Welcome to Full Stack Friday, serving up the hottest AI developments fresh off the griddle, specifically for AI builders. We've got 2298 (🔥) new subscribers since the last send – welcome to the stack! 🥞

Big week in the coding agent world. The tools you use every day started picking sides. If you're building with AI, you need to know what happened. I’ll break down the shakeup, Cursor's big upgrades, and a ton of quick hits.

I'll keep this snappy so you can finish this before your pancakes get cold (I assume you're eating pancakes).

Here's what we're covering:

Let's do this.

When I say I use Claude Code all day every day, that means I'm also using:

Nimbalyst → the best way for PMs to use Claude Code.

Here's the problem: Claude Code runs in terminal. Which means your options are:

Nimbalyst fixes this. You can edit files with formatting directly. It's what Claude Code should feel like for people who work in documents, not code.

And it's completely free. If you have some spare time, my Claude Code for PMs course can be completed in about 5 hours and works perfectly in Nimbalyst.

Last week I mentioned that Cowork was released, that I was kind of a hater, and I'd consider going deeper once it was more generally available. Well — right after I sent that email, Anthropic announced it was available to all Pro users ($20/mo).

So I gave it a deep dive. And... it's okay. It's a lot more powerful than a browser-based chatbot, but it's still a far cry from Claude Code.

If the terminal is still too daunting for you, definitely give Cowork a try. You'll start to get a sense of why an on-device LLM is so much more powerful than one in the browser, and hopefully it serves as your gateway to becoming fully Claudepilled.

Building off my trademark "tool-in-tool" courses, I made a complete guide to Cowork that you do in Cowork. I gave the guide a faithful effort. Honestly it's really good 💅

I hosted a "Claude Code: Zero to Pro" event with Product Faculty this week. Over 6,500 signups and over 1,100 people live, officially breaking Product Faculty's record as the biggest live event they've ever hosted!

I made the session fully interactive:

People loved it but there was some feedback that I went kind of FAST 😅 So it's probably better as a recording anyway. It is similar material to what I cover in my (free & interactive) Claude Code for PMs course, but it’s a good session if you want to have the information presented and see what it looks like when I actually use it.

I forgot to mention in my last send — I recently launched Product in Seattle to help revive Seattle's product scene. If you live here, join the list for monthly updates about upcoming events! You can submit your own.

Last night I hosted the biggest Lenny's Meetup in Seattle history, in large part because I featured it in this newsletter. Over 100 people, which is huge for this sleepy city.

And next month I'm hosting my first event as Seattle's official Cursor ambassador – A Fully interactive live workshop: Cursor for PMs. Check it out!

If you are interested in setting something up like this your city, let me know. I am working on templatizing this.

These votes heavily influence my content roadmap. I really just want to build what you all want to learn.

Connecting your AI to everything (MCPs & APIs) module coming next week!

Onto the stories.

On January 5-9, Claude Code started blocking third-party tools from using Max subscription tokens. No warning. OpenCode (56k GitHub stars), Cursor configs, and a bunch of other tools broke overnight. DHH called it "very customer hostile." This HN thread blew up.

Here's what happened: if you pay for Claude Max ($200/month), you get practically unlimited Claude tokens, but those tokens only work through Claude Code. Third-party tools like OpenCode had been spoofing Claude Code's client identity so users could get their Max tokens through a different interface. Same subscription, different app. Anthropic shut it down, saying the spoofing caused technical issues they couldn't debug.

If you use Claude Code directly, this doesn't affect you at all. You're still getting the best value in AI coding — $200/month for usage that would cost $1,000+ through the API. The people who got burned are the ones who wanted Claude's model through a different tool's interface.

The counter-moves were fast: GitHub officially partnered with OpenCode (your Copilot subscription now works with it), and OpenCode shipped ChatGPT Plus support within hours.

The bigger picture: Claude Code is amazing value but it locks you to one model. Cursor costs more for heavy usage but works with Claude, GPT, Gemini — your choice.

Worth thinking about as you pick your tools. Speak of which…

Tools like Claude Code, Cursor, and Codex CLI are “harnesses” — wrappers that determine how effectively a model works. The model is the engine, the harness is the car. Claude Code won because the harness is incredible. Other harnesses have been way behind. These Cursor updates are them closing the gap.

Two releases in one week:

CLI Update (Jan 16):

Cursor 2.4 (Jan 22):

Cloud Handoff is the standout. Start debugging on your laptop, push to cloud, continue from your phone. Nobody else has this.

Once you start using tools like Claude Code, the temptation to keep building your system rather than building actual things hits you pretty fast.

I loved these memes this week:

Quick hits that matter for AI builders. Stuff you can actually work with right now.

If you only have 30 minutes this week and you’re a Cursor user, install Cursor CLI and try the & prefix to push a task to cloud. It’s pretty amazing.

Keep building,
Carl