Senior Fullstack Engineer & Hands-on Architect (Python / FastAPI) (m/f/d)
- Compensation
- Not disclosed
- Location
- Not listed
- Work setup
- Not specified
- Seniority
- Senior
- Employment
- Full time
- Experience
- Not specified
- Category
- Fullstack
- Posted
Skills
Must have
- Several years of production software development
- Strong backend expertise in Python and FastAPI
- Hands-on architect for product-facing services — not architecture on slides
- Hands-on frontend experience to understand UI integration constraints
- Complex business logic in clean, testable, maintainable code
- Strong API design (contracts, validation, versioning, error semantics)
- Data-centric products: domain entities, lifecycle/state handling, traceability across process steps
- Practical experience working with AI coding agents and the judgment to review their output critically
- Microservice collaboration patterns and integration concerns
- Works directly with business stakeholders and turns vague domain input into a buildable increment
Full description
Senior Fullstack Engineer & Hands-on Architect (Python / FastAPI) (m/f/d)
Standort: Köln, HQ
Eintrittsdatum: Immediately
Arbeitszeit: Full-time
Befristung: Permanent
DEUTZ AG has evolved in recent years into a system provider of innovative and sustainable mobility and energy solutions. With around 6,000 employees worldwide and a global network of over 1,250 sales and service locations in more than 180 countries, we are actively shaping the transformation of mobility and energy supply. We continuously advance our technologies with a clear focus on market requirements, technological innovation, and social responsibility.
As a system provider, our portfolio today goes far beyond the traditional combustion engine: we offer high-performance drive systems for off-highway applications, alternative drive solutions as well as decentralized energy and power generation systems - wherever power, reliability, and adaptability are required. A comprehensive range of services completes our product portfolio, from maintenance and repair to spare parts trading, remanufacturing, and digital, data-based services.
We are building a suite of digital products in the circular economy and remanufacturing space — the lifecycle of engines and components, the processes around reconditioning, and the connected service and partner network.
This is a product role, not a ticket role: you work directly with domain experts, shape what gets built and how, own the architecture of the services behind it, and take features from idea to production. Backend is the center of gravity; fullstack experience is required to work with the frontend team and judge end-to-end feasibility.
We work agentic: AI coding agents are part of the daily toolchain. We expect you to use them to move fast and to review and steer their output with the same rigor you would apply to any production code.
Language: German is the primary project language, English fluent (business-level).Responsibilities:
- Own the technical architecture: domain boundaries, data models, service cuts, integration patterns, ADRs
- Design and implement backend-heavy features and APIs in FastAPI — lifecycle and process data, matching and marketplace-style flows, partner and logistics integration
- Shape the product with domain experts: challenge requirements, propose simpler solutions, define MVP scope and what comes after
- Design resilient, well-documented interfaces to surrounding systems and external partners
- Raise delivery speed through modular architecture, reusable components and effective use of coding agents