Addy Osmani

Engineering and evangelism leader
Addy Osmani is an Irish engineering and evangelism leader and a Member of Technical Staff at Anthropic. He works on Claude Code. He spent over 14 years at Google, most recently as a Director at Google Cloud AI, running Cloud AI Developer Experience and Technical Evangelism and helping launch Google's agent developer platform. Before that he led Developer Experience across Chrome, DevTools, Lighthouse, and Core Web Vitals, and Gemini's developer experience (coding agents, evals, code quality). A developer for 25+ years, and earlier an engineer on Fortune 500 sites, he is passionate about AI-assisted engineering and developer tools. He is the of books including Learning JavaScript Design Patterns, Leading Effective Engineering Teams, Stoic Mind, and Image Optimization, and has given over 200 talks worldwide. You can find his writing on his blog, Substack, and LeadDev, his code in open source, and him on LinkedIn, Twitter, and TikTok.

Books

Code generation has become cheap. Verification has not. As AI agents take on more of the development process, the bottleneck has moved from writing code to deciding what to build, directing agents to build it, and being able to answer for what ships. Agentic Engineering is a guide to making that shift deliberately and delegating work without giving up control: designing harnesses that give agents the right context, tools and goals, writing specs and skills that support reliable delegation, orchestrating multiagent and long-running workflows, and building stopping conditions, evaluations and review into the loop.

Agentic Engineering

by Addy Osmani

On today's web, performance isn't just a nice-to-have—it's essential. A slow or unstable experience drives users away, while a fast, reliable one builds trust and keeps them engaged. Web Performance Engineering in the Age of AI is a comprehensive, hands-on guide for developers, technical leads, and performance engineers focused on delivering high-impact, user-first web experiences.

Web Performance Engineering

by Addy Osmani

The software engineering landscape is constantly evolving, and the demands on engineers intensify with each technological and methodological shift. In such an environment, being a good coder isn't enough—true effectiveness goes beyond technical skills. This book is designed as a guide for individual contributors who want to level up to meet the challenges of a changing industry.

The Effective Software Engineer

by Addy Osmani

Beyond Vibe Coding is a practical guide by Addy Osmani on maintaining code quality in the age of AI-assisted development. It explores how to treat AI like a junior developer, ensuring that code meets your standards, remains understandable, and aligns with your team's practices. The book covers strategies for avoiding common pitfalls with AI-generated code and emphasizes discipline, testing, and maintainability in modern software workflows.

Beyond Vibe Coding

by Addy Osmani

Effective Software Engineering Management: A practical handbook for leading modern software teams with frameworks for building trust, shaping culture, and connecting execution to business outcomes.

Effective Software Engineering Management

by Addy Osmani

AI-assisted coding and cloud-based tools are already transforming how modern applications are built. Bolt.new, a powerful in-browser AI agent from StackBlitz, streamlines the development process, allowing you to prototype quickly, debug intelligently, and launch confidently—no local setup required. Whether you're new to full stack development or looking to supercharge your workflow, this accessible guide takes you from JavaScript and React fundamentals all the way to deploying sophisticated apps with Bolt.new and StackBlitz. Through real-world projects like a movie explorer and a Supabase-powered workout tracker, you'll master prompt-first development, tap into WebContainers for running backend logic in the browser, and discover a seamless path from idea to deployment. If you're ready to rethink how web apps are built—from the command line to the cloud—this book is your blueprint.

Building Web Apps with Bolt

by Addy Osmani

Building Large Scale Web Apps is a toolkit to managing large-scale React applications. React as a library allows you to start building user interfaces quickly and easily. But how do things scale as an application grows? How do you ensure that your codebase remains manageable, your performance metrics stay on point, and your team continues to work cohesively as the project evolves? In this book, you'll uncover strategies that industry professionals use to build scalable, performant, and maintainable React applications, all without becoming overwhelmed by complexity.

Building large-scale web apps

by Addy Osmani

Leading Effective Engineering Teams - a book of growth tips for engineers, tech leads and managers by Addy Osmani

Effective Eng. Teams

by Addy Osmani

Product Engineering with AI - A book bundle about building AI-powered products, from foundations to real-world implementation.

Product Engineering with AI

by Addy Osmani

Do you want to write beautiful, structured, and maintainable JavaScript by applying modern design patterns to the language? Do you want clean, efficient, manageable code? Want to stay up-to-date with the latest best practices? If so, the updated second edition of Learning JavaScript Design Patterns is the ideal place to start. Author Addy Osmani shows you how to apply modern design patterns to JavaScript and React. That includes popular design patterns such as modules, mixins, observers, and mediators. You'll learn about performance and rendering patterns, such as server-side rendering and islands architecture. You'll also learn how modern architectural patterns—such as MVC, MVP, and MVVM—are useful from the perspective of a modern web application developer. Other essential topics include modern JavaScript syntax and React patterns such as Hooks, higher order components, and render props.

