Matheus Q.

• Led the Streak Calendar gamification feature from an AI-hackathon prototype to full production in about six weeks, for an app with about 7.2M users. I put together and led a cross-functional team and owned engineering from the React Native client to the backend integration.
• Treated AI-generated code as a starting point, not as finished work. I hardened the prototype with typed contracts, edge-case coverage, accessibility, localization into 12 languages, and a staged 1% → 5% → 10% → 100% rollout behind feature flags, with a kill switch and A/B testing.
• Designed a GraphQL BFF layer (Node.js/Apollo) that combined several over-fetching calls into one typed query. I also built a server-authoritative streak engine with per-request timezone handling, and integrated APIs from several squads.
• Built a POC of GitHub Copilot custom instructions that steer AI code suggestions toward the design-system standards. I also brought AI-assisted workflows into the team: spec-first planning, small reviewed diffs, CI-equivalent validation gates, and runtime checks before merging.
• Owned reliability and debugging in production with Datadog, Sentry and Grafana, including distributed tracing, transactions and event tracking, plus product analytics in Firebase and Metabase.
• Architected the performance strategy for the migration to the Yoga Lotus Design System: 17.83% lower render time and 9.61% lower CPU usage, through a reusable testing pipeline with Flashlight, Maestro and Reassure.
• Automated the component library release with Semantic Release and GitHub Actions, turning a 20-minute manual process into a few clicks. I unblocked design-system adoption for 5+ squads and mentored mid-level engineers.

Biotechnology company that produces sustainable ingredients using synthetic biology. I led the 4UbyTia team to build from scratch the website reaching more than 90k visitors per month. We used the Shopify platform with React, HTML and JS to develop the site that is responsive and optimized to meet SEO and ADA criteria (such as “page speed”, “keyword ranking”, “contrast ratio”, “alt text”, etc.), increasing the visibility and accessibility of customers. Achieved an excellent score on Lighthouse for the web page, indicating optimal performance with 88 points in accessibility, 92 in best practices, 92 in SEO compliance and Time to First Byte (TTFB) with 0.27s. These results show that the web page is fast, secure, easy to use and friendly to search engines.