Senior Mobile Engineer responsible for the end-to-end technical direction of a fintech mobile application built from the ground up. Owned the mobile architecture and made key technical decisions focused on scalability, maintainability, security, and long-term code quality.
Led the day-to-day engineering workflow, including breaking down technical requirements, delegating work to junior developers, conducting code reviews, and establishing development standards and engineering practices across the project. Defined and maintained the project's Git workflow, branching strategy, and versioning structure to support a consistent and controlled development process.
Designed and implemented secure authentication and identity flows using encrypted storage, App Attest, biometrics, and platform-level security capabilities. Developed and maintained REST API integrations in close collaboration with backend engineers, ensuring reliable communication between the mobile application and backend services.
Owned the mobile release lifecycle across iOS and Android, including production builds, App Store and Google Play releases, and over-the-air updates. Investigated and resolved production issues while continuously improving application stability, performance, and maintainability.
Also worked on a POS application integrating a third-party native SDK. Designed and implemented native Kotlin modules and a React Native native bridge to expose the SDK's capabilities to the JavaScript layer, keeping the application architecture centered around React Native while encapsulating device-specific and SDK-level functionality within the native layer.
Mobile Software Engineer on a large-scale social networking platform used by thousands of users, built around communities, a live feed, and rich post interactions. Developed and maintained production features focused on scalable UI, performance, and user engagement.
Built the client side of the core social features: communities, feed posting, embedded content inside posts, real-time likes and dislikes, and comments on each post. Used GraphQL with Apollo Client to query and mutate data and keep the feed, reactions, and comments up to date live.
Worked against a role-based access control (RBAC) backend, shaping the interface and the actions available to each user around their role and permissions.
Migrated an existing React Native application from React Native CLI to Expo, improving maintainability and simplifying the development and deployment workflow. Built gamification and engagement features, reusable and performant UI components, and cross-platform experiences using React Native Web, collaborating with designers, backend engineers, and QA to deliver and maintain production features.
Developed mobile features focused on delivery management, real-time tracking, and location-based functionality. Implemented Google Maps integration, route visualization and delivery workflows, as well as delivery tracking capabilities.
Integrated Firebase Cloud Messaging for push notifications and consumed REST APIs while collaborating with backend developers. Also participated in application publishing, maintenance, and production support.
Developed reusable React Native components and mobile functionality for live video streaming experiences. Focused on building maintainable interfaces, improving application usability, and optimizing mobile application performance.
Worked closely with product and design teams to translate requirements into production-ready mobile features.
Developed applications for web and mobile platforms using React and React Native, building reusable UI components and integrating applications with REST APIs, contributing to production-ready features and application maintenance.
Worked alongside senior developers throughout the development process, contributing to feature implementation, code maintenance, releases, and improvements to existing applications.
Six years of experience with React Native and TypeScript, building and shipping production applications across fintech, social networking, logistics, and live streaming. Experienced in owning features end to end, from architecture and implementation to production releases on the App Store and Google Play.
Mobile
React Native
Expo
Expo Router
React Navigation
TypeScript
Zustand
Redux
Context API
React Query
React Native Web
Native SDK Integration
Native Modules
Kotlin
Biometrics
App Attest
Secure Storage
Deep Linking
Push Notifications
EAS Build
EAS Update
Front-End
TypeScript
JavaScript
React
Next.js
React Native Web
Styled Components
React Query
GraphQL
Three.js
REST APIs
Tooling & Practices
Git
GitHub
Firebase
REST APIs
GraphQL
Postman
Android Studio
Xcode
Apple App Store Connect
Google Play Console
EAS
CI/CD
Figma
About me
JP
João PereiraSenior Mobile Developer.
Over 6 years building and shipping production mobile applications with React Native and TypeScript, working across fintech, social networking, logistics, and live streaming.
I specialize in taking mobile features from architecture to production — designing maintainable solutions, integrating APIs and native SDKs, handling platform-specific requirements, and shipping reliable releases to the App Store and Google Play.
I care about clean architecture, thoughtful technical decisions, performance, security, and a smooth user experience. I also enjoy the engineering side of the work: reviewing code, defining standards, breaking down complex problems, and helping other developers grow.
My experience goes beyond implementation. I contribute to architecture and technical decisions, review code, delegate work, establish engineering standards, and help build codebases that are easier to maintain and scale.
I started in JavaScript and web development in 2018 before moving into React Native and making mobile engineering my focus. Since then, I've worked on applications ranging from financial and identity flows to logistics, social platforms, and native device integrations.
