Job description
Lead Fullstack Engineer (f/m/d)
Company Overview
hallo theo
Job Summary
As Lead Fullstack Engineer at hallo theo, you design, build and operate the core systems of our AI-native property management platform. You work hands-on across the stack – from intuitive frontends to robust backend services and data flows – and take real ownership for critical user journeys. You work with great attention to detail, empathy and a solution-oriented mindset, with a strong feel for both our users and our technology, and you help turn ambiguous problems into simple, impactful product experiences.
Key Responsibilities
- Own the end-to-end delivery of features and services – from discovery and technical design through implementation, testing, rollout and monitoring in production.
- Build and evolve reliable backend and frontend components (APIs, services, UIs) that integrate with our web tech stack and data layer.
- Improve our architecture and codebase: refactor, define clear interfaces and keep our platform secure, observable and maintainable.
- Collaborate closely with Product, Design and Operations to shape scope, break down complex problems and make pragmatic trade-offs between speed and quality.
- Act as a technical sparring partner and mentor for other engineers, supporting good engineering practices and a healthy engineering culture.
Requirements / Qualifications
- 6–8 years of experience in software engineering, ideally in product-driven environments (startups, scale-ups or similar), with a strong track record in complex and uncertain projects.
- Strong product mindset: you think in user journeys and outcomes, not just tickets, and you are comfortable making trade-offs under ambiguity.
- Solid understanding of LLMs, RAG and current AI trends, and motivation to apply them pragmatically in a real product.
- Proficient in at least one modern programming language and experienced in a web tech stack (e.g. Python and SQL, plus modern web frameworks and APIs).
- Experience operating services in the cloud (e.g. AWS, GCP or Azure), including CI/CD, logging, monitoring and basic security practices.
- Business-fluent German (C1 or higher) and strong English skills, as you’ll work with German-speaking stakeholders and an international team.
Preferred Qualifications
- Experience in domains with complex operations or workflows (e.g. proptech, fintech, marketplaces or B2B SaaS).
- Prior experience in a “tech lead” capacity (leading projects or streams), even without formal line management.
