Leonardo Maldonado

I'm Leonardo. I grew up in Franca, Brazil and moved to Valencia, Spain a few years ago. I wanted to be closer to the European tech scene and, honestly, I just really like it here. The weather, the food, the pace of life.

I've been writing code for about 7 years now. Most of that time was spent at Namecheap, where I was the sole engineer on Spaceship's domain search. I built the whole thing from zero and helped the platform sell 3M+ domains: the architecture, the real-time pricing over WebSocket, bulk search, multi-currency support across 30+ currencies. Four and a half years of owning a product end to end.

On the side, I've built a few things I'm proud of. Shopwyse is a retail ERP I built full-stack with TanStack Start and PostgreSQL. Polyglot is an AI writing tool that interviews you before drafting anything. Otis Finance is a stock market API. I also write CLI tools in Go and Rust when I want to learn something new by solving a real problem.

In 2018, I made 33 JavaScript Concepts. It was supposed to be a personal study guide, but it took off. 66K+ stars now, translated into 40+ languages. GitHub named it a top project of 2018. I still maintain it.

I also spent a few years writing for Progress and LogRocket. 100+ articles on JavaScript, TypeScript, React, Node.js, GraphQL. Over a million views total. I like explaining things clearly and helping other developers learn.

My main stack is TypeScript, React, and Node.js, but I don't treat tools like an identity. I pick whatever gets the job done. Go and Rust for side projects, PostgreSQL for data, whatever framework makes sense for the problem.

When I'm not coding, I'm probably walking around Valencia, reading, or tinkering with a side project that may or may not ship. I speak Portuguese, English, and Spanish.

If you want to chat, I'm always up for it. Send me an email or find me on X.