Famous Y Combinator CEO Garry Tan said in one SXSW crowd that he has “cyber psychosis” and barely sleeps because he’s so excited about working with AI agents.
“I’m sleeping four hours a night right now,” he told his interviewer, fellow VC Bill Gurley, during an onstage interview Saturday. “I have cyberpsychosis, but I think a third of the CEOs I know have it too,” he joked about his current obsession with artificial intelligence. (At least, we hope he was joking. AI-induced psychosis can actually be a dangerous condition.)
“Once you try it, you’ll realize: It’s like I was able to recreate my startup that took $10 million in VC capital and 10 people, and I worked on it for two years and I was on anti-narcotics — I remember, you know, I kind of take Modafinil,” he described, referring to the popular sleep-prevention drug startup. (Tan sold Y Combinator-backed blogging startup Posterous to Twitter in 2012.)
But now, his soul is so enhanced when working with AI agents, that he is a natural insomniac.
“I don’t need modafinil with this revolution. Like, I’m awake. I went to sleep at 4 in the morning, woke up at 8 in the morning,” he said. “I wanted to sleep more, but I couldn’t because: Let’s see what happens with the 10 workers. I have like three different projects running right now.”
He’s so excited about his agents that on March 12th, just two days before the interview, he proudly shared the Claude Code (CC) setup freely on GitHub under an open source license. The setup included six Claude Code skills that he developed with “view”. Skills are reusable messages stored in special “skill.md” files that instruct the AI how to behave in specific roles or tasks.
“I’m having a great time with Claude Code, I wanted you to be able to have my *exact* skill set,” he said. posted on X. Name the Claude Code setup “gstack”.
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Since then he has added many more skills. The gstack GitHub repository currently contains 13, but it seems like every hour Than tweets for something new.
In a post, he gave an example of how his setup works. First, he gets Claude’s opinion on whether a startup idea or feature is a good idea using a skill where Claude acts like a CEO. He uses another skill to write Claude the feature as an engineer, and another to check his work for bugs and security issues as a code reviewer. Other skills cover design, documentation and so on.
The love for gstack started immediately: His tweet went viral on X and trended Product hunt. It has accumulated nearly 20,000 stars on GitHub with 2,200 “forks,” meaning people who have taken the files to modify them themselves.
But shortly after the release of gstack, Tan posted a tweet that also caused a lot of hate.
He wrote that a CTO friend told him gstack was “god mode” that immediately found a security flaw in his company’s code and predicted it would be widely used.
To name just a few of the many hateful comments that followed: A founder published in X: “(1) Garry should be ashamed for tweeting this. (2) If true, this CTO should be fired immediately.”
Vlogger Mo Bitar took a shot in gstack called “Artificial Intelligence Makes CEOs Delusional” in which he pointed out that the project was essentially “a bunch of prompts” in a text file. The vlogger summed up the common complaint: Developers using Claude Code already have their own versions of it.
Added a person to Product hunt“Garry, let’s be clear and honest: if you weren’t the CEO of YC, this wouldn’t be in PH.”
So who is right? Is gstack a uniquely useful way to work with Claude Code? Or trivial? To find out, I asked the experts, including Claude (who, unsurprisingly, absolutely loved it). I also asked ChatGPT and Gemini, which were surprisingly positive.
Gstack is a group of “reasonably sophisticated workflows, but they’re not ‘magic’,” ChatGPT said. “The real picture here is that AI coding works best when you’re simulating a mechanical organism structure. Not when you’re just asking: ‘build this feature.’
Gemini called the setup “sophisticated,” adding that “gstack is essentially a ‘Pro’ configuration. It’s less about easier coding and more about correct debugging.”
Claude called gstack “a mature, system-driven system built by someone who really uses it a lot,” adding, “It’s one of the best examples of Claude Code design skills out there.”
We’ll take it as an endorsement from a subject matter expert.
On Monday, Tan explained to another X post“I took modafinil just to stay awake longer so I could turn the momentary crystal structures I had in my brain into lines of code before I fell asleep or human distraction turned it into grains of sand. I love coding, but I love coding with artificial intelligence even more. I talk and listen and we create. I see the structure and it’s built. There is no more powerful experience for me.”
Tan did not respond to multiple requests for comment.
