Ten years ago, programming meant typing code into a blank word processor and editing it manually. But with the advent of generative AI, this type of programming is quickly becoming a thing of the past, he explained.

“More and more, you can take a step back from the code, and you can ask an AI to go do end-to-end tasks for you,” Truell said at the Fortune Brainstorm AI conference in December. 

Yet programmers may not want to step back too far, he added, pointing out that there are levels to AI-assisted coding. 

What is vibe coding?

The oft-repeated term “vibe coding” may seem to encapsulate all AI coding assistants. In reality, it suggests amateur builders or inexperienced AI users trying to bring an idea to life without necessarily looking under the hood.

“Vibe coding refers to a method of coding with AI where you kind of close your eyes, and you don’t look at the code at all, and you just ask the AI to go build the thing for you,” he said.

Truell likened it to building a house by putting up four walls and a roof without knowing what’s going on under the floorboards or with the wiring.

This coding method may be perfect for AI users looking to quickly mock up a game or website, but when it comes to more advanced programming, things have the potential to go wrong, he warned.

“If you close your eyes, and you don’t look at the code, and you have AIs build things with shaky foundations as you add another floor, and another floor, and another floor, and another floor, things start to kind of crumble,” he said. 

How Cursor differs—and why it matters

With Cursor, by contrast, programmers can embed AI directly into the integrated development environment where programmers write their code. By using the context of the existing code, or even an entire code base, it can often predict the next line. The tool includes everything from multi-line-autocomplete to full function generation. It can also help a programmer debug their code and explain errors.

Despite being only 25 years old, Truell’s take on AI coding carries real weight. He and three other graduates from the Massachusetts Institute of Technology created what would become Cursor as a project in 2022.

Since then, Cursor has become one of the most popular coding assistants out there, with more than 1 million daily users as of last year, Bloomberg reported. Since it launched, the company has reached $1 billion in annualized revenue and amassed 300 employees, according to CNBC.

Cursor received its first $8 million investment from OpenAI’s Startup Fund in 2023. It later raised more millions from some of the biggest venture capitalists in Silicon Valley, including Andreessen Horowitz. In 2025, the company closed on a $2.3 billion funding round at a $29.3 billion post-money valuation. Finally, as of this month, Bloomberg noted Cursor was reportedly in the process of a funding round that would value it at about $50 billion.

While vibe coders may be flying blind, Truell said the Cursor coding assistant is the best of both worlds, helping its expert customers get into the nitty-gritty details of their code.

“But then in the places where you want to take a step back and you want to ask the AI to do something end-to-end you can do that, too,” he said.

A version of this story originally published on Fortune.com on Dec. 25, 2025.

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