Addy Osmani

Engineering and evangelism leader

Addy Osmani is an Irish engineering and evangelism leader who spent over 14 years at Google. Most recently he was a Director at Google Cloud AI, running Cloud AI Developer Experience and Technical Evangelism and helping launch Google's agent developer platform (Agent Platform, Agent CLI, and Agent Studio). Before that he led Developer Experience across Chrome, DevTools, Lighthouse, and Core Web Vitals, and increasingly focused on AI: Gemini's developer experience, coding agents, evals, and 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 author of books including Learning JavaScript Design Patterns, Leading Effective Engineering Teams, Stoic Mind, and Image Optimization, and has given over 175 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

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.

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.

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.

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.

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 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.

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

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

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.

Modern Web Apps - a guide to writing high-performance React web applications 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.

Developer Experience

The Stoic Mind: By Addy Osmani and 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.

Image Optimization by Addy Osmani. A Smashing Magazine title.

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.

New perspectives on web design

Backbone Fundamentals

Case Studies

eBay

Netflix

Tinder

Pinterest

Treebo

YouTube

Adobe

Twitter web case study

Pictured: Addy Osmani.

Featured AI articles

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

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

Loop Engineering thumbnail

Loop Engineering

The Intent Debt thumbnail

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

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Agent Harness Engineering

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Agentic Engine Optimization (AEO)

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Your parallel Agent limit

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.

Open-source

Projects I've contributed to include Lighthouse, Workbox, Quicklink, Guess.js, Yeoman, TodoMVC, Speedometer, Critical and Material Design Lite. You can find more on my open-source page or on GitHub.
Podcasts

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

Recordings of my talks are on my YouTube channel. These include Optimize the Core Web Vitals and Cost Of JavaScript. You can find some of my slides on SpeakerDeck.
Blog

You can find my writing on my blog, Substack and on LeadDev. My last post on here was: Human judgment doesn't leave the software factory. It relocates.

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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TikTok - Music

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YouTube - Tutorials

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Substack - Articles