Lenny RachitskyModify

2026-02-17 00:02:43

Claude Opus 4.6 vs GPT-5.3 Codex: Which is the better software engineer?

Brought to you by WorkOS—Make your app enterprise-ready today

Claire put GPT-5.3 Codex and Claude Opus 4.6 head-to-head on real work—redesigning her marketing site, refactoring complex components, and shipping production code. In five days, she shipped 44 PRs, touched 1,088 files, and added 93,000 lines of code (and deleted 87,000). Her big insight: It’s not Opus or Codex. It’s Opus for building and Codex for reviewing.

Detailed workflow walkthroughs from this episode:

• How I AI: GPT-5.3 Codex vs. Claude Opus 4.6—Shipping 44 PRs in 5 Days: https://www.chatprd.ai/how-i-ai/gpt-5-3-codex-vs-claude-opus-4-6

• How to Combine Claude Opus and GPT-5.3 Codex for High-Velocity Code Refactoring: https://www.chatprd.ai/how-i-ai/workflows/how-to-combine-claude-opus-and-gpt-5-3-codex-for-high-velocity-code-refactoring

• How to Redesign a Marketing Website Using Claude Opus 4.6 for Creative Development: https://www.chatprd.ai/how-i-ai/workflows/how-to-redesign-a-marketing-website-using-claude-opus-4-6-for-creative-development

Biggest takeaways:

1. AI coding tools have reached an inflection point for productivity. Claire shipped 44 PRs containing 98 commits across 1,088 files in just five days—adding 93,000 lines of code and removing 87,000. This included major features like MCP integrations and complete component refactors that would have taken months with a traditional team.

2. The perfect AI engineering workflow combines both models. Claire’s most productive approach was having Opus build features (getting them 80% to 90% complete) and then using Codex to review the code and find edge cases, before returning to Opus to implement the fixes. This mimics a junior–senior developer relationship.

3. Opus 4.6 is the “eager product engineer” who actually builds things. It’s excellent at planning and executing long-running, creative tasks. While its initial design output wasn’t great, it responded well to feedback and ultimately produced a much better redesign than Codex—one that Claire plans to ship to production.

4. GPT-5.3 Codex is the “principal engineer who won’t build anything.” Claire found that while Codex excels at reviewing code and finding edge cases, it struggles with creative, greenfield work. It follows instructions too literally and overfits to the last prompt, making it frustrating for tasks like redesigning a website from scratch.

5. The harness matters as much as the model. Claire found that Cursor’s interface worked better with both models than Codex’s native app. Features like plan mode, to-dos, and exploration tools in Cursor helped get better results from Opus than might have been possible in Claude Code.

6. Opus 4.6 Fast is blazingly fast but expensive. At roughly $150 per million output tokens (six times the price of standard Opus), it’s a significant investment. Claire embraces a “token abundance mindset” because the ROI is still massive compared with traditional development costs.

7. Codex brings Git concepts front and center in its interface. The app emphasizes repositories, branches, work trees, diffs, and pull requests—making it both powerful for experienced developers and educational for those learning Git concepts. This visual approach to Git is more accessible than command-line tools.

8. Skills and automations are becoming first-class citizens in AI coding tools. Codex presents these as visual components with icons and buttons rather than ZIP files, making them more accessible. The included recommended skills and automations provide good starting points for developers.

▶️ Listen now on YouTube | Spotify | Apple Podcasts

How this visually impaired engineer uses Claude Code to make his life more accessible | Joe McCormick

Brought to you by Tines—Start building intelligent workflows today

Joe McCormick is a principal engineer at Babylist who lost most of his central vision right before college. Instead of stepping away from software, he doubled down. And now, with tools like Claude Code, he’s building small, AI-powered Chrome extensions that make his life dramatically more accessible. In this episode, Joe live-builds “micro apps” that describe Slack images, fix typos instantly, and summarize links—all triggered with simple keyboard shortcuts.

