I'm Sergio, a software engineer building useful tools, small experiments, and things I want to use. Usually with a coffee nearby.
Press Escape to turn the lights back on.
Fresh cup. First sip’s the best.
Many bags of coffee code to choose from.
01 / WORK
WORK / SELECTED Lead UI architect for Great Clips' mobile-first web app, serving 2.5M+ users a month on Next.js/React SSR, and lead backend engineer for its Live Activities microservice serving 5M+ users across iOS, Android, and web.
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WORK / SELECTED Led a 6-engineer UI team, mentoring its other 5 engineers, for an internal A/B testing platform used across Target.com and its iOS/Android apps, testing variations on 50M+ users a month.
WORK / SELECTED Co-founded Pericle, a board game published by Long Dog Games, and was its lead full-stack engineer, the sole engineer on the companion web app (pericle.app) that runs the game's 100+ hour campaign.
Visit project ↗02 / PERSONAL
PERSONAL / SELECTED A tier list of coffee, wings, N/A beers, reubens, and maple syrup, statically prerendered with TanStack Start against Sanity content.
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PERSONAL / SELECTED A solo-built "make exact change" calculator for Elden Ring that tells players the optimal Runes to spend on an upgrade without overshooting.
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PERSONAL / SELECTED A solo-built desktop app (Electron/React/TypeScript/SQLite) for timed group workouts. It tracks each person's max weights, calculates the day's working weight, and switches exercises on a timer so several people can train together.
Visit project ↗A little flight through my professional life.
Engineer
Refactored the team's codebase to higher coding standards, built out REST endpoints, and rewrote the Angular frontend, while mentoring developers and establishing an end-to-end testing practice.
Senior Engineer
Combined hands-on UI work with mentoring five engineers, teaching testing practices, and presenting UI fundamentals to 650+ engineers each year.
Co-founder and Lead Full-Stack Engineer
Owned the product's UX design alongside its engineering, working through video playback, authentication, caching, and optimistic updates while using feedback to guide improvements.
Senior Engineer
Serves as lead engineer for the Great Clips web app, owning component architecture and engineering standards while mentoring engineers and sharing practices through twice-monthly talks on agentic engineering and AI ethics.