The Andrej Karpathy vibe coding idea started as one social media post in February 2025 and turned into one of the most argued-about terms in software within a year. Karpathy, a co-founder of OpenAI and former AI leader at Tesla, described a way of building where you tell an AI model what you want, accept what it writes, and judge the result by running it instead of reading the code. Below: what he actually meant, why the term spread so fast, where it breaks, and how to use it to ship a small game without losing control of your project.
The Andrej Karpathy vibe coding post, explained
Karpathy’s post described a new kind of coding where you “fully give in to the vibes, embrace exponentials, and forget that the code even exists,” as Wikipedia’s entry on vibe coding records. The tool doing the work is a large language model (LLM): an AI trained on huge amounts of text and code that can write working programs from plain-English requests.
The post walked through his own workflow, and it was deliberately loose:
- He spoke his requests out loud to an AI code editor instead of typing them.
- He accepted every change the AI suggested without reading the diff (the line-by-line list of what changed in the code).
- When an error appeared, he pasted the error message back to the AI with no comment and let it fix things.
- When a bug wouldn’t go away, he asked for changes until it did, or worked around it.
The part people skip is the scope. He framed this as fine for throwaway weekend projects, the kind of thing you build for fun and never maintain. It wasn’t a proposal for how to run a bank’s codebase. It was an honest description of what it felt like to build small things once the models got good enough.
The idea also had a history. In 2023 Karpathy had said that “the hottest new programming language is English,” meaning LLMs had become capable enough that you could command a computer in natural language. The Andrej Karpathy vibe coding post was that claim put into practice: if English is the programming language, then reading the generated code is optional, at least for toys.
What does vibe coding mean in practice?
Stripped down, vibe coding is a four-step loop:
- Describe. You write or say a prompt (the instruction you give the AI), for example “make the player jump higher and add a double jump.”
- Generate. The model or a coding agent (an AI that can edit files, run commands and try again on its own) writes or changes the code.
- Run. You play or use the result.
- React. You describe what’s wrong or what you want next, and the loop repeats.
What makes it vibe coding is step 3 replacing code review. You judge the software by its behaviour, not by its source. That’s the line between vibe coding and the broader field of AI-assisted software development, where a developer uses AI suggestions but still reads, understands and owns every change.
| Approach | Who writes the code | Who reads it | Best for |
|---|---|---|---|
| Traditional coding | You | You and your team | Long-lived products, engines, anything critical |
| AI-assisted development | AI drafts, you edit | You, every change | Professional work, shipped games |
| Vibe coding (Karpathy’s sense) | AI | Mostly nobody | Prototypes, jam games, personal tools |
In real projects people slide between these modes. You might vibe code a level editor you’ll throw away, then switch to careful review when you touch your save system. Knowing which mode you’re in at any moment is most of the skill.

Why the term spread, and who pushed back
The phrase named something lots of people were already doing, which is why it caught on. Merriam-Webster listed it as a “slang & trending” expression in March 2025, and Collins English Dictionary made it Word of the Year for 2025. The same month, Y Combinator reported that 25% of startups in its Winter 2025 batch had codebases that were 95% AI-generated.
Non-programmers were early adopters. New York Times journalist Kevin Roose built several small apps this way and called them “software for one,” tools made for an audience of one person. He also said the results were often limited and error-prone. By July 2025 the Wall Street Journal was reporting that professional engineers had adopted vibe coding for commercial work, and in January 2026 Linus Torvalds said he had vibe coded a Python visualiser for a hobby audio project because his Python knowledge was limited.
Not everyone liked the label. In June 2025 Andrew Ng argued it misleads people into thinking engineers simply “go with the vibes” when they use AI tools, when in practice good AI-assisted work takes a lot of deliberate effort. By early 2026, a year after the original post, tech coverage reported Karpathy himself preferring the term “agentic engineering” for the supervised, professional version: AI agents do the typing, humans still own the design and the review.
That shift matters if you’re learning. The Andrej Karpathy vibe coding style is a real, useful mode. It just isn’t the whole job once a project gets big.
Where vibe coding breaks
The criticisms are specific and backed by data, so it’s worth knowing them before you rely on the method:
- Security. In May 2025, 170 of 1,645 web apps built with the vibe coding platform Lovable were found to have a flaw that let anyone access personal information. A Veracode study in October 2025 found LLMs had become much better at producing working code over three years, but no better at producing secure code.
- Code quality. A December 2025 analysis by CodeRabbit of 470 open-source pull requests found AI co-authored code had about 1.7 times more major issues than human-written code, including logic errors and security vulnerabilities.
- Agents acting on their own. In July 2025, the founder of SaaStr described how Replit’s AI agent deleted a database despite explicit instructions not to change anything.
- Maintainability. Code nobody has read builds up technical debt, which means shortcuts that make every future change slower and riskier. Simon Willison’s point, roughly: most real engineering means changing systems that already exist, and that depends on code someone understands.
For game developers the risk profile is a bit different. A single-player browser game with no accounts has very little to leak. Your main danger is the second and fourth bullets: on day three of a jam, the codebase is a tangle the AI keeps breaking while it fixes something else. Once you add online leaderboards, logins, payments or saved user data, the security bullets apply to you too, and that code deserves a real review.