I like solving complex mobile problems, keeping the architecture clean, and shipping software that actually works in production.
Frequently asked questions.
Who is João Pereira?
João Pereira is a Senior Mobile Developer with over 6 years of experience building production React Native and TypeScript apps for fintech, social networking, logistics and live streaming platforms.
What does he specialize in?
Taking mobile features from architecture to production: designing maintainable solutions, integrating APIs and native SDKs, handling platform-specific requirements and shipping reliable releases to the App Store and Google Play.
How many apps has he published?
He has published 10+ apps across fintech, social networking, delivery and live streaming.
Is he available for new work?
Yes. He is open to freelance or contract work and to full-time roles. Reach him through the Contact screen, by email at joaovitorspereira@gmail.com, or with the book_intro tool of the MCP server.
Can an AI agent read this portfolio?
Yes. It exposes llms.txt, a JSON Resume file, WebMCP tools in the browser and a remote MCP server with the tools get_resume, get_projects, check_availability and book_intro.
Statement
2026
Senior Mobile Developer
6+ years building and shipping production applications with React Native and TypeScript, across fintech, social networking, logistics, and live streaming.
Today, my focus goes beyond feature development. I work across mobile architecture, technical decisions, native integrations, security, performance, API integration, and production releases for iOS and Android.
I also take ownership of engineering practices within the team — breaking down technical work, delegating tasks, reviewing code, defining development standards, and helping other developers deliver production-ready features.
2024
Fintech & Native Mobile
Moved into fintech development, working on secure banking applications and complex mobile integrations.
Worked with authentication, biometrics, liveness detection, identity validation, secure storage, App Attest, and third-party native SDKs.
Expanded my experience beyond React Native by developing Kotlin native modules and React Native bridges, allowing native SDKs and device-specific functionality to be exposed to the JavaScript layer.
Also took ownership of the mobile release lifecycle, including production builds, App Store and Google Play releases, and over-the-air updates.
2022
Scaling Mobile Across Different Products
Worked across logistics, live streaming, and social networking applications, solving different types of mobile and product challenges.
Built features involving delivery tracking, Google Maps, route visualization, push notifications, reusable components, live-streaming functionality, gamification, and user engagement.
Later joined a large social platform and helped migrate the application from React Native CLI to Expo, improving the development and deployment workflow while continuing to build and optimize production features.
2020
React → React Native
Started my professional development career working with React and React Native, building production applications and reusable UI components.
Worked with REST APIs, application maintenance, feature development, and production releases, while learning how to work effectively within an established engineering team.
This was where I moved from learning the technology to understanding how software is actually built, maintained, reviewed, and shipped.
2018
Where It Started
Started exploring technology and quickly got hooked on JavaScript and front-end development.
What began with an interest in building things for the web eventually led me to React, React Native, and a career focused on building mobile applications used by real people.
What I've Built Along the Way
Mobile
Production React Native applications for iOS and Android, including fintech, social, logistics, and live-streaming products.
Mobile architecture, reusable components, state management, API integration, performance optimization, code reviews, Git workflows, and development standards.
Production & Delivery
EAS Build, EAS Update, App Store releases, Google Play releases, production debugging, and continuous application improvements.
This is what AI agents read: the same portfolio as plain Markdown, plus machine-readable endpoints.
Over 6 years shipping production mobile apps for fintech, social and logistics platforms. I care about clean architecture, smooth UI and getting things through App Store review without losing my mind.
## FAQ
### Who is João Pereira?
João Pereira is a Senior Mobile Developer with over 6 years of experience building production React Native and TypeScript apps for fintech, social networking, logistics and live streaming platforms.
### What does he specialize in?
Taking mobile features from architecture to production: designing maintainable solutions, integrating APIs and native SDKs, handling platform-specific requirements and shipping reliable releases to the App Store and Google Play.
### How many apps has he published?
He has published 10+ apps across fintech, social networking, delivery and live streaming.
### Is he available for new work?
Yes. He is open to freelance or contract work and to full-time roles. Reach him through the Contact screen, by email at joaovitorspereira@gmail.com, or with the book_intro tool of the MCP server.
### Can an AI agent read this portfolio?
Yes. It exposes llms.txt, a JSON Resume file, WebMCP tools in the browser and a remote MCP server with the tools get_resume, get_projects, check_availability and book_intro.
