Role Description We need a Senior Full-Stack Developer who leans frontend – someone who makes our product look and feel as good as it works under the hood. You'll own features end-to-end, thinking through the entire user flow, edge cases, error states, and architecture before you start building. You work with high autonomy and take real ownership – we trust you to make good decisions and deliver clean solutions. - Drive frontend improvements – not just fixing bugs but proactively elevating UX and visual quality on a regular cadence. - Build and own complex full-stack features in our accounting platform. - Use Claude Code, Cursor, or similar AI engineering tools as your primary development workflow. - Adapt and extend our Python/FastAPI & Django backend where needed (CRUD-level changes and beyond). - Contribute to code quality and architecture decisions in a small senior team. Qualifications - Professional experience in software development with a proven track record of owning and delivering complex projects. - Expertise in React to build high-quality, accessible, and production-ready user interfaces. - A sharp eye for design that ensures layouts and components are implemented with pixel-perfect accuracy. - Hands-on skill with AI-assisted engineering using tools like Cursor, Claude Code, Codex, or GitHub Copilot. - The ability to work across the stack by independently navigating and extending a Python/FastAPI backend. - A systems-thinking mindset to map out full features, edge cases, and failure modes before writing any code. - Fluency in English, while any knowledge of German is a welcome bonus. Requirements - Background in agentic AI systems or LLM-powered products (nice to have). - Familiarity with B2B fintech, PostgreSQL, or German accounting standards like DATEV (nice to have). Benefits - A small team of strong, senior engineers who respect each other's time. - Real autonomy and ownership from day one. - Work that's genuinely hard and interesting – German tax law + AI agents is not a solved problem. - Competitive salary and a product that's actually used by real customers daily. - Almost no meetings – on average 95% focus time per day. - 100% Remote option, option to work abroad and no minimum required office attendance. - Fully flexible working hours apart from Daily Standup. - Berlin location preferred but remote possible.

• Design, develop, test, and deploy scalable software applications using modern engineering practices • Write and maintain comprehensive automated tests, applying approaches such as TDD/BDD and early quality validation • Integrate automated testing, security scanning, dependency checks, and quality gates into CI/CD pipelines to prevent defects and vulnerabilities early • Participate in and lead code reviews, offering constructive feedback on code quality, security, testability, and maintainability • Use cloud platforms and DevOps tools to automate infrastructure and enable reliable, efficient delivery workflows • Collaborate closely with product managers, designers, and fellow engineers to translate business needs into well‑designed technical solutions • Improve application performance, scalability, and reliability in distributed and microservices‑based systems • Mentor junior developers and contribute to a culture of continuous learning and technical excellence • Stay current with emerging technologies, tools, and best practices, and share knowledge with the team

At Kroo Bank, we’re building the future of banking with modern technology and a culture that values innovation, collaboration, and impact. Unlike traditional banks or outsourcing firms, our engineers shape real products used by thousands of customers every day in the UK. Why join us? - Be part of a new generation UK bank. Kroo was awarded a full UK banking licence in 2022, making us one of only a handful of fintechs to achieve this milestone. - We’re one of the fastest-growing banks in the UK, reaching £1 billion in deposits faster than any of our peers, with 200,000+ customer accounts and growing every day. - Work with a modern stack: Clojure, React Native, Kafka, AWS, Docker, Terraform. - Practise or learn functional programming (we’ll support you even if you’re new to it). - Be part of a cross-functional squad where engineers, designers, testers and product managers collaborate as equals. - Permanent employment contract, 100% remote, with flexible hours and a healthy work-life balance. - Competitive salary and stock options, so you share in the success of the company. - Join a young, dynamic, and mission-driven organisation where your work directly shapes how people bank in the UK. What you’ll do - Build and deliver new features end-to-end, from idea to production, in a modern CI/CD environment. - Work across the stack including backend microservices (Clojure, Kafka, AWS, Postgres) to frontend (React Native, React, NextJs). We offer opportunities to specialise or grow as a full-stack engineer. - Collaborate daily with product, design, and engineering colleagues to ship customer-facing features in an agile environment based on Kanban and XP practises such as pair programming and test driven development.   - Write clean, maintainable, and testable code, and participate in code reviews. - Contribute to system design discussions and bring ideas to improve scalability and resilience. - Keep learning, diving deeper into banking products, functional programming, mobile frameworks, or cloud infrastructure. - Optionally, contribute back to open source and share knowledge with the wider engineering community.

• Develop and deploy new products and features to support rapid iteration and continuous improvement. • Collaborate with stakeholders to understand business requirements, operational processes, and technical needs. • Architect, design, and document software applications to ensure solutions meet functional, performance, scalability, and reliability requirements. • Collaborate with analysts, designers, and development teams in the planning and implementation of new software applications and enhancements. • Research emerging application development technologies, frameworks, and standards to support innovation and continuous improvement. • Develop high-quality, high-performing applications that adhere to established coding and architectural standards. • Develop and maintain reusable libraries and components to maximize code reuse and ensure consistency across the application portfolio. • Participate in code reviews, Agile ceremonies, and continuous improvement initiatives to support team development and high-quality software delivery. • Conduct performance testing and debugging activities to identify issues, improve performance, and ensure application stability. • Promote and share knowledge of application development best practices and modern software architecture principles. • Provide technical leadership and guidance to development team members regarding architecture, development standards, and best practices. • Perform other duties as assigned.