Senior Web & Mobile Developer

Quick Facts

• Role: Senior Web & Mobile Developer

• Focus: Customer-facing web and mobile experiences plus internal Back Office applications

• Work style: Agile, cross-functional delivery in a highly regulated, high-traffic environment

Description

You will help build and evolve production-grade applications across browser-based web apps and native mobile platforms (iOS and Android). The role requires strong React.js expertise and extensive React Native experience with TypeScript, supporting both customer experiences and Back Office operational workflows.

Responsibilities

• Deliver platform improvements across web, iOS, and Android as part of an agile cross-functional team

• Develop and maintain high-performance web applications in React.js and mobile applications in React Native using TypeScript

• Break down features into requirements, contribute to estimation, refine user stories, and define appropriate test coverage

• Write high-quality frontend/mobile code and perform code reviews

• Collaborate with backend teams on API design and technical challenges across REST, GraphQL, and WebSocket integrations

• Support QA, Product, and Release Management to move items safely to production

• Build and maintain mobile capabilities such as push notifications, background processing/loading, and offline/local content storage

• Participate in CI/CD for web and Apple App Store / Google Play releases

• Use analytics, debugging, and performance tooling to improve end-user experience

• Communicate proactively in English with Engineering Managers, Product Owners, and stakeholders

Requirements

• 5+ years of professional frontend and/or mobile application development with recent production experience across both web and mobile

• Strong React.js expertise and 3+ years of production experience developing React Native applications with TypeScript

• Strong TypeScript and JavaScript knowledge; solid HTML and CSS experience

• Extensive state management experience in large applications using MobX, Redux, or similar tools

• Strong experience integrating REST, GraphQL, and WebSocket APIs

• Experience building secure, performant, user-centric applications at scale

• Strong understanding of the client development lifecycle (structure, platform/device APIs, debugging, performance, security, testing, deployment)

• Strong knowledge of client-server architecture and ability to contribute to architecture decisions

• Strong written and verbal communication skills

• Bachelor’s degree in Computer Science or related field, or equivalent practical experience

Benefits

• B2B contract engagement (Poland) supporting a growing technology function