(Junior/Senior) Backend Developer (Java / Python, Microservices) – Fixed-Term Contract

Your mission:
Your mission is to develop and maintain a scalable, asynchronous backend that powers OKAPI:Orbits’ end-to-end solutions across mission design, Space Situational Awareness (SSA), Space Traffic Management (STM), Flight Dynamics (FD) and Space Traffic Coordination (STC) — supporting the full lifecycle of satellite operators within an initially fixed-term contract until the end of 2026, with a high likelihood of a subsequent extension of up to two additional years, and a planned start date of April 1, 2026.

You design and implement robust Java-based microservices that process and distribute large volumes of orbital and telemetry data, enabling reliable APIs and automation pipelines.
You work on the systems that allow satellite operators and space agencies to analyse, coordinate, and protect their missions in an increasingly congested space environment.

Research shows that women are less likely than men to apply for a position unless they meet 100% of the listed requirements. Please know that if it’s your case — but you are passionate about space technology, building reliable software, and contributing to a more sustainable space environment — we strongly encourage you to apply.
OKAPI:Orbits already brings together a highly diverse team, and we actively continue to strengthen this diversity, as research consistently shows that heterogeneous teams achieve higher performance and drive innovation.

Your tasks and responsibilities:
• Design, develop, and maintain asynchronous, microservice-based backend systems in Java, with selected components or utilities in Python
• Implement and optimize data processing and distribution pipelines handling large volumes of orbital, telemetry, and mission data
• Design and maintain message-based communication between microservices (e.g. via RabbitMQ or similar brokers)
• Collaborate closely with space engineers and scientists to translate mission requirements into reliable, scalable software solutions
• Take ownership of backend architecture, ensuring performance, fault tolerance, and maintainability across distributed services
• Define and document implementation plans, from system design to deployment in a cloud-native environment
• Maintain a high level of code quality, automated testing, and compliance with security and engineering standards
• Improve CI/CD pipelines, observability, and automation to support continuous delivery and system stability
• Analyze and resolve complex issues in distributed systems, focusing on efficiency and robustness
• Work in small, interdisciplinary teams, contributing backend expertise to cross-functional projects

Your profile:
Must-haves• Degree in Computer Science, Software Engineering, or a related field, or formal IT specialist training
• Several years of professional experience in backend software development with Java (Spring Boot or similar)
• Good working knowledge of Python for scripting, automation, or data processing tasks
• Solid understanding of microservice architectures, asynchronous systems, and distributed communication patterns
• Experience designing and maintaining RESTful and/or message-based APIs (e.g., RabbitMQ)
• Strong grasp of software architecture principles, including modular design, scalability, and maintainability
• Hands-on experience with testing, code quality assurance, and secure software development practices
• Familiarity with Git-based workflows, CI/CD pipelines, and modern DevOps practices
• Knowledge of observability tools (DataDog, Sentry, OpenTelemetry, or similar)
• Experience with database technologies (MongoDB, PostgreSQL, or similar)
• Experience with automated testing frameworks and performance benchmarking
• Ability to plan, implement, and review complex features in collaboration with engineers and scientists
• Background or interest in the space or aerospace domain
• Proactive communication, structured working style, and good English, written and spoken

Nice-to-haves• Experience with containerization and orchestration (Docker, Kubernetes)
• Understanding of security concepts, encryption, and authentication (OAuth2, OpenID Connect)
• Familiarity with agile methodologies (Scrum or Kanban) and collaboration tools (Jira, Confluence)
• Experience in technical leadership, code reviews, and maintaining coding standards

Why us?:
• Flat hierarchy, small teams, flexible hours
• Onboarding in Braunschweig, afterwards on-site in Brunswick, or hybrid in Brunswick or Munich 
• Early ownership, influence technical direction
• Training budget for continuous development
• Corporate benefits like BahnCard 25/50, bike leasing, German classes via Lingoda
• Join space events and conferences, advocate for sustainable space
• Free office drinks, monthly company lunch, regular after-work activities