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Fullstack and React Native developer with over 9 years of experience delivering 15+ production mobile and web applications across fintech, fitness, e-commerce, telecommunications and healthcare. Led cross-functional teams of up to 6 people, defined architecture, built reusable component libraries and migrated large codebases to TypeScript. I enjoy shipping type-safe, maintainable products—from mobile features with React Native/Expo and TanStack Query to backend services with Nest.js and Koa.js—while improving reliability through monitoring, analytics, and strong CI/CD practices.…Fullstack and React Native developer with over 9 years of experience delivering 15+ production mobile and web applications across fintech, fitness, e-commerce, telecommunications and healthcare. Led cross-functional teams of up to 6 people, defined architecture, built reusable component libraries and migrated large codebases to TypeScript. I enjoy shipping type-safe, maintainable products—from mobile features with React Native/Expo and TanStack Query to backend services with Nest.js and Koa.js—while improving reliability through monitoring, analytics, and strong CI/CD practices.

Stefan Chelaru

Full Stack Developer, Web Developer, Back-End Developer, +2

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Fullstack and React Native developer with over 9 years of experience delivering 15+ production mobile and web applications across fintech, fitness, e-commerce, telecommunications and healthcare. Led cross-functional teams of up to 6 people, defined architecture, built reusable component libraries and migrated large codebases to TypeScript. I enjoy shipping type-safe, maintainable products—from mobile features with React Native/Expo and TanStack Query to backend services with Nest.js and Koa.js—while improving reliability through monitoring, analytics, and strong CI/CD practices.…Fullstack and React Native developer with over 9 years of experience delivering 15+ production mobile and web applications across fintech, fitness, e-commerce, telecommunications and healthcare. Led cross-functional teams of up to 6 people, defined architecture, built reusable component libraries and migrated large codebases to TypeScript. I enjoy shipping type-safe, maintainable products—from mobile features with React Native/Expo and TanStack Query to backend services with Nest.js and Koa.js—while improving reliability through monitoring, analytics, and strong CI/CD practices.

Available to hire

Fullstack and React Native developer with over 9 years of experience delivering 15+ production mobile and web applications across fintech, fitness, e-commerce, telecommunications and healthcare. Led cross-functional teams of up to 6 people, defined architecture, built reusable component libraries and migrated large codebases to TypeScript.

I enjoy shipping type-safe, maintainable products—from mobile features with React Native/Expo and TanStack Query to backend services with Nest.js and Koa.js—while improving reliability through monitoring, analytics, and strong CI/CD practices.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

Romanian, Moldavian, Moldovan

Fluent

English

Advanced

Work Experience

Fullstack Developer at NTT Data

February 17, 2025 - Present

Delivered and shipped new features for a large-scale pensions React Native app serving thousands of customers. Built type-safe, reusable components with React Native, Expo, and TanStack Query. Instrumented monitoring and analytics using Datadog, Firebase, and Adobe Analytics to improve reliability and visibility into product behavior.

React Native Developer at Ddroidd

October 1, 2024 - December 21, 2024

Developed a React Native app integrated with dedicated dental-monitoring hardware. Implemented reliable Bluetooth and Wi‑Fi pairing flows for real-time device communication and data exchange.

Frontend Developer at Tremend (Publicis Sapient)

July 1, 2024 - September 30, 2024

Built an AI assistant web application enabling energy-industry workers to query technical machine documentation. Implemented secure enterprise access with Microsoft SSO and Azure services.

Lead React Native Developer at 3Pillar Global

August 1, 2022 - July 1, 2024

Led a team of 4 developers and 2 QA engineers across two fitness mobile applications. Created a shared component library and migrated the codebase from Flow to TypeScript. Optimized performance and launched in-app subscription purchases on the app stores.

Lead React Native Developer at Tremend (Publicis Sapient)

March 17, 2021 - July 31, 2022

Directed development of two consumer mobile applications from architecture to release. Established CI/CD pipelines with Fastlane and Jenkins to streamline delivery and reduce release friction.

Fullstack Developer at Safeguard Global

May 4, 2020 - March 16, 2021

Built a payroll web application with React, TypeScript, and a Koa.js backend. Designed RESTful services backed by PostgreSQL and integrated front-end state management and API interactions.

React Native Developer (Senior) at Settle

April 4, 2020 - January 31, 2024

Refactored an entire fintech React Native app onto a new TypeScript architecture and reusable component library. Increased automated test coverage and improved overall application reliability.

React Native Developer at Cult Of Coders

June 30, 2018 - March 31, 2020

Led development of the Collecteurs app, selecting the technology stack and defining milestones. Delivered responsive, reusable UI for iOS and Android and implemented features using Redux, GraphQL, Firebase, and native release automation.

React Native Developer at GreenSoft SRL

October 31, 2017 - June 30, 2018

Developed responsive cross-platform Android and iOS applications. Streamlined release automation with CodePush and supporting CI/CD tooling.

Android Developer at Inovatie Alia

June 30, 2017 - October 31, 2017

Built a social networking Android app using an MVP architecture with Dagger and Retrofit.

Android Developer at Pentalog

September 30, 2016 - June 30, 2017

Developed a movie/TV information app powered by The Movie Database API using Android SDK with Retrofit and local persistence.