Full Stack (React Native + Typesсript) for b2c fintech startup that well-funded

Madfish; United Kingdom; Remote; GBP 80,000 - 100,000; Full time

Job summary

A fintech company in the United Kingdom is seeking a Senior Full Stack Engineer with at least 10 years of experience, especially in mobile fintech applications. The role involves delivering pixel-perfect financial applications and building secure serverless APIs. Candidates should possess strong skills in React Native, TypeScript, and familiarity with cryptocurrencies. Join a remote-first team and help redefine AI-driven software development.

Qualifications

• 10+ years of engineering experience, with at least 5 years in mobile fintech applications.
• Mastery of React Native + Expo, with a strong portfolio of pixel-perfect UI/UX work.
• Familiarity with stablecoins, blockchain transactions, or payment APIs.

Responsibilities

• Deliver production-ready, pixel-perfect UI in React Native + Expo.
• Build and maintain scalable serverless APIs.
• Integrate stablecoin and blockchain payment flows.

Skills

React Native

TypeScript

Serverless AWS

WebSockets

AI tooling

Tools

Cognito

JWT

Job description

About the Company:

The company is building a white-label neobank powered by stablecoins, combining the reliability of modern fintech with the intelligence of AI agents. The app offers all the core features of a digital bank - wallets, payments, transaction histories, and dashboards - and integrates Zaira, an AI agent, as a built-in experience for smarter financial interactions.

Technology Stack:

Frontend: React Native + Expo, Tamagui design system, Zustand + TanStack Query, GraphQL/REST, SSE/WebSockets.Backend: Serverless AWS (Lambda, API Gateway, DynamoDB, Kinesis, EventBridge, Cognito, S3/CloudFront).Tooling & Observability: EAS OTA updates, Maestro/Detox E2E tests, Sentry, Better Stack, RudderStack → Amplitude.

What truly sets the company apart is its AI-driven development culture. The team leverages tools like Claude, Cursor, and MCP servers connected to Figma to accelerate and augment workflows. AI is not an add-on - it’s a fundamental part of how the company designs, builds, and ships products.

The Role:

The company is looking for a Senior Full Stack Engineer capable of delivering pixel-perfect financial applications while thriving in an environment where AI is a daily co-pilot. You’ll craft flawless UI in React Native, build secure serverless APIs, and embrace AI tooling to work faster and smarter.

This is an opportunity to work at the intersection of fintech and AI, pushing the boundaries of how AI tools transform software engineering.

What You’ll Do:

• Deliver production-ready, pixel-perfect UI in React Native + Expo, using Tamagui + Style Dictionary for consistent design.
• Own core neobank features, including wallets, payments, transaction histories, onboarding, and notifications.
• Build and maintain scalable serverless APIs (Lambda, API Gateway, DynamoDB, Kinesis, EventBridge).
• Integrate stablecoin and blockchain payment flows with a strong focus on security and compliance.
• Implement real-time features using WebSockets and SSE, including AI-driven chat and streaming UX.
• Optimize for performance (Hermes, Reanimated, FlashList) and observability (Sentry, Better Stack).
• Collaborate closely with design teams using Figma → tokens → Tamagui workflows.
• Leverage AI-driven development tools (Claude, Cursor, MCP integrations) for accelerated coding, testing, and prototyping.
• Contribute to the culture of AI-assisted engineering by experimenting with and integrating new tools to increase productivity.
• Mentor teammates and define engineering standards for AI + fintech best practices.

What We’re Looking For:

• 10+ years of engineering experience, with at least 5 years in mobile fintech applications.
• Proven ability to deliver complex, secure, and visually refined financial apps.
• Mastery of React Native + Expo, with a strong portfolio of pixel-perfect UI/UX work.
• Full-stack proficiency in TypeScript, including serverless AWS backends.
• Experience with secure authentication (Cognito, JWT, device secrets) and financial-grade data handling.
• Familiarity with stablecoins, blockchain transactions, or payment APIs.
• Strong understanding of real-time networking (WebSockets, SSE).
• Comfort working with AI tooling in day-to-day development - ideally using tools such as Claude, Cursor, or AI-assisted IDEs.
• A proactive mindset and excitement to push the frontier of AI-driven software engineering.

Why Join the Company:

• Build a next-generation whitelabel neobank with AI at its core.
• Work across a modern, unified TypeScript stack covering both frontend and backend.
• Shape the future of AI-driven engineering - not just using AI, but defining how it’s done.
• Solve challenging problems in fintech UX, payments, real-time systems, and blockchain.
• Join a remote-first, senior team that values ownership, precision, and innovation.
• Ready to Apply?
• If you’re passionate about building intelligent, design-driven fintech products and want to work alongside AI as your co-engineer, this is the place to do it.
• Join a team that’s redefining how financial technology is created - faster, smarter, and more human-centered than ever before.
• Apply now and become part of a new era of AI-powered software development.