Senior Software Engineer

Permanent / Full-time / On site in Ilmenau, Erfurt or Leipzig (3 days per week) / Start ASAP As a Senior Software Engineer in our Meter Data Management (MDM) team, you will combine hands-on software development with technical ownership for a performance-critical product. MDM covers the collection, validation, processing, and management of energy meter data. Our software processes large data volumes and supports critical customer and operational processes within the ZONOS ecosystem. You will provide technical direction within the team, guide solution design, coordinate technical dependencies, and help establish high standards for performance, quality, security, and reliable delivery. This is a technical leadership role without disciplinary people-management responsibility. You will also contribute to migrations between customer systems, ensuring reliable data transfer, validation, integration, and system transition. - Provide technical direction and guide decisions from requirements through reliable delivery. - Own solution design, APIs, integrations, data flows, non-functional requirements, and technical risks within the team’s scope. - Develop and improve scalable software for high-volume, performance-critical data processing. - Guide migrations between customer systems, including data transfer, validation, reconciliation, and cutover activities. - Coordinate technical dependencies between Product, Platform, Operations, QA, DevOps, Security, and Architecture. - Facilitate design discussions, code reviews, technical workshops, and Architecture Decision Records. - Define and promote standards for performance, data quality, testing, maintainability, and operational reliability. - Support profiling, benchmarking, load testing, monitoring, and performance optimisation. - Contribute to backlog refinement, technical estimation, feasibility assessments, and release readiness. - Support CI/CD, observability, secure development, and ISO 27001 requirements. - Coach and support engineers through knowledge sharing, onboarding, mentoring, and constructive technical feedback. - Evaluate suitable agentic AI and AI-assisted engineering solutions while maintaining security and quality standards. - University degree in Computer Science, Software Engineering, Information Technology or a comparable discipline. - Several years of hands-on software development experience with technical ownership in a product or complex software environment. - Strong knowledge of software design, APIs, integrations, data processing, and distributed systems. - Experience with scalable or performance-critical software and large-volume data processing. - Experience with migrations between customer systems or complex software environments. - Ability to structure incomplete requirements, evaluate trade-offs, and guide technical decisions. - Experience with technical design, code reviews, testing, performance optimisation, and reliable delivery. - Strong communication skills and the ability to align different technical contributors. - Professional English; German is an advantage. - Additional relevant degree or vocational qualification is welcome; equivalent practical experience is equally valued. - Experience with Java or Kotlin. - Experience with Kafka, Kubernetes, OpenShift, Oracle, PostgreSQL, REST APIs, or webhooks. - Experience in smart metering, energy, utilities, MDM, or Head-End Systems. - Experience with data migration tools, reconciliation processes, or Architecture Decision Records. - Experience with agentic AI or AI-assisted software development. You will shape the technical direction of a product where performance, data quality, and reliability genuinely matter. You will influence architecture and delivery, support complex customer migrations, and help engineers grow through technical guidance and collaboration. The role offers technical leadership and visible ownership without disciplinary management responsibility. We at Cuculus believe that work should be meaningful, fun, and enable growth. When you join us, you can expect an environment that trusts you, values collaboration, and gives you the freedom to take ownership. - Hybrid working: With regular office presence (3 days per week in Ilmenau, Erfurt or Leipzig). - Flexibility: Flexible working hours & workation option (up to 4 weeks per year). - Mobility: 50% subsidy for the Germany ticket and bike leasing. - Security: Company pension scheme and capital-forming benefits. - Culture: Short decision-making paths, open feedback culture and genuine trust. - Onboarding: A structured onboarding plan and a buddy to support you from day one. - Office Life: We enjoy spending time together in our offices - whether for a coffee, a shared lunch or a spontaneous after-work get-together. - Impact: Meaningful work - software that shapes the energy market of tomorrow.