Javier S.

Fullstack engineer based in Madrid, with a strong frontend foundation and over 10 years of experience building web products — from the early days of SPAs to today's server-first renaissance.

I started with JavaScript when component-based, client-side rendering felt like the future. I've since lived through the full arc: the rise of SPAs, the over-engineering that followed, and the return to SSR. That journey gave me a healthy skepticism toward hype and a genuine respect for fundamentals (the kind that compound over time).

Currently applying that perspective to the decentralized/web3 space, where the gap between good engineering and "it works in a demo" is especially wide.

How I work:

I care about the whole flow, not just the code. That means thinking about how Agile is actually practiced on a team, how CI/CD pipelines are designed to give developers real confidence, and how a solid testing strategy (shaped by the testing pyramid) makes refactoring and shipping fast features feel safe rather than scary. I'm a strong advocate for pair programming and code reviews as tools for alignment, not gatekeeping.

On the AI side: I've been integrating AI tooling into my workflow progressively since 2022 (from GitHub Copilot to Cursor to Claude Code) and have adopted spec-driven development practices (OpenSpec) as part of day-to-day engineering. I treat AI as a force multiplier for experienced engineers who already know what they're building.

Strong in: React ecosystem, TypeScript, Node.js, frontend architecture.