Goodword
Staff Mobile & AI Platform Engineer
- My contribution
- Architected the React Native and Expo mobile platform, including custom C++ Nitro Modules for high-concurrency AI workloads.
Staff Mobile & AI Platform Engineer
João Paulo Costa Marra
First mobile hire or lean-team owner for reliable React Native products.
I work best as the first mobile hire or hands-on owner on a lean team, turning unclear product needs into reliable iOS and Android releases—from discovery and APIs through React Native implementation, testing, EAS/OTA, observability, and App Store / Play Store delivery. 16+ years shipping mobile and web products, including a 90% engagement lift through legacy-to-Expo modernization and custom C++ Nitro Modules.
Selected products
Live on the store
Available for new roles· Notice period: 30 days
01 / Impact
Outcomes before output.
Production outcomes from modernization, native performance, release engineering, and technical leadership.
- Lead outcome90%more mobile engagement
- Legacy-to-Expo modernization
- ~40%better computation
- C++ Nitro Module hot paths
- 75%less technical debt
- Shared platform foundations
- 30%faster deployments
- EAS, OTA, and observability
- 26engineers led
- Healthcare modernization
- 16+years shipping
- Mobile and web products
02 / Work
Products launched, not just screens.
Each role is paired with the App Store product or live website it helped move forward.
Post Op
Staff Mobile Architect
- My contribution
- Led a six-engineer legacy-to-Expo modernization across the patient and clinician apps, increasing mobile engagement by 90%.
Gopuff
Senior Frontend Developer
- My contribution
- Owned shared web and mobile foundations that reduced technical debt by 75% and helped release cycles move 30% faster.
Medify Ltd
Senior Frontend Developer
- My contribution
- Delivered React and TypeScript work across web and desktop healthcare surfaces in a 12-engineer initiative.
Znipe Esports
Senior Frontend Engineer
- My contribution
- Modernized a legacy jQuery streaming product into a React and TypeScript architecture.
Triggy
Lead Mobile Engineer
- My contribution
- Re-architected a legacy Expo system into a scalable React Native foundation for sports-data applications.
OLX Group
Senior Frontend Engineer
- My contribution
- Delivered web development for the Property module of the dubizzle classifieds platform.
03 / Expertise
Depth across the platform stack.
From product UI to C++ hot paths, with the delivery systems that connect them.
Stage01Product surface
Mobile foundations
Cross-platform architecture designed for teams that need to move quickly without sacrificing native quality.
- React Native
- Expo
- TypeScript
- New Architecture
- Fabric
- iOS
- Android
Stage02Native runtime
Native performance
Measured optimization at the boundary between JavaScript, native platforms, and demanding product workloads.
- C++
- JSI
- Nitro Modules
- Swift
- Kotlin
- Native modules
- On-device AI
Stage03Delivery operation
Delivery systems
Release and observability practices that turn a codebase into a dependable product operation.
- EAS
- OTA
- CI/CD
- Maestro
- Sentry
- App Store
- Play Store
Open source · 02 repositories highlighted
Production problems, solved in the open.
Focused tools for React Native performance and developer workflow — small enough to understand, useful enough to ship.
01 / 02
react-native-nitro-markdown
C++ Nitro Module for markdown parsing off the JS thread — built for LLM and chat UIs.
View repository02 / 02
inline-blame-mini
Lightweight inline git blame tooling.
View repository04 / Experience
16+ years of building and leading.
A concise record of first-mobile-hire and lean-team ownership across architecture, implementation, and release delivery.
Goodword
Staff Mobile & AI Platform Engineer
Architected a high-concurrency AI-enhanced mobile ecosystem using React Native, Expo, and custom C++ Nitro Modules, improving computational efficiency by 40%.
Scope and technical context
- Operated as a staff-level IC in a cross-functional four-engineer team, owning delivery, release quality, and performance-first mobile architecture.
- Built on-device LLM integration with C++ optimizations for native-level performance and low latency.
