We are Billie, the leading provider of Buy Now, Pay Later (BNPL) payment methods for businesses, offering B2B companies innovative digital payment services and modern checkout solutions. We are to create a new standard for business payments and have made it our mission to simplify the purchasing experience for all businesses making it a tool for growth. Our solutions are based on proprietary, machine-learning-supported risk models, fully digitized processes and a highly scalable tech platform. This makes us a deep-tech company building financial products, not the other way around. We love building simple and elegant solutions and we strive for automation and scalability.

About the role:

Transform the future of payments for 500K+ companies worldwide as a Senior Frontend Developer on our Checkout Team. Your expertise will revolutionize how millions experience transactions, creating seamless, secure, and scalable payment journeys. You'll take ownership of critical technical landscapes including our modular checkout widget, hosted payment page, Demoshop, and checkout SDK, while bridging connections between external payment service providers and internal teams focused on authorization, risk, and onboarding.

In more detail you will:

• Collaborate with Product Managers and UI/UX Designers to craft exceptional user experiences that millions interact with daily

• Pioneer improvements to development processes that enhance developer experience (DX) without sacrificing delivery speed

• Orchestrate seamless end-to-end design and integration across teams and systems

• Lead crucial trade-off discussions that balance performance, scalability, and user experience

• Elevate team capabilities by mentoring and coaching through workshops, pair programming, and code reviews

• Help shape our team's future by attracting, reviewing, and interviewing top talent

Our frontend architecture employs a monorepo approach with applications built using Next.js, React, and TypeScript, powered by shared libraries and a unified design system. Our technology stack includes Context API and xState for state management, Jest, React Testing Library, Cypress, and Storybook for testing and documentation, plus Nx, Jenkins, and GitHub Actions for CI/CD and tooling.

Who we are looking for:

• Someone with 8+ years of software development experience

• Deep expertise in React.js and component-based architecture

• Advanced TypeScript proficiency

• Hands-on experience with xState and the Context API for state management

• Strong commitment to accessibility standards and comprehensive testing (unit, integration, E2E)

Nice to have:

• Experience with Cypress for integration testing

• Skills in performance optimization and scalability

• Background in implementing and maintaining atomic design systems

• Familiarity with data structures, algorithms, and design patterns

• Knowledge of clean code principles, domain-driven design (DDD), and software architecture best practices

What we offer:

• Challenging and impactful work that drives personal and professional growth

• One of the best Virtual Shares Incentive Programs in the market, so that everyone at Billie is invested in our success

• Flexible work hours and trust in your ability to deliver, empowering you to take control of your work-life balance

• A hybrid working approach that allows you to work from home for up to 3 days per week

• Enjoy 30 days vacation per year on top of paid public holidays, sabbatical opportunities, and extra child sickness leave for parents.

• Our “Catch a Ride with Billie” program that enables discounted access to Berlin Public Transport (BVG), Deutschland-Ticket, OR JobRad

• A yearly development budget to broaden your skill set and horizons

• Free German group classes

• An English-speaking, multicultural team with more than 40 nationalities

• Building meaningful connections with your colleagues through company and team events, interest groups, the Billie run club, game nights, and more, powered by our Formula Fun Team!