Goodword
Staff Mobile & AI Platform Engineer
- My contribution
- Owned product-to-store delivery for a React Native, Expo, and TypeScript app; built C++ Nitro Modules and integrated on-device and retrieval-backed mobile features.
Staff Mobile Engineer · Mobile Architecture & PlatformsRemote · Brazil · US & Europe overlap
João Paulo Costa Marra
Mobile architecture and shared platforms, from modernization through release.
- React Native · Expo · TypeScript
- Mobile architecture · Shared platforms
- Remote from Brazil · US and Europe overlap
I’m a Staff Mobile Engineer focused on mobile architecture, modernization, and shared platforms with React Native, Expo, and TypeScript. Across 16+ years in software engineering, I’ve led a six-engineer migration of a production healthcare app to Expo and EAS, owned shared web and mobile components, and delivered an iOS and Android app from architecture through store releases. I work across JavaScript and native code, including C++ Nitro Modules integrated with Swift and Kotlin, and maintain react-native-nitro-markdown, an open-source library with 300+ GitHub stars. My applied-AI experience supports this mobile work through on-device and retrieval-backed features at the product/API layer. Independent projects include typed agent decision APIs with evaluation checks, tool-call scheduling and recovery, and MCP services in TypeScript, Go, and Rust.
Remote availabilityBased in Joinville, Brazil (UTC−3) · US and European time-zone overlap
Selected products
Live on the store
Open to new roles· Staff Mobile · Mobile Architecture · Mobile Platforms
01 / Selected work
Mobile architecture, native integrations, and shared platforms.
Engineering decisions and technical leadership across shipped mobile products.
- Selected proof6engineers on mobile modernization
- Legacy React Native to Expo
- C++Nitro Modules
- Authentication, secure storage, markdown
- 300+GitHub stars
- react-native-nitro-markdown, open source
- 26frontend developers led
- Healthcare workflow modernization
- Agentdecision APIs and MCP
- Evaluation checks, scheduling, recovery
- 16+years in software engineering
- Mobile and web products
02 / Work
React Native products live on the App Store and Play Store.
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 for a production React Native app, setting architecture, review, and release practices.
Gopuff
Senior Frontend Developer
- My contribution
- Owned shared React Native and React Native Web components, diagnostics, automated testing, CI/CD, and local-first web foundations.
Medify Ltd
Senior Frontend Developer
- My contribution
- Delivered React and TypeScript healthcare interfaces for web and desktop, plus C++-backed content workflows and monorepo quality improvements.
Znipe Esports
Senior Frontend Engineer
- My contribution
- Modernized a legacy jQuery esports-streaming platform with React and TypeScript and built React Native and Next.js experiences.
Triggy
Lead Mobile Engineer
- My contribution
- Led the move of an Expo-based sports-data app to React Native for international client products and introduced early TypeScript adoption and testing.
OLX Group
Senior Frontend Engineer
- My contribution
- Delivered dubizzle.com property workflows with React and IndexedDB and built responsive mobile-web flows on the same React front end.
Case studies & guides
How I approach mobile engineering.
A project account, a look inside a public native module, and a guide for teams making their first mobile hire.
English
Modernizing a healthcare app with Expo
My role at Post Op and the decisions that matter in an Expo migration.
Read articleEnglish
React Native markdown performance with Nitro
Where parsing runs, what native code changes, and how to benchmark it.
Read articleEnglish
Hiring your first React Native engineer
Architecture, delivery, and ownership questions to settle before the first release.
Read article03 / Expertise
Mobile architecture and delivery.
Shared platforms and native integrations, with independent tooling as supporting experience.
Stage01Product surface
Mobile foundations
Cross-platform architecture and delivery for reliable iOS and Android products.
- React Native
- Expo
- TypeScript
- New Architecture
- Fabric
- iOS
- Android
Stage02Native runtime
Native integration
Native modules and on-device AI integration for mobile product workloads.
- C++
- JSI
- Nitro Modules
- Swift
- Kotlin
- Native modules
- On-device AI
- Retrieval-backed features
Stage03Supporting tooling
Independent agent tooling
Independent agent tooling built with typed APIs, evaluation checks, recovery, and MCP services.
- Model API integration
- Typed decision APIs
- Golden-case evaluation
- Tool-call scheduling
- Failure recovery
- MCP services
- TypeScript
- Go
- Rust
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++ parsing through a typed Nitro Modules interface, with configurable React Native rendering, streaming APIs, and a headless AST API.
View repository02 / 02
inline-blame-mini
Lightweight inline git blame tooling.
View repository04 / Experience
16+ years in software engineering across mobile and web.
A concise record of hands-on ownership in lean teams and larger organizations, across architecture, implementation, and release delivery.
Goodword
Staff Mobile & AI Platform Engineer
Owned product-to-store delivery for a React Native, Expo, and TypeScript app on iOS and Android: architecture, APIs, implementation, testing, observability, EAS builds, OTA updates, and store releases.
Scope and technical context
- Built C++ Nitro Modules for authentication, secure storage, and markdown on JSI and the New Architecture, with Swift and Kotlin in the shipped iOS and Android binaries.
