Gustavo Santos
I'm a software engineer. I build interfaces in React, React Native and TypeScript, and I
care about what sits underneath them: code that reads well, tests you can trust and
products that are simple to use. When a problem of mine has no tool, I write one; that is
how Marmita and Subagent City started.
Experience
Software Engineer
2022 – present
Defined.ai
- Maintain and evolve a product used by more than 2.1 million people.
- Built Diana, a multilingual conversational AI experience launched at Web Summit.
- Built a design system and component library for a micro-frontend architecture.
- Led the migration of the corporate website from Magento and WordPress to Next.js.
- Raised test coverage by 63% and drove the move from Enzyme to React Testing Library.
- Moved mobile CI/CD from App Center to Azure DevOps and removed secrets from the codebase.
- Mentored three developers early in their careers.
Software Engineer Intern
2022
Eyecon Group
Gathered requirements and built a TypeScript product backed by MongoDB.
Projects
A zone-based window manager for macOS. Drag a window with Shift held, the zones appear on screen, and the window snaps into the one you drop it on.
Swift, AppKit, SwiftUI
A live map of the Claude Code subagents running on a machine: who started each one, what it is doing and which model it runs on.
TypeScript
Household chores logged with a tap on an NFC tag, with reminders by push notification.
Next.js, PWA
A mobile app for pet owners, a web platform for vets and the REST API behind both, designed and built end to end.
React Native, Node.js, Firebase
Education
BSc in Computer Science
2026 – present
IADE, Universidade Europeia
Vocational Diploma in Computer Programming
2020 – 2022
FEPPV
Awards
2nd place, WorldSkills Portugal
2021
Vote of congratulation from the Legislative Assembly of the Azores
Skills
- Front-end
- React, React Native, Next.js, TypeScript
- Testing
- React Testing Library, Jest, Vitest, Playwright
- Back-end
- Node.js, REST, MongoDB, Firebase
- Tooling
- Git, Docker, Azure DevOps
- Languages
- Portuguese, English (Cambridge B2 First)