Doctolib is seeking a Senior Software Engineer - Node.js/TypeScript (x/f/m) for its IT team based in Berlin, Berlin. This senior-level position requires a Bachelor's degree and a minimum of 5+ years of relevant experience. You will join the DIAL team in the Phone Assistant domain to design, build, and scale AI-powered features that connect practitioners and patients over the phone, working on a solution combining LLM reasoning, speech recognition, and real-time backend systems launching in Germany, France, and Italy.
Core Responsibilities
- Build and operate backend services in Node.js/TypeScript with Python exposure, focusing on reliability, scalability, and real-time performance.
- Design, evaluate, and ship LLM-based features end-to-end, including prompt engineering, tool calling, structured outputs, guardrails, and fallback strategies.
- Own AI feature quality by building evaluation datasets and scorers, tracking regressions, and making evidence-based ship decisions.
- Deploy and operate cloud-native services on Kubernetes across AWS, Azure, or GCP, while evolving CI/CD pipelines with GitHub Actions.
- Design data models, drive database migrations, and perform performance tuning for PostgreSQL real-time workloads.
- Maintain a high testing bar across unit, integration, and e2e tests, debug distributed systems in production, and contribute to architecture decisions.
Candidate Requirements
- 5+ years of backend engineering experience building scalable, resilient systems in Node.js/TypeScript with some Python.
- Hands-on production experience building LLM-based features, evaluation frameworks, and handling real-world failure modes.
- Proven experience deploying and operating services on Kubernetes within AWS, Azure, or GCP with solid CI/CD practices.
- Strong testing culture, sharp debugging skills for microservices and distributed systems, and a focus on code quality.
- Fluency in English with a collaborative mindset and drive to own problems end-to-end.
- Bonus skills include experience with speech pipelines, event-driven architectures, message brokers, PostgreSQL, and an interest in telephony or real-time communication.
Benefits & Perks
- A Deutschlandticket fully paid for by Doctolib.
- 28 vacation days, plus 1 additional day for each full calendar year of employment up to a maximum of 30 days.
- Work from abroad for up to 10 days per year via flexibility days.
- Company health insurance with supplementary benefits.
Salary for this role is market competitive.