- Delivered retrieval-backed AI experiences connecting grounded output to production mobile and frontend surfaces.
- React Native
- Expo
- TypeScript
- New Architecture
- Fabric
- JSI
- Nitro Modules
- C++
- On-device AI
- RAG
- Sentry
- Maestro
- EAS
- OTA
Post Op
Staff Mobile Architect
Owned a legacy-to-Expo modernization with a six-engineer team, increasing user engagement by 90%.
Scope and technical context
- Integrated AI and retrieval-backed features using TypeScript, APIs, and custom native bridges.
- Shipped a complete UI redesign and feature expansion with improved rendering and state management.
- React Native
- Expo
- TypeScript
- Mobile architecture
- API integration
- Native bridges
- AI product features
- TDD
- E2E testing
Gopuff
Senior Frontend Developer
Owned a shared web and mobile component foundation that reduced technical debt by 75% and improved UI consistency.
Scope and technical context
- Partnered with a four-engineer frontend team on Next.js and Cypress modernization that cut deployment cycles by 30%.
- Integrated diagnostic tooling to improve application performance and product quality.
- React Native
- React Native Web
- React
- Next.js
- TypeScript
- Component libraries
- Design systems
- Cypress
- CI/CD
Medify Ltd
Senior Frontend Developer
Worked as a senior React and TypeScript engineer across web and desktop healthcare surfaces in a 12-engineer initiative.
Scope and technical context
- Engineered a C++ WYSIWYG content-management system for fast non-technical content editing.
- Established a monorepo and automated CI/CD pipeline for critical healthcare features.
- React
- TypeScript
- C++
- Monorepo
- CI/CD
- Healthcare technology
- TDD
- Automated testing
Znipe Esports
Senior Frontend Engineer
Modernized a legacy jQuery application into a high-performance React and TypeScript architecture.
Scope and technical context
- Built Jest and Cypress strategies with near-complete coverage for a high-traffic esports platform.
- Improved release stability and reduced production bug reports.
- React Native
- Next.js
- React
- TypeScript
- JavaScript
- CSS
- jQuery
- Jest
- Cypress
- TDD
Triggy
Lead Mobile Engineer
Re-architected a legacy Expo system into a scalable React Native platform for sports-data applications.
Scope and technical context
- Led major JavaScript-to-TypeScript migrations, improving robustness and onboarding.
- Reduced production bugs across multiple international clients.
- React Native
- Expo
- TypeScript
- Mobile architecture
- TDD
- E2E testing
- International product delivery
OLX Group
Senior Frontend Engineer
Delivered the Property module of dubizzle.com, one of the largest classifieds platforms in the MENA region.
Scope and technical context
- Helped migrate the module from jQuery to a microservices-ready architecture.
- Achieved complete automated test coverage through rigorous test strategy.
- React Native
- React
- JavaScript
- Node.js
- CSS
- Frontend architecture
- Marketplace platforms
- Test automation
- TDD
UnitedHealth Group
Lead Software Engineer
Led a 26-developer frontend group through migration strategy, architecture, review standards, React adoption, and an internal component system.
Scope and technical context
- Modernized critical healthcare workflows from jQuery and Bootstrap to reusable React interfaces.
- Built the business unit’s first bare React Native app and defined its initial mobile architecture.
- React
- React Native
- JavaScript
- CSS
- jQuery
- Frontend architecture
- Healthcare technology
- Component systems
- Technical leadership
Multiple Companies
Independent Software Consultant · Full-stack Engineering
Delivered full-stack projects for healthcare, e-commerce, and enterprise clients.
Scope and technical context
- Modernized legacy systems into maintainable web and API platforms used by large audiences.
- Progressed from hands-on delivery into architecture ownership and stronger TypeScript, testing, and delivery practices.
- JavaScript
- Node.js
- PHP
- WordPress
- Joomla
- Magento
- Laravel
- SQL
- MongoDB
- REST APIs
- C#
- CSS