Location: Mar del Plata, Argentina (UTC-3) Remote: Yes Willing to relocate: No Technologies: Ruby on Rails, JavaScript, React, PostgreSQL, Hotwire, AI coding

Location: Mar del Plata, Argentina (UTC-3) Remote: Yes Willing to relocate: No Technologies: Ruby on Rails, JavaScript, React, PostgreSQL, Hotwire, AI coding agents Résumé/CV: https://smarquez1.github.io/assets/Sergio-Marquez-Resume.pdf https://smarquez1.github.io/assets/Sergio-Marquez-Resume.pdf Email: marquez.sergio.d@gmail.com Website: https://smarquez1.github.io/ https://smarquez1.github.io/ I'm a product-oriented software engineer with 15+ years of experience building web applications, mostly with Ruby on Rails and JavaScript. I work directly with clients and users to understand their workflows, discuss tradeoffs, and turn those conversations into useful product decisions. I communicate comfortably in English with clients and distributed teams. I've worked full stack across backend systems, APIs, React, performance, testing, and product discovery. In a previous role, I reduced page-load times by 20% to 80%, cut CI runs from roughly 40 minutes to 8, and led the modernization of more than 500,000 lines of Rails code. For the past two years, I've also used Claude and Codex as coding agents for implementation, research, code review, documentation, and product design. I still review and test everything before it ships. I'm looking for a remote Senior Product Engineer or Senior Software Engineer role, preferably with Rails, but also open to full-stack React and JavaScript work. I'm particularly interested in teams building AI-native products or improving how engineers use coding agents.