(Staff) Software Engineer – Rental Platform (m/f/d)

YOUR ROLE AT SIXT

• You set the architectural direction for the software that runs every SIXT branch. Counter, checkout, key handover, vehicle exchange and return, plus the devices and IT services connecting them. End-to-end across the branch surface
• You design at the software hardware intersection. Counter PCs, customer tablets, POS terminals, scanners, keyboxes — you model how our software speaks to physical devices in real time, and you shape the integration patterns the whole organisation will adopt
• You drive system-design choices across the branch domain — event-driven flows, API contracts, state ownership, device-to-cloud protocols, the boundaries between modern services and legacy interfaces. This is hands-on architecture, not architecture-by-slide-deck
• You grow the engineering practice around you — across the multiple teams that touch the branch (Checkout, Counter, Rental Platform, Turnaround, Keybox, Tablet/POS) through clean design docs, sharp technical reviews, and hands-on engagement when a problem is gnarly enough to warrant it
• You spend real time at the branches. The strongest architecture is shaped where the system actually runs — with agents, with devices, and with customers

YOUR SKILLS MATTER

• Expertise You have several years building production software systems at meaningful scale — customer-facing, multi-region — with a track record of taking systems from "they work" to "they are elegant and they scale"
• System design depth You can sketch the architecture of a non-trivial system and defend every choice — from API design and data modeling, through event/stream patterns and state ownership, down to the trade-offs in how services talk to each other and to the outside world
• Comfort at the software hardware boundary You have shipped software that talks to physical devices — POS hardware, retail or restaurant systems, embedded clients, real-time stateful client-server protocols (MQTT, WebSockets, gRPC streaming). You know "the device is misbehaving" is part of normal operation, and you design for it
• Tech-stack range You are comfortable with Backend in Go / Java / Python, event streams (Kafka), databases (Postgres / Redis), and cloud (AWS / Kubernetes). Bonus for experience integrating with legacy systems you cannot rewrite — only design around
• Influence and craft You have led architectural change across multiple teams through clarity, evidence and follow-through. You write design docs people actually want to read

WHAT WE OFFER

• Extra benefits Enjoy discounts on SIXT rent, share, ride and SIXT+, attractive vehicle leasing offers, and exclusive deals with partners for travel, tech, fashion and more
• Mobility boost We support you with a monthly mobility allowance of 20 per month for even more freedom
• Future security We contribute to your retirement plan and support you with capital-forming benefits to ensure you are well covered
• Feel-good atmosphere Stay active with our modern SIXT gym, various leisure activities like the gaming area or the SIXT choir, and enjoy our high-quality employee restaurant
• Flexibility Enjoy 30 days of vacation and a hybrid working model with flexible hours
• Giving back Take one day each year to volunteer at a charitable organization dedicated to supporting children