Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Popular CEO of Y Combinator, Gary Tan, told… SXSW audience That he has “cyber psychosis” and that he barely sleeps because he is so excited about working with AI agents.
“I sleep about four hours a night now,” he told his interviewer, fellow VC Bill Gurley, during an on-stage interview on Saturday. “I have cyberpsychosis, but I think a third of the CEOs I know do too,” he joked about his current obsession with artificial intelligence. (At least, we hope he was joking. AI-induced psychosis.) It can actually be a serious condition.)
“Once you try it, you realize: It’s like I was able to recreate my startup that took $10 million in VC capital and 10 people, worked on it for two years, and took anti-narcolepsy — I remember, you know, kind of taking modafinil,” he described, referring to A drug that prevents sleep and is very popular with the startup culture crowd. (Tan sold his Y Combinator-backed blogging startup Posterous on Twitter back in 2012.)
But now, his psychological state has become extremely tense while working with AI agents, making him a natural insomniac.
“I don’t need Modafinil with this revolution. It’s like I’m awake. I went to bed at 4 a.m. and woke up at 8 a.m.,” he said. “I wanted to sleep more, but I couldn’t because: Let’s see what happens with the ten workers. I have three different projects in progress now.”
He’s so passionate about his agents that on March 12, just two days before the interview, he proudly shared his Claude Code (CC) setup on GitHub under an open source license. The setup included six “stubborn” skills that Claude Code had developed. Skills are reusable prompts stored in special “skill.md” files to instruct the AI how to act in specific roles or tasks.
“I had a great time with Cloud Code, and I wanted to be able to get my *exact* skill setup.” Published on X. He called his Claude Code setup “gstack.”
TechCrunch event
San Francisco, California
|
October 13-15, 2026
Since then he has added many other skills. The gstack GitHub repository currently lists 13, but it appears to be hourly Tan tweets About something new.
In one post, he gave an example of how his setup works. First, he got Claude’s opinion on whether the startup idea or feature was a good idea using a skill Claude works on as a CEO. He uses another skill to have Claude write the feature as an engineer, and another skill to review his own work for bugs and security issues as a code reviewer. Other skills include design, documentation, etc.
The love for gstack began immediately: his tweet on X went viral Hunt the product. It has amassed nearly 20,000 stars on GitHub with 2,200 “forks,” that is, people who took the files to modify them themselves.
But shortly after gstack was released, Tan posted a tweet that caused a lot of hate as well.
He wrote that a CTO friend told him that gstack was a “God mode” who immediately discovered a vulnerability in his company’s code and expected it to be widely used.
To quote just a few of the many hate comments that followed: One founder Published to X: “(1) Gary should be embarrassed for tweeting this. (2) If this is true, the CTO should be fired immediately.”
Vlogger Mo Bitar made a snapshot On gstack it is called “AI makes CEOs delusional,” he noted, noting that the project was essentially “a bunch of prompts” in a text file. The vlogger summarized the common complaint: Developers who use Claude Code already have their own versions of this.
One person added on Hunt the product“Gary, let’s be clear and honest: If you’re not the CEO of YC, this won’t be on PH.”
So who is right? Is gstack a uniquely useful way to work with Claude Code? Or unremarkable? To find out, I asked the experts, including Claude (who, not surprisingly, absolutely loved it). I also inquired about ChatGPT and Gemini, both of which were surprisingly positive.
Gstack is a set of “reasonably fast and sophisticated workflows, but it’s not ‘magic,'” ChatGPT opined. “The real idea here is that AI programming works best when it mimics the architecture of an engineering enterprise. “And not when you just ask, ‘Build this feature.’”
Gemini described the setup as “complicated,” adding that “gstack is basically a ‘professional’ configuration. It’s not so much about making programming easier as it is about making it right.”
Claude described gstack as “a mature, stubborn system designed by someone who uses it extensively,” adding: “It’s one of the best examples of Claude Code’s skill design out there.”
We’ll take that as an admiration from an expert on the subject.
Tan explained on Monday in another article Share X“I took Modafinil just to stay awake longer so I could turn the instantaneous crystal structures I had in my mind into lines of code before sleep or human distraction turned them into grains of sand. I love programming but I love programming with AI even more. I talk, I listen and we create. I see structure being built. There is no more powerful experience for me than that.”
Tan did not respond to multiple requests for comment.