Claude Code vs. Codex in-depth

Plus, coffee increases testosterone, a new David video, Claude Code's Record-a-Skill, Linus on Linux speed, and how to protect your AI conversations

Aug 17, 2026

I’m David Gewirtz. Welcome to this week’s Advanced Geekery newsletter. It’s been an exciting week. Let’s dive in.

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My latest video

I’m back with a new organizing video. In this quick shot, I show you the filament racks I built, and how they help make room for additional 3D printers.

My articles

Here’s a quick recap of the articles I published in the last week on ZDNET.

Claude’s Record-a-Skill cut my research from hours to 30 minutes - but the magic has limits: I used Claude Cowork to automate a workflow, and the result was remarkably effective, but it exposed four drawbacks.

Claude Code vs. Codex: Why I use both and how to choose one (if you must): Both are astonishingly capable, but subscription choices, coding environments, and hidden ecosystem advantages could make one better for you personally.

75% of developers I surveyed prefer Claude Code - here’s why they choose it over Codex: Three out of four of the 138 developers I surveyed use Claude Code. Here’s what they say matters in daily AI coding workflows.

Must-watch YouTube

Moving on, let’s queue up some interesting YouTube videos for your entertainment and edification.

Linus Torvalds explains why Linux is so quick. But if you listen to him, you’ll also realize that this short clip completely epitomizes what makes Linux so special.
My Internet Press Guild buddy Richi Jennings dug this piece of history up. This is a launch video for OS/2 Warp with Leonard McCoy and Kate Mulgrew. A little bit of context on Mulgrew at the time. At this point, she had been cast in Voyager, but this was before Voyager’s first episode aired. It also represents a strong turnaround in her personal circumstances. She had been in pretty bad financial condition, having had a drought of gigs, a recent divorce, and the expenses of raising two young boys. And then Star Trek.
Good explainer for the Fusion Fillet tool. I learned stuff I didn’t know.

Merch of the week

You saw it in this week’s video. You subscribe to this newsletter. Now you can celebrate your own advanced geekery with this official tee.

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Note: As an Amazon Associate, I earn from qualifying purchases, but not this week.

Interesting reads

And now, some good stuff from around the Internet, well worth checking out.

Apparently, men who drink coffee show higher testosterone levels. And, why yes. I am the alpha in this room.
We know our doggies know our emotional state. Research now shows they’re even more in touch with our feelings than previously thought.
ZDNET’s Lance Whitney explains how to keep your conversations with ChatGPT, Gemini, Copilot or Claude as private as possible.

Send in your projects

I’d like to regularly spotlight a reader project or two here. Your project doesn’t have to be a big Kickstarter launch. If you’ve built something cool, it has some pretty pictures, and you’re proud of it, I might be able to share it here.

If you have a photogenic reader project, send an email to me at david@zatz.com with the subject “READER PROJECT,” a few pictures, and a short one-paragraph description. If you have a social media link or a link to the project, include that, too.