Detailed workflow walkthroughs from this episode:

• How I AI: Building Custom AI Accessibility Tools for Slack with Joe McCormick & Claude Code: https://www.chatprd.ai/how-i-ai/custom-ai-accessibility-tools-for-slack-claude-code

• Build a Slack Link Summarizer from Scratch using Claude Code: https://www.chatprd.ai/how-i-ai/workflows/slack-link-summarizer-using-claude-code

• Create a Fast, Accessible AI Spell Checker for Any Website: https://www.chatprd.ai/how-i-ai/workflows/accessible-ai-spell-checker-for-any-website

• Build a Custom AI Tool to Describe Images in Slack: https://www.chatprd.ai/how-i-ai/workflows/ai-tool-to-describe-images-in-slack

Biggest takeaways:

1. AI is closing the gap between sighted and visually impaired engineers. As Joe explains, “The gap between a software engineer for a sighted person and a visually impaired person is closing day by day.” AI tools allow him to work more efficiently by eliminating accessibility barriers that previously required tedious workarounds.

2. Claude Code can be made more screen-reader-friendly with simple techniques. Joe demonstrates several accessibility improvements: using Control+G to edit prompts in a text editor instead of the terminal, creating a sound alert when Claude needs input, and leveraging consistent keyboard patterns (1 for yes, 2 for variations, 3 for no) to navigate options without visual cues.

3. Multimodal AI has transformed personal moments beyond work. Joe shares how Gemini allows him to read any book to his children, something previously impossible without memorizing the text. “I was always afraid of not being able to read stories to my kids. That ‘Sorry, I can’t’ has become ‘Sorry, I can,’ with the assistance of so many different tools now.’”

4. Keyboard shortcuts dramatically improve accessibility efficiency. Joe demonstrates how triggering extensions with keyboard combinations (Ctrl+Shift+D for image descriptions, Ctrl+Shift+S for spell-checking) eliminates multiple clicks and context switches. For someone using a screen reader and 10x magnification, these shortcuts transform tedious tasks into instant actions.

5. Running Slack in Chrome instead of as a desktop app enables powerful customizations. This clever workaround allows Joe to extend Slack’s functionality with Chrome extensions, something impossible with the desktop app. This approach could work for many other web-based tools that offer both desktop and browser versions.

6. Creating Claude Skills accelerates repetitive development tasks. After building his first two Chrome extensions, Joe created a Claude Skill to extract common patterns, making each subsequent extension faster to develop. This compounding efficiency means his fifth extension will take a fraction of the time of his first one.

▶️ Listen now on YouTube | Spotify | Apple Podcasts

If you’re enjoying these episodes, reply and let me know what you’d love to learn more about: AI workflows, hiring, growth, product strategy—anything.

Catch you next week,
Lenny

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2026-02-16 21:03:24

Joe McCormick is a principal software engineer at Babylist who lost most of his central vision due to a rare genetic disorder right before starting college. He pivoted from mechanical engineering to computer science and now leads AI enablement at Babylist. Joe demonstrates how he uses AI to build micro Chrome extensions that make his everyday work and life more accessible, showing how personal software can address accessibility needs that mainstream products often overlook.

What you’ll learn:

1. How to build custom Chrome extensions in under 25 minutes using Claude Code

2. A practical workflow for creating AI-powered accessibility tools

3. How to use Claude Skills to accelerate repetitive development tasks

4. Techniques for making Claude Code more screen reader accessible

5. Why personal software is becoming increasingly viable with AI assistance

6. How multimodal AI is transforming accessibility for visually impaired users

Brought to you by:

Tines—Start building intelligent workflows today

In this episode, we cover:

(00:00) Introduction to Joe and his background

(02:34) Joe’s journey into computer science after vision loss

(04:50) The concept of personal software for accessibility

(06:09) Demo of image description Chrome extension for Slack

(10:40) Demo of AI-powered spell checker extension

(13:12) The efficiency of keyboard shortcuts for accessibility

(14:37) Live building a link summarization extension

(20:28) Using Claude Skills to extract common patterns

(25:30) Reviewing and modifying the development plan

(27:45) Removing cognitive friction for users through repeating patterns

(31:40) How to get fluent with AI tools

(34:55) Loading the extension into Chrome in developer mode

(36:19) Testing and debugging the extension

(40:44) Quick recap

(42:12) Lightning round and final thoughts

Tools referenced:

