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Matheus Guimarães

@matheusguimares

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Senior Frontend Engineer building high-performance React/Next.js data-intensive web products.

Brazil

Message

What I'm looking for

I’m looking for a frontend role where performance is a priority—React/Next.js, data-intensive products, and modern micro-frontends. I want to ship measurable Core Web Vitals wins, collaborate remotely, and own architecture with strong engineering standards.

I’m a Senior Frontend Engineer with 5+ years building high-performance, data-intensive web products on React, TypeScript, and Next.js. I focus on web performance engineering and ship measurable improvements that make user experience faster and more reliable.

In my most recent role, I delivered a documented 35% reduction in load time through code splitting, lazy loading, and bundle optimization. I treated Core Web Vitals (LCP, INP) as a first-class deliverable for a high-volume social platform with thousands of active users.

I also shipped a production micro-frontend architecture using Module Federation, enabling zero-downtime independent deploys per domain. For complex data flows, I’ve built state management solutions with Zustand and Redux Toolkit, and I’ve reinforced quality with Jest, Cypress, and React Testing Library.

I bring fully remote, international collaboration experience from working with U.S.-based stakeholders. Earlier, I founded and led Acomerce with full technical ownership across architecture, delivery, and mentoring, and I later helped build SaaS platforms across multiple verticals using modern React/Next.js and backend integrations.

Experience

Work history, roles, and key accomplishments

Current

Frontend Developer

Current

SEA Tecnologia

Jan 2025 - Present (1 year 5 months)

Develops enterprise-grade web platforms using React, TypeScript, and RESTful APIs in an Agile (Scrum) environment. Builds reusable, performance-optimized component libraries and integrates them with legacy systems.

React TypeScript RESTful APIs Component Libraries Performance Optimization Agile Scrum HTML CSS

Frontend Engineer

DumbOldSpider LLC

Sep 2021 - Jan 2024 (2 years 4 months)

Delivered a documented 35% reduction in load time for a high-volume social platform using code splitting, lazy loading, and bundle optimization while improving Core Web Vitals (LCP, INP). Architected zero-downtime micro-frontends with Module Federation (independent per-domain deploys) and led Zustand-based state management, testing (Jest/Cypress/React Testing Library), and GitHub Actions CI/CD.

React TypeScript Next.js Module Federation Zustand Jest Cypress GitHub Actions

Founder & Full-Stack Dev

Acomerce

Jan 2020 - Sep 2023 (3 years 8 months)

Founded and led Acomerce with end-to-end ownership across architecture, delivery, and team mentoring. Built an AI-powered conversational automation bot (Python + REST APIs) that reduced grocery customer response time by 60% and developed an e-commerce platform that increased online sales by 45%.

React Angular Python REST APIs Docker Architecture Agile Delivery

Full-Stack Developer

Conauto Group

Jan 2021 - Jul 2023 (2 years 6 months)

Built and maintained data-intensive SaaS platforms across multiple verticals using Next.js, NestJS, Zustand/Redux, and MySQL. Improved application performance by 40% through SQL query optimization and caching, with supporting unit/integration testing (Jest) and a focus on responsive, accessible UI and technical documentation.