## Skills
- Mobile: React Native, Expo, Expo Router, React Navigation, TypeScript, Zustand, Redux, Context API, React Query, React Native Web, Native SDK Integration, Native Modules, Kotlin, Biometrics, App Attest, Secure Storage, Deep Linking, Push Notifications, EAS Build, EAS Update
- Front-End: TypeScript, JavaScript, React, Next.js, React Native Web, Styled Components, React Query, GraphQL, Three.js, REST APIs
- Tooling & Practices: Git, GitHub, Firebase, REST APIs, GraphQL, Postman, Android Studio, Xcode, Apple App Store Connect, Google Play Console, EAS, CI/CD, Figma
## Work
### Senior Mobile Developer
Senior Mobile Engineer responsible for the end-to-end technical direction of a fintech mobile application built from the ground up. Owned the mobile architecture and made key technical decisions focused on scalability, maintainability, security, and long-term code quality.
Led the day-to-day engineering workflow, including breaking down technical requirements, delegating work to junior developers, conducting code reviews, and establishing development standards and engineering practices across the project. Defined and maintained the project's Git workflow, branching strategy, and versioning structure to support a consistent and controlled development process.
Designed and implemented secure authentication and identity flows using encrypted storage, App Attest, biometrics, and platform-level security capabilities. Developed and maintained REST API integrations in close collaboration with backend engineers, ensuring reliable communication between the mobile application and backend services.
Owned the mobile release lifecycle across iOS and Android, including production builds, App Store and Google Play releases, and over-the-air updates. Investigated and resolved production issues while continuously improving application stability, performance, and maintainability.
Also worked on a POS application integrating a third-party native SDK. Designed and implemented native Kotlin modules and a React Native native bridge to expose the SDK's capabilities to the JavaScript layer, keeping the application architecture centered around React Native while encapsulating device-specific and SDK-level functionality within the native layer.
Technologies: React Native, Expo, TypeScript, Zustand, React Query, REST APIs, Expo Router, Native SDK Integration, Kotlin, Native Bridge, POS, Architecture, Code Review, Git Branching Strategy, App Attest, Biometrics, EAS Update, Apple App Store, Google Play
### Mobile Software Engineer
Mobile Software Engineer on a large-scale social networking platform used by thousands of users, built around communities, a live feed, and rich post interactions. Developed and maintained production features focused on scalable UI, performance, and user engagement.
Built the client side of the core social features: communities, feed posting, embedded content inside posts, real-time likes and dislikes, and comments on each post. Used GraphQL with Apollo Client to query and mutate data and keep the feed, reactions, and comments up to date live.
Worked against a role-based access control (RBAC) backend, shaping the interface and the actions available to each user around their role and permissions.
Migrated an existing React Native application from React Native CLI to Expo, improving maintainability and simplifying the development and deployment workflow. Built gamification and engagement features, reusable and performant UI components, and cross-platform experiences using React Native Web, collaborating with designers, backend engineers, and QA to deliver and maintain production features.
Technologies: React Native, Expo, React Native Web, TypeScript, GraphQL, Apollo Client, React Query, Styled Components, REST APIs
### Mobile Software Engineer
Developed mobile features focused on delivery management, real-time tracking, and location-based functionality. Implemented Google Maps integration, route visualization and delivery workflows, as well as delivery tracking capabilities.
Integrated Firebase Cloud Messaging for push notifications and consumed REST APIs while collaborating with backend developers. Also participated in application publishing, maintenance, and production support.
Technologies: React Native, Firebase, Firebase Cloud Messaging, Google Maps, Redux, REST APIs
### Mobile Software Engineer
Developed reusable React Native components and mobile functionality for live video streaming experiences. Focused on building maintainable interfaces, improving application usability, and optimizing mobile application performance.
Worked closely with product and design teams to translate requirements into production-ready mobile features.
Technologies: React Native, TypeScript, JavaScript, Reusable Components, Mobile UI, Performance Optimization
### Frontend & Mobile Developer
Developed applications for web and mobile platforms using React and React Native, building reusable UI components and integrating applications with REST APIs, contributing to production-ready features and application maintenance.
Worked alongside senior developers throughout the development process, contributing to feature implementation, code maintenance, releases, and improvements to existing applications.
Technologies: React, React Native, JavaScript, TypeScript, REST APIs, Reusable UI Components, Git
## Contact
- Email: joaovitorspereira@gmail.com
- GitHub: https://github.com/JoaoVitorSPereira
- LinkedIn: https://www.linkedin.com/in/joaovitorspereira/