• Claude Code: https://claude.ai/code

• VS Code: https://code.visualstudio.com/

• Gemini: https://gemini.google.com/

• ChatGPT: https://chat.openai.com/

• Meta Ray-Ban Smart Glasses: https://www.meta.com/smart-glasses/

Other references:

• Chrome Extensions Documentation: https://developer.chrome.com/docs/extensions/

• ARIA (Accessible Rich Internet Applications): https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA

• Windows Subsystem for Linux: https://learn.microsoft.com/en-us/windows/wsl/

• Screen Readers: https://www.afb.org/blindness-and-low-vision/using-technology/assistive-technology-products/screen-readers

• Claude Skills explained: How to create reusable AI workflows:https://www.lennysnewsletter.com/p/claude-skills-explained

Where to find Joe McCormick:

LinkedIn: https://www.linkedin.com/in/joemccormickjr/

Company: https://www.babylist.com/

Where to find Claire Vo:

ChatPRD: https://www.chatprd.ai/

Website: https://clairevo.com/

LinkedIn: https://www.linkedin.com/in/clairevo/

X: https://x.com/clairevo

Production and marketing by https://penname.co/. For inquiries about sponsoring the podcast, email [email protected].

2026-02-15 21:31:20

Brian Halligan co-founded HubSpot, ran it as CEO for about 15 years, and now coaches Sequoia’s fastest-growing founders as their in-house CEO coach.

We discuss:

1. His LOCKS framework for evaluating founders

2. Why you should build your team like the 2004 Red Sox

3. Why hiring “spicy” candidates beats consensus picks

4. Why enterprise sales will be the last white-collar job AI replaces

5. Some of my favorite “Halliganisms”

Brought to you by:

Sentry—Code breaks, fix it faster

Datadog—Now home to Eppo, the leading experimentation and feature flagging platform

WorkOS—Modern identity platform for B2B SaaS, free up to 1 million MAUs

Where to find Brian Halligan

• X: https://x.com/bhalligan

• LinkedIn: linkedin.com/in/brianhalligan

• Delphi: https://www.delphi.ai/bhalligan

• Podcast: https://sequoiacap.com/series/long-strange-trip

Referenced:

• Dev Ittycheria on LinkedIn: https://www.linkedin.com/in/dittycheria

• HubSpot: https://www.hubspot.com

• Parker Conrad on LinkedIn: https://www.linkedin.com/in/parkerconrad

• McKinsey & Company: https://www.mckinsey.com

• Brian Chesky’s new playbook: https://www.lennysnewsletter.com/p/brian-cheskys-contrarian-approach

• Jensen Huang on LinkedIn: https://www.linkedin.com/in/jenhsunhuang

• Winston Weinberg on LinkedIn: https://www.linkedin.com/in/winston-weinberg

• James Cadwallader on LinkedIn: https://www.linkedin.com/in/jsca

• Gabriel Stengel on LinkedIn: https://www.linkedin.com/in/gabestengel

• He saved OpenAI, invented the “Like” button, and built Google Maps: Bret Taylor on the future of careers, coding, agents, and more: https://www.lennysnewsletter.com/p/he-saved-openai-bret-taylor

• Scaling Entrepreneurial Ventures: https://orbit.mit.edu/classes/scaling-entrepreneurial-ventures-15.392

• OpenClaw: https://openclaw.ai

• Ruth Porat on LinkedIn: https://www.linkedin.com/in/ruth-porat

• Mike Krzyzewski: https://goduke.com/sports/mens-basketball/roster/coaches/mike-krzyzewski/4159

• Dalai Lama’s 18 Rules for Living: https://www.prm.nau.edu/prm205/Dalai-Lama-18-rules-for-living.htm

• Zigging vs. zagging: How HubSpot built a $30B company | Dharmesh Shah (co-founder/CTO): https://www.lennysnewsletter.com/p/lessons-from-30-years-of-building

