What is the 42 network?

That was the question a group of entrepreneurs and executives asked me when they found out I had studied there.

Most people know École 42, the global coding school founded by French billionaire Xavier Niel, famous for its project-based learning and peer-to-peer approach, entirely without traditional teachers.

So I turned the question back to them: "If that's the essence of 42, what else do you need to know?"

They were intrigued by 42's innovative and disruptive learning system. In just five years it climbed from 17th (2020) to 6th in the Global Top 300 Innovative Universities of the World University Rankings for Innovation (WURI), surpassed only by MIT and Stanford University.

Many questions came up, but they clustered around four curiosities. I adapt my answers here.

First curiosity: is 42 only for software engineers?

At 42 Madrid Fundación Telefónica I've met many people who don't come from engineering, and it's fascinating.

I know a young lawyer, once used to paperwork, who now masters Git and Linux. Also an Art Dealer & Curator, two philosophers, a historian and political scientist who recently defended his PhD, a digital marketing expert, a dentist, three psychologists and several artists — including a photographer, a painter and a skateboarder.

Why do they study at 42? Among other reasons, because they understand the need to master new tools for their life, their business or their profession.

Second curiosity: is 42 only for young people on a gap year?

I don't have the exact statistic, but I've met more than thirty people at 42 over 45 years old. Time management is a real challenge. I know, for example, a CEO who makes time to attend and learn at 42, delegating tasks to her team even while she's constantly interrupted by messages.

Third curiosity: isn't studying C obsolete?

I used to think the same. But once I dove in, I started to understand and appreciate the purpose of each language.

Think about it: DeepSeek AI uses PTX programming, similar to assembly. In essence, they leveraged machine language to get better performance at lower cost than companies like Anthropic or OpenAI. At 42 Madrid there's a cadet mastering these low-level languages with the goal of optimizing complex AI workloads.

Fourth curiosity: is it worth it?

On the technical side, 42 appears in the WURI Top 100 Funding (B2): among the world's 100 best-rated universities for funding and financial management — which is what lets them keep tuition free.

But look at it from another angle: the level of rigor cadets must clear to complete every 42 challenge is exactly what makes them valuable hires for your companies, because they'll bring meaningful value to your business.

I recently had the chance to meet Sophie Viger, Managing Director of 42, during her visit to Madrid; and Luis Prendes, General Director of Fundación Telefónica, whose excellent stewardship of the four 42 campuses in Spain I'm grateful for.

Personally, I consider 42 Paris one of the most significant events of my life. The first six months were a real struggle to push every project through, but a crucial lesson came from a staff member known by the pseudonym YZMA: "Don't focus only on whether each function works correctly; try changing an argument in every possible way and observe its behavior." That advice was invaluable during my Freezer period.