQuery JavaScript Library

contextMenu plugin & polyfill

Sample Todos application built using SproutCore 2.0

A todo list app written on top of Sammy.js

A Simple Todo app written with JavaScriptMVC

Backbone.js todos example done with Knockout.js

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Hash history/routing management

A Backbone alternative idea

(Demo app) A Spine.js Bit.ly client for shortening URLs and archiving references to these links offline.

A demonstration project showing how a simple yet effective 'hover-focused' UI can be implemented

CSS3 Transition Fallback demos

A Client-side ANT Build File Example

A Backbone, Underscore and jQuery Templates based image gallery (early early beta)

Demos for upcoming issues of .NET magazine

Fake fork of Paul Irish's image loaded method for jQuery

NoJs HTML5 Template is a cross-browser JavaScript-less webpage template

A project to provide playlist capabilities around the LongTail HTML5 Video Player

jQuery Community Updates

A compact Google Viewer plugin

No description.

Miscellaneous small jQuery plugins and code fragments

A jQuery plugin for plotting interactive content galleries in a circle form

A minimalist JavaScript library for drawing objects around a Circle or Ellipse