• Kareem Amin on LinkedIn: https://www.linkedin.com/in/kareemamin

• Glassdoor: https://www.glassdoor.com

• Tobi Lütke’s leadership playbook: Playing infinite games, operating from first principles, and maximizing human potential (founder and CEO of Shopify): https://www.lennysnewsletter.com/p/tobi-lutkes-leadership-playbook

• Katie Burke on LinkedIn: https://www.linkedin.com/in/katie-burke-965767a

• Jerry Garcia: https://en.wikipedia.org/wiki/Jerry_Garcia

• Bob Weir: https://en.wikipedia.org/wiki/Bob_Weir

• Phil Lesh: https://en.wikipedia.org/wiki/Phil_Lesh

• Ron “Pigpen” McKernan: https://en.wikipedia.org/wiki/Ron_%22Pigpen%22_McKernan

• Marc Andreessen: The real AI boom hasn’t even started yet: https://www.lennysnewsletter.com/p/marc-andreessen-the-real-ai-boom

• The American Revolution: https://www.pbs.org/kenburns/the-american-revolution

• Delphi: https://www.delphi.ai

• Sonos: https://www.sonos.com

• Yamini Rangan on LinkedIn: https://www.linkedin.com/in/yaminirangan

• The Boston Red Sox: https://www.mlb.com/redsox

Recommended book:

• Marketing Lessons from the Grateful Dead: What Every Business Can Learn from the Most Iconic Band in History: https://www.amazon.com/Marketing-Lessons-Grateful-Dead-Business/dp/0470900520

Production and marketing by https://penname.co/. For inquiries about sponsoring the podcast, email [email protected].

Lenny may be an investor in the companies discussed.

My biggest takeaways from this conversation:

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2026-02-15 01:03:27

👋 Hello and welcome to this week’s edition of ✨ Community Wisdom ✨ a subscriber-only email, delivered every Saturday, highlighting the most helpful conversations in our members-only Slack community.

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2026-02-12 21:31:43

Sherwin Wu leads engineering for OpenAI’s API platform, where roughly 95% of engineers use Codex, often working with fleets of 10 to 20 parallel AI agents.

We discuss:

1. What OpenAI did to cut code review times from 10-15 minutes to 2-3 minutes

2. How AI is changing the role of managers

3. Why the productivity gap between AI power users and everyone else is widening

4. Why “models will eat your scaffolding for breakfast”

5. Why the next 12 to 24 months are a rare window where engineers can leap ahead before the role fully transforms

Brought to you by:

DX—The developer intelligence platform designed by leading researchers

Sentry—Code breaks, fix it faster

Datadog—Now home to Eppo, the leading experimentation and feature flagging platform

Where to find Sherwin Wu:

• X: https://x.com/sherwinwu

• LinkedIn: https://www.linkedin.com/in/sherwinwu1

Referenced:

• Codex: https://openai.com/codex

• OpenAI’s CPO on how AI changes must-have skills, moats, coding, startup playbooks, more | Kevin Weil (CPO at OpenAI, ex-Instagram, Twitter): https://www.lennysnewsletter.com/p/kevin-weil-open-ai

• OpenClaw: https://openclaw.ai

• The creator of Clawd: “I ship code I don’t read”: https://newsletter.pragmaticengineer.com/p/the-creator-of-clawd-i-ship-code

• The Sorcerer’s Apprentice: https://en.wikipedia.org/wiki/The_Sorcerer%27s_Apprentice_(Dukas)

• Quora: https://www.quora.com

• Marc Andreessen: The real AI boom hasn’t even started yet: https://www.lennysnewsletter.com/p/marc-andreessen-the-real-ai-boom

• Sarah Friar on LinkedIn: https://www.linkedin.com/in/sarah-friar

• Sam Altman on X: https://x.com/sama

• Nicolas Bustamante’s “LLMs Eat Scaffolding for Breakfast” post on X: https://x.com/nicbstme/status/2015795605524901957

• The Bitter Lesson: http://www.incompleteideas.net/IncIdeas/BitterLesson.html

• Overton window: https://en.wikipedia.org/wiki/Overton_window

• Developers can now submit apps to ChatGPT: https://openai.com/index/developers-can-now-submit-apps-to-chatgpt

