(Senior) Full Stack Engineer (m/f/x) - Based in Germany

Cara Care, a digital health company backed by Bayer AG, is on a mission to improve people’s digestive health through technology. As we expand our product portfolio and modernize our platform, we’re looking for a versatile, pragmatic, and forward-thinking (Senior) Full-Stack Engineer (m/f/x) to help shape the future of digital therapeutics. Your Role You’ll join a cross-functional product team with high ownership, lean processes, and a clear focus: deliver real impact to patients. We’re looking for someone who thrives on solving real-world problems with code, is technology-open, and knows when to build fast and when to build right. Your main focus will be building and improving our backend services, while also contributing to our React Native apps. You’ll also help us use AI tools and coding agents thoughtfully in day-to-day engineering, turning emerging capabilities into reliable workflows that improve how we design, build, test, and operate patient-facing products. Your Responsibilities • Design, build, and operate reliable backend services and APIs , primarily using Python, Django, and PostgreSQL, and contribute targeted changes to our React Native applications with TypeScript. • Use AI coding agents to implement features, refactor code, and generate tests. Define clear tasks and constraints, provide relevant context, Provide clear context and constraints, and validate changes through code review, automated tests, and application-level checks. • Take an end-to-end view of features : understand how mobile clients, APIs, data models, and infrastructure interact, and make pragmatic technical decisions across these boundaries. • Own backend delivery from architecture and implementation to automated testing, deployment, monitoring, and iteration, and continuously improve our CI/CD pipelines. • Improve the performance and reliability of our backend services, APIs, and databases. • Connect AI-assisted development to engineering and design tools via MCP, for example to automate repetitive coding tasks or check frontend changes against Figma designs. Keep patient data, credentials, and other sensitive information out of unapproved tools and workflows. • Collaborate closely with Product, Design, and Medical to explore, define, and deliver patient-centric features across our platform, supporting regulated digital health products for IBS, GERD, and upcoming indications. • Uphold technical excellence in architecture, code quality, and security , including applicable requirements under IEC 62304, BSI TR-03161, and the MDR. • Mentor other developers and help raise the technical bar across the team. Requirements Your Profile Must haves • 5+ years of professional software engineering experience , with a strong backend focus and an understanding of how complete applications work from user interface to infrastructure. • Strong backend development skills in an established language such as Python, TypeScript, Java, or PHP. Our current stack includes Python, Django, and PostgreSQL. • Working knowledge of React Native and TypeScript , with the ability to implement and test changes in an existing mobile application. • Solid understanding of relational databases, API design, distributed systems and services . • Experience writing and maintaining automated tests for backend services and APIs , including unit and integration tests. • Solid understanding of backend security and privacy , including authentication, authorization, secrets management, and secure handling of personal and patient data. • Strong practical knowledge of containers, Kubernetes, and cloud-native architecture , with experience using GCP or another major cloud provider such as AWS or Azure. • Hands-on experience using AI coding agents to implement features, refactor c