Wandering through ideas
What I'm focused on right now.
Building Onda: AI and data systems for SMEs. We build a company's data layer and the AI on top of it, then teach the team to run it. Live in fuel distribution, M&A advisory and education since 2026.
The work is putting analytics and AI agents where decisions actually get made. What I care about is whether the thing is still running six months after I leave. A pilot nobody uses is not a result.
Training Brazilian jiu-jitsu, sitting Vipassana, and learning to think in public. This site is the first move.
Client work stays private. More here when there's more I can show.
I'm Arnau, a data-driven builder based in Barcelona.
I work at the intersection of data analytics, AI orchestration, and first-principles thinking. My path went from consulting at Deloitte to running data + AI inside an e-commerce supplements startup, and in 2026 to founding Onda.
What I'm good at is a rare pairing: the technical side (Python, SQL, dbt, agent orchestration) and the human side (persuasion, teaching, turning complexity into decisions). I build for leverage: high-value systems for a solo operator, not boilerplate for a team of ten.
Off the screen: Brazilian jiu-jitsu, traditional yoga, qigong, meditation, and surf. I optimise around sleep and around freedom, temporal and financial.
I believe authenticity beats performance, that depth beats breadth, and that most things are better reasoned from first principles.
Longer writing. Infrequent, high quality.
More essays coming.
Ideas I keep coming back to. Open one.
Language is the foundation of human power
Humans became the dominant species not because of strength, but because of language. Everything we've built, religions, laws, money, nations, is ultimately made of words. Now, for the first time, something non-human (AI) may become better with words than we are.
The real bottleneck is wisdom, not intelligence
AI makes intelligence cheap and abundant: the “genie” that can grant any wish. But fairy tales warn us: people usually wish for the wrong things. Intelligence solves problems; wisdom chooses which problems are worth solving.
AI is not a tool, it's an agent
A printing press or an atom bomb can't decide anything on its own; humans decide. AI is different: it can make decisions and invent new things by itself. That's what makes it unprecedented in history.
We may end up like horses in the financial system
Horses' lives are controlled by markets they can't even perceive. As AI makes finance and governance impossibly complex and fast, humans may similarly live inside systems no human being understands at all.
These four came out of Yuval Noah Harari's talk The next 50 years: humanity, AI, power (July 2026). The framing is his; keeping them here is mine.
A running list of what shaped how I think.
Music I return to, and soon podcasts and audio worth your time.
Audio coming soon.
Steph Ango: file-over-app, evergreen notes.
nownownow: the /now page movement.
People and things worth your time.
Barcelona, GMT+1. The best way to reach me is email.