Garry Tan, Y Combinator’s famous CEO, told an audience at SXSW that he suffers from “cyber psychosis” and is so excited about working with AI agents that he can barely sleep.
“I’m sleeping about four hours a night now,” he told fellow interviewer VC Bill Gurley in an on-stage interview Saturday. “I have cyberpsychosis, and I think a third of the CEOs I know suffer from it as well,” he joked about his current obsession with AI. (At least, I hope he was kidding. AI-induced psychosis may actually be a dangerous condition.)
“Once you try it, you’ll understand. It’s like being able to rebuild your startup with $10 million in venture capital, 10 people, working on it for two years, taking an anti-narcolepsy drug. I remember it being like taking Modafinil,” he explained, referring to the sleep-disrupting drug popular with the startup hustle culture crowd. (Tan sold Y Combinator-backed blogging startup Posterous to Twitter in 2012.)
But now his mind is so amplified by working with an AI agent that he becomes a natural insomniac.
“We don’t need modafinil in this revolution. I’m already awake. I went to bed at 4 a.m. and woke up at 8 a.m.,” he said. “I would have liked to have slept more, but I couldn’t. Look what’s going on with my 10 employees. I have about three different projects going on right now.”
He was so excited about his agent that on March 12th, just two days before the interview, he proudly shared his Claude Code (CC) setup freely on GitHub under an open source license. This setup included six “unique” Claude code skills that he developed. Skills are reusable prompts stored in a special “skill.md” file that instruct the AI on how to perform a specific role or task.
“I’ve had such a great time with Claude Code, I wanted to be able to have my *exact* skill setup,” he posted on X. He called his Claude code setup “gstack”.
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Since then, he has added a few more skills. The gstack GitHub repository currently has 13 listed, but Tan seems to be tweeting about something new every hour.
In one post, he gave an example of how the setup works. First, use Claude’s Acting Like a CEO skill to get Claude’s opinion on whether the startup’s idea or feature is a good idea. He uses another skill to have Claude create features as an engineer, and another skill to review his work for bugs and security issues as a code reviewer. Other skills include design, documentation, etc.
My love for gstack started quickly. His tweet went viral on X and trended on Product Hunt. There are 2,200 “forks”, or people who have taken the files and modified them themselves, on GitHub, accumulating nearly 20,000 stars.
However, shortly after releasing gstack, Tan posted a tweet that sparked heaps of hate.
He wrote that a CTO friend told him that gstack was in “god mode” for instantly discovering security flaws in the company’s code and predicting widespread use.
To quote just a few of the many hateful comments that followed, one founder posted on X: “(1) Garry who tweeted this should be ashamed. (2) If that’s true, that CTO should be fired immediately.”
Video blogger Mo Bitar wrote an article about gstack titled “AI is making CEOs paranoid,” noting that the project is essentially “a bunch of prompts” in a text file. This vlogger summed up the common complaints. Developers using Claude Code already have their own version.
Added 1 person to Product Hunt. “Garry, let’s be blunt and honest: If you weren’t the CEO of YC, this wouldn’t be on PH.”
So who is right? Is gstack a unique and convenient way to work with Claude code, or is it unobtrusive? To find out, I asked experts, including Claude (who, unsurprisingly, loved this piece). I also contacted ChatGPT and Gemini, both of which had surprisingly positive results.
Gstack is “a fairly sophisticated group of prompting workflows, but it’s not ‘magic,'” says ChatGPT. “The real insight here is that AI coding works best when it simulates the structure of an engineering organization. It’s not when you just say, ‘Build this feature.'”
Gemini called the setup “sophisticated,” adding, “gstack is essentially a ‘Pro’ configuration. It’s less about making it easier to code and more about getting your code right.”
Claude called gstack “a mature, proprietary system built by people who actually use it frequently,” adding, “It’s one of the better examples of Claude code skill design out there.”
I will accept this as a positive opinion from an expert on this matter.
On Monday, Tan wrote in another X post, “I took Modafinil to help me stay awake longer just to turn the temporary crystal structures in my brain before sleep into lines of code, or human distractions into grains of sand. I love coding, but I love coding with AI even more. We speak, we hear, we create. I see structure, it builds. There has never been a more powerful experience for me.”
Mr Tan did not respond to multiple requests for comment.
