Senior Python Engineer (Embedded project) (#5821)

We are looking for an experienced Backend Developer / Test Developer with strong Python skills to join the team and contribute to the development of a common web-based project layer for roadside measurement systems.

The goal of the stream is to develop a reusable HMI and API architecture that can serve multiple roadside products and measurement systems, with only minor adaptations and extensions required for different platforms.

The HMI will provide a modern, touch-friendly, web-based user interface with harmonized workflows and a recognizable design across products. The solution will be designed to support different application types and measurement systems while maintaining scalable client performance, including under bandwidth-constrained conditions.

The role has a strong focus on the backend/API layer and automated testing, ensuring reliable data flow from HMI interactions through the API Gateway and service layer to the Shire backend services.

Key Responsibilities:

• Develop and maintain backend modules, utilities, and automated testing solutions using Python.
• Develop and maintain automated API and integration test suites covering application-layer endpoints.
• Test and validate GraphQL and RESTful/gRPC APIs, including schemas, queries, mutations, subscriptions, and service interactions.
• Verify end-to-end data flow from HMI user interactions through the API Gateway / Service Layer to Shire backend services.
• Validate API contracts, data structures, and schema consistency across system components.
• Develop integration, regression, and contract tests to ensure reliable communication between HMI and backend services.
• Integrate automated tests into CI/CD pipelines, working closely with DevOps and development teams.
• Perform root-cause analysis of system failures at the protocol, logging, and container levels, rather than limiting investigations to UI-level issues.
• Work with embedded systems and target hardware in Jenoptik office/lab environments, including via VPN or remote access.
• Investigate communication and integration issues involving ROS middleware, embedded systems, and roadside hardware.
• Work closely with Lead Frontend Developers to ensure reliable integration between the web-based HMI and backend services.
• Collaborate with DevOps to integrate API sanity checks, regression testing, and automated validation into Jenkins / GitLab CI pipelines.
• Support the development of a modular architecture that can be reused across multiple measurement systems with minimal adaptations.
• Contribute to troubleshooting and continuous improvement of the overall HMI/API solution.

Python & Backend Development

• Strong professional experience with Python.
• Experience developing backend modules, utilities, and automation frameworks.
• Good understanding of backend application architecture and service-based systems.

API & Communication Technologies

• Strong experience with GraphQL, including:
• Schemas
• Queries
• Mutations
• Subscriptions
• Experience with RESTful and/or gRPC APIs.
• Understanding of API contracts, data structures, and service-to-service communication.

Automated Testing

• Strong experience with PyTest.
• Experience developing integration and API tests.
• Experience with contract testing and end-to-end testing.
• Experience integrating automated tests into CI/CD pipelines.
• Practical experience with GitLab CI and/or Jenkins.

Embedded & System Environment

• Working knowledge of ROS / Robot Operating System and middleware protocols used for communication with embedded/roadside hardware.
• Good understanding of Linux, including shell scripting and system troubleshooting.
• Experience working with Docker containers, particularly in embedded or constrained environments.
• Ability to troubleshoot issues across multiple system layers, including protocols, logs, containers, APIs, and backend services.

System & Architecture Understanding

• Ability to understand the system holistically from end to end, including:
  HMI Web Interface → API Gateway / Service Layer → Shire Backend Services
• Ability to analyze dependencies and data flows across different application layers.
• Understanding of modular and reusable software architectures.

Nice to Have

• Experience working with roadside systems, traffic management, or measurement systems.
• Experience interacting directly with physical target hardware in laboratory or development environments.
• Experience with ROS2 and related middleware.
• Experience with performance and reliability testing under bandwidth-constrained conditions.
• Experience working with web-based HMI systems or touch-friendly interfaces.
• Familiarity with frontend technologies and modern web application architecture.
• Experience with embedded Linux environments.