Frontend Senior Software Engineer with more than 5 years of professional experience building modern web applications and developer tooling.

I enjoy working on complex UI systems where architecture, performance, accessibility, and long-term maintainability matter just as much as shipping features.

• Designing scalable frontend architectures (Clean / Hexagonal Architecture)
• Building and maintaining component libraries and design systems
• Defining frontend testing strategies (unit, integration, E2E, visual regression)
• Performance optimization and Core Web Vitals
• Accessibility-first development (WCAG 2.1)
• Contract-driven frontend development and API integration
• Collaborating closely with design, product, backend, and QA teams

Frontend

• React, Next.js, TypeScript
• Redux (client state), React Query (server state)
• HTML, CSS, Tailwind

Architecture & Data

• Frontend System Design
• Clean Architecture, Hexagonal Architecture
• REST APIs, GraphQL, API Contracts

Testing & Quality

• Jest, React Testing Library
• Cypress, Playwright
• Cucumber, Gherkin
• Mock Service Worker (MSW)
• Storybook, Chromatic (visual regression)

Performance & Delivery

• Core Web Vitals, Lighthouse
• Docker, CI/CD pipelines

I treat frontend applications as long-lived systems, not just collections of components.

That means:

• Separating domain logic from UI frameworks
• Being intentional about state ownership and data flow
• Choosing testing approaches based on risk, not dogma
• Designing UI systems that scale across teams
• Making tradeoffs explicit and documented

Pinned repositories on my profile highlight:

• WIP

Each repository includes documentation explaining why certain decisions were made, not just how they were implemented.

• Advanced frontend testing strategies
• Contract-driven frontend development
• Scalable design systems and UI infrastructure
• Practical AI integration patterns in frontend applications

• LinkedIn: https://linkedin.com/in/fabio-mar
• GitHub: https://github.com/fabiomarcellusdev