• Responses: https://platform.openai.com/docs/api-reference/responses

• Agents SDK: https://platform.openai.com/docs/guides/agents-sdk

• AgentKit: https://openai.com/index/introducing-agentkit

• Ubiquiti: https://ui.com

• Jujutsu Kaisen on Crunchyroll: https://www.crunchyroll.com/series/GRDV0019R/jujutsu-kaisen?srsltid=AfmBOoqvfzKQ6SZOgzyJwNQ43eceaJTQA2nUxTQfjA1Ko4OxlpUoBNRB

• eero: https://eero.com

• Opendoor: https://www.opendoor.com

Recommended books:

• Structure and Interpretation of Computer Programs: https://www.amazon.com/Structure-Interpretation-Computer-Programs-Engineering/dp/0262510871

• The Mythical Man-Month: Essays on Software Engineering: https://www.amazon.com/Mythical-Man-Month-Software-Engineering-Anniversary/dp/0201835959

• There Is No Antimemetics Division: A Novel: https://www.amazon.com/There-No-Antimemetics-Division-Novel/dp/0593983750

• Breakneck: China’s Quest to Engineer the Future: https://www.amazon.com/Breakneck-Chinas-Quest-Engineer-Future/dp/1324106034

• Apple in China: The Capture of the World’s Greatest Company: https://www.amazon.com/Apple-China-Capture-Greatest-Company/dp/1668053373

Production and marketing by https://penname.co/. For inquiries about sponsoring the podcast, email [email protected].

Lenny may be an investor in the companies discussed.

My biggest takeaways from this conversation:

Read more

2026-02-11 21:02:52

I put the newest AI coding models from OpenAI and Anthropic head-to-head, testing them on real engineering work I’m actually doing. I compare GPT-5.3 Codex with Opus 4.6 (and Opus 4.6 Fast) by asking them to redesign my marketing website and refactor some genuinely gnarly components. Through side-by-side experiments, I break down where each model shines—creative development versus code review—and share how I’m thinking about combining them to build a more effective AI engineering stack.

What you’ll learn:

1. The strengths and weaknesses of OpenAI’s Codex vs. Anthropic’s Opus for different coding tasks

2. How I shipped 44 PRs containing 98 commits across 1,088 files in just five days using these models

3. Why Codex excels at code review but struggles with creative, greenfield work

4. The surprising way Opus and Codex complement each other in a real-world engineering workflow

5. How to use Git concepts like work trees to maximize productivity with AI coding assistants

6. Why Opus 4.6 Fast might be worth the 6x price increase (but be careful with your token budget)

Brought to you by:

WorkOS—Make your app enterprise-ready today

In this episode, we cover:

(00:00) Introduction to new AI coding models

(02:13) My test methodology for comparing models

(03:30) Codex’s unique features: Git primitives, skills, and automations

(09:05) Testing GPT-5.2 Codex on a website redesign task

(10:40) Challenges with Codex’s literal interpretation of prompts

(15:00) Comparing the before and after with Codex

(16:23) Testing Opus 4.6 on the same website redesign task

(20:56) Comparing the visual results of both models

(21:30) Real-world engineering impact: 44 PRs in five days

(23:03) Refactoring components with Opus 4.6

(24:30) Using Codex for code review and architectural analysis

(26:55) Cost considerations for Opus 4.6 Fast

(28:52) Conclusion

Tools referenced:

• OpenAI’s GPT-5.3 Codex: https://openai.com/index/introducing-gpt-5-3-codex/

• Anthropic’s Claude Opus 4.6: https://www.anthropic.com/news/claude-opus-4-6

• Cursor: https://cursor.sh/

• GitHub: https://github.com/

Other references:

• Tailwind CSS: https://tailwindcss.com/

• Git: https://git-scm.com/

• Bugbot: https://cursor.com/bugbot

Where to find Claire Vo:

ChatPRD: https://www.chatprd.ai/

Website: https://clairevo.com/

LinkedIn: https://www.linkedin.com/in/clairevo/

X: https://x.com/clairevo

Production and marketing by https://penname.co/. For inquiries about sponsoring the podcast, email [email protected].