JS Patterns: 2nd Edition

by Addy Osmani

Modern Web Apps - a guide to writing high-performance React web applications by Lydia Hallie and Addy Osmani

Learning Patterns

by Lydia Hallie and Addy Osmani

Success at Scale is a curated collection of best-practice case studies capturing how production sites of different sizes tackle performance, accessibility, capabilities, and developer experience at scale. Case studies are from industry experts with guidance that stands the test of time.

Success at Scale

by Addy Osmani

Developer Experience

Developer Experience

by Addy Osmani

The Stoic Mind: By Addy Osmani and GoLimitless

The Stoic Mind

by Addy & GoLimitless

In Software Engineering - The Soft Parts Addy Osmani shares lessons from his first 10 years at Google on the soft skills that can help engineers become effective and scale their effectiveness. This guidance should help junior, mid-career and even senior developers move forward, deal with changing technology, and navigate building non-trivial systems. Becoming a good engineer is about collecting experience. Each project, even small ones, is a chance to add new techniques and tools to your toolbox. Where this delivers even more value is when you can solve problems by pairing techniques learned on one project with tools learned working on another. This short book tries to capture what the soft skills are and how they can all add up.

SoftEng - The Soft Parts

by Addy Osmani

Image Optimization by Addy Osmani. A Smashing Magazine title.

Image Optimization

by Addy Osmani

Explore many popular design patterns, including Modules, Observers, Facades, and Mediators. Learn how modern architectural patterns—such as MVC, MVP, and MVVM—are useful from the perspective of a modern web application developer. This book also walks experienced JavaScript developers through modern module formats, how to namespace code effectively, and other essential topics.

JS Design Patterns

by Addy Osmani

New perspectives on web design

Featured: SM Book 4

by Addy Osmani

Backbone Fundamentals

Backbone Applications

by Addy Osmani

Case Studies

eBay logo.

eBay

Netflix

Netflix

Tinder

Tinder

Pinterest

Pinterest

Treebo

Treebo

YouTube

YouTube

Adobe case study

Adobe

Twitter web case study

Twitter

Pictured: Addy Osmani.

Featured AI articles

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Brownfield Agentic Engineering

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Agentic Skill Decay

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Audit your Agent files

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Human judgment doesn't leave the software factory. It relocates.

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Practical Loop Engineering

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Agentic Code Quality

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Software Factories, Light and Dark

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Own the Outer Loop

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Earning taste and judgment

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The Agent-Era Career

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Agentic Autonomy Levels

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The New Software Lifecycle

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Agentic Code Review

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Loop Engineering

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The Intent Debt

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The Orchestration Tax

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Don't Outsource the Learning

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Cognitive Surrender

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Agent Skills

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Long-running Agents

 

Featured thoughts

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Critical Thinking is key

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Overcome team dysfunction

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Work is a subset of life

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Coach, mentor, sponsor

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Effective engineers

Check out more of my thoughts on LinkedIn.

  1. Open-source

    Projects I've contributed to include Lighthouse, Workbox, Quicklink, Guess.js, Yeoman, TodoMVC, Speedometer, Critical and Material Design Lite. More recently I've been building for coding agents: agent-skills, a set of production-grade engineering skills for AI coding agents, and clarity, an agent skill for clearer writing. You can find more on my open-source page or on GitHub.

  2. Podcasts

    I have been on a few podcasts recently, including The Pragmatic Engineer and Beyond Coding.

  3. Talks

    Recordings of my talks are on my YouTube channel. My most recent is Don't Build Agents You Can't Answer For, the closing keynote at AI Engineer. Earlier ones include Optimize the Core Web Vitals and Cost Of JavaScript. You can find some of my slides on SpeakerDeck.

  4. Film

    I appear in The Story of VS Code, the official documentary about Visual Studio Code. There is a short trailer too.

  5. Blog

    You can find my writing on my blog, Substack and on LeadDev. My last post on here was: Brownfield Agentic Engineering

Featured Videos

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Beyond Vibe Coding

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The AI-Assisted Developer Workflow

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How to become a "T-shaped" software engineer
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Life Lessons

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Effective Engineering Teams

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Cost Of JavaScript

Check out more of my videos on YouTube.

Shorts

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How to become an effective engineer?

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Habits that may be slowing you down

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Are you a T-shaped engineer?

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Why asking why can help you build better software

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IC vs manager which path is right for you

My Network

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Instagram - Motivational Tips

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TikTok - Motivational Tips

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YouTube - Tutorials

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Substack - Articles