- Integrated on-device AI and retrieval-backed (RAG) features at the product/API layer while leading a four-engineer product team, hands-on with Expo Router, Sentry, and Maestro.
- React Native
- Expo
- TypeScript
- New Architecture
- Nitro Modules
- C++
- On-device AI
- EAS
- OTA
- Sentry
Post Op
Staff Mobile Architect
Led a six-engineer team through a legacy React Native to Expo modernization of a production healthcare app on iOS and Android, moving builds and releases to EAS.
Scope and technical context
- Set mobile architecture, code review, testing, and release standards while owning implementation, API integration, and native bridges.
- Shipped personalization, rendering-performance, and mobile UX work, including local-first client data with React Query (TanStack Query) persistence.
- React Native
- Expo
- TypeScript
- EAS
- Mobile architecture
- Native bridges
- API integration
- React Query (TanStack Query)
- Local-first
Gopuff
Senior Frontend Developer
Owned the shared React Native and React Native Web component library in TypeScript for commerce and logistics products.
Scope and technical context
- Worked in a four-engineer library team on reusable interfaces, diagnostics, automated testing with Jest and Cypress, and CI/CD for consistent web and mobile delivery.
- Built React and Next.js foundations with React Query caching and local-first client persistence in IndexedDB.
- React Native
- React Native Web
- React
- Next.js
- TypeScript
- React Query
- Component libraries
- Design systems
- Cypress
- CI/CD
Medify Ltd
Senior Frontend Developer
Delivered React and TypeScript healthcare interfaces for web and desktop within a 12-engineer delivery initiative.
Scope and technical context
- Built a C++-backed content-management workflow so non-technical teams could maintain regulated healthcare content.
- Improved monorepo organization, CI/CD, and automated testing for healthcare product delivery.
- React
- TypeScript
- C++
- Monorepo
- CI/CD
- Healthcare technology
- Software testing
- Automated testing
Znipe Esports
Senior Frontend Engineer
Modernized a legacy jQuery esports-streaming platform with React and TypeScript.
Scope and technical context
- Built React Native mobile and Next.js web experiences, including live-streaming interfaces, for a global esports audience.
- Introduced Jest, Cypress, and test-driven development to protect changes to critical product flows.
- React Native
- Next.js
- React
- TypeScript
- JavaScript
- Jest
- Cypress
- TDD
Triggy
Lead Mobile Engineer
Led the move of an Expo-based sports-data app to a production React Native platform for international client products.
Scope and technical context
- Introduced early TypeScript adoption, unit and end-to-end testing, and a repeatable release process for iOS and Android.
- Coordinated product, engineering, and client stakeholders around mobile releases.
- React Native
- Expo
- JavaScript
- TypeScript
- Unit testing
- E2E testing
- Release process
- Technical leadership
OLX Group
Senior Frontend Engineer
Delivered dubizzle.com property-marketplace workflows with React web interfaces and client-side persistence through IndexedDB.
Scope and technical context
- Built responsive mobile-web flows on the same React front end for a high-traffic MENA classifieds audience.
- Helped modernize the legacy frontend architecture and added automated tests for listing and property flows.
- React
- JavaScript
- IndexedDB
- Node.js
- Responsive web design
- Frontend architecture
- Marketplace platforms
- Test automation
UnitedHealth Group
Lead Software Engineer
Led 26 frontend developers through an early, phased migration of healthcare workflows from jQuery and Bootstrap to React and an internal component system.
Scope and technical context
- Defined migration architecture, reusable component patterns, review standards, and delivery sequencing for incremental adoption.
- React
- JavaScript
- jQuery
- Bootstrap
- Frontend architecture
- Healthcare technology
- Component systems
- Technical leadership
Multiple Companies
Independent Software Consultant - Fullstack Engineering
Delivered client products with PHP, JavaScript and jQuery, Node.js, Laravel, WordPress, Joomla, Magento, REST APIs, SQL, and MongoDB across healthcare, e-commerce, and business operations.
Scope and technical context
- Owned discovery, architecture, implementation, integrations, testing, and releases, building fullstack features from the data change through the UI.
- JavaScript
- jQuery
- Node.js
- PHP
- Laravel
- WordPress
- Magento
- SQL
- MongoDB
- REST APIs
05 / Questions
Remote Staff React Native, answered.
What recruiters and founders ask before the first call.
- Are you open to remote Staff Mobile and Mobile Platform roles?
- Yes. I’m based in Joinville, Brazil, and focused on Staff Mobile Engineer, Staff Software Engineer with a mobile remit, and Mobile Platform Engineer roles.
- Which time zones do you overlap with from Brazil?
- I’m based in Brazil (UTC−3) and coordinate with teams in US and European time zones.
- What does mobile platform ownership cover?
- I can establish React Native and Expo foundations, mobile architecture, API integration, testing, EAS builds, OTA updates, observability, and App Store and Play Store releases, then help a small team maintain the platform.
- What is your core stack?
- React Native, Expo, and TypeScript, with C++ Nitro Modules and native Swift or Kotlin when needed. My applied-AI work includes on-device and retrieval-backed mobile features, plus independent agent APIs, evaluation checks, tool-call recovery, and MCP services.