sonnen GmbH

Product Manager

• Du verantwortest Hardware-Produkte (z. B. Batteriespeicher & Charger) über den gesamten Produktlebenszyklus – von der Idee bis zum End of Life
• Du analysierst Markt, Wettbewerb und Kundenbedürfnisse im Device-Umfeld und leitest Produktoptimierungen sowie Neuentwicklungen ab
• Du definierst und priorisierst technische Anforderungen (z. B. Lastenhefte) in enger Abstimmung mit der Entwicklung
• Du steuerst die Umsetzung neuer Geräte und Features mit R&D und stellst Qualität, Time-to-Market und Zielerreichung sicher
• Du planst Produktlaunches und überwachst die Performance deiner Produkte anhand relevanter KPIs

Product Manager – Hardware, Stromspeicher

Full-stack Engineer

• Participate in the entire development process, including refinements, code reviews, tests, deployment and monitoring on production.
• Maintain and extend our Ruby on Rails based services.
• Implement user friendly frontends using modern technologies including Hotwire.
• Build and maintain GraphQL interfaces and RESTful endpoints (JSON:API).
• Convert acceptance criteria into test cases written in RSpec framework.
• Write new and update existing documentation entries.
• Contribute to the implementation of micro-services.
• Push and follow up on builds and deploys, using CI/CD pipeline tools.
• Collaborate with a development team on the planning and implementation of tasks, troubleshoot of issues, and refactoring.
• Interpret log messages and mitigate errors coming from our monitoring tools.
• Collaborate closely with cross-functional teams in an Agile development environment, familiar with a Software Delivery Lifecycle following Scrum practices.

Fullstack Engineer

Supply Chain

• You plan and manage international shipments based on SAP data and ensure compliance with applicable hazardous materials regulations.
• You coordinate freight forwarders, optimize global delivery routes, and actively reduce costs and lead times.
• You work closely with suppliers, customers and internal teams to synchronize goods flows and ensure just-in-time deliveries.
• You monitor inventory worldwide and ensure our components are in the right place at the right time.
• You analyze shipping data, derive optimization measures and develop solutions for disruptions across the supply chain.

Global Logistics Coordinator – Supply Chain

Analytics Engineer

• Partner with business stakeholders and subject matter experts to understand analytical needs, identify opportunities, and define requirements for data products and analytical solutions.
• Translate business requirements into scalable data models, curated datasets, and actionable insights that enable data-driven decision-making.
• Design, develop, and maintain data products by integrating data from operational systems, backend services, SAP solutions, and other internal and external data sources.
• Collaborate with software engineering and data engineering teams to ensure reliable integration of data into sonnen's analytics platform and data ecosystem.
• Contribute to the evolution of our data architecture, data governance, and analytics strategy, helping establish sustainable and scalable data products.
• Develop and maintain data transformation logic, analytical datasets, and semantic models that support reporting, analytics, and advanced use cases.
• Implement data quality controls, monitoring mechanisms, and validation processes to ensure data accuracy, consistency, and trustworthiness.
• Drive continuous improvement of our data products and analytics capabilities by identifying gaps, opportunities, and emerging technologies.
• Ensure high standards for documentation, maintainability, and software engineering practices using version control and collaborative development workflows.

Data & Analytics Engineer

Backend Engineer

• Contribute to a distributed Virtual Power Plant controlling tens of thousands of home battery systems across eight countries in real time.
• Design, analyze, and improve algorithms for grid services — FCR, intraday trading, demand response, and spot optimization.
• Develop algorithms that optimize energy use within individual households, balancing self-consumption and cost savings under dynamic energy prices.
• Build and run simulations to model real battery behavior and validate algorithmic decisions.
• Analyze data streams to monitor system health and develop new signals that add value to the VPP.
• Implement protocols, backend services, and client features in a production Elixir/Rust codebase.

Software Engineer, Elixir / Rust

Accountant

• Timely preparation, analysis and quality assurance of monthly and annual financial statements in accordance with German GAAP (HGB)
• Assessment of business transactions and correct accounting under HGB
• Preparation of VAT returns, tax returns and statistical filings
• Execution of intercompany reconciliations at national and international levels
• Working with large data sets, using Excel for analysis and process optimization
• Supporting the head of accounting and actively shaping financial processes

Financial Accountant – Senior Accountant

Customer Success Manager

• You support our installation partners and customers by answering technical inquiries (by phone and email) about our electrical devices, such as battery storage systems.
• You ensure a smooth service process to achieve high customer satisfaction.
• Administrative tasks, such as recording customer data in our database, are part of your responsibilities.
• You analyze error messages and carry out troubleshooting according to established processes and using our tools.
• You meet your performance metrics and keep your targets firmly in focus.

Customer Success Specialist – 2nd Level Support

Support Engineer

• Provide expert technical support to our international partners via phone, chat, and email.
• Handle and document all partner inquiries related to our battery storage systems and chargers using Salesforce.
• Diagnose technical issues remotely, plan on-site service assignments, and coordinate fault clearance and maintenance activities.
• Ensure high partner satisfaction through efficient, cost-effective, and solution-oriented case handling.
• Deliver technical training and guidance to sonnen partners.
• Monitor local regulatory developments to ensure product compliance, and communicate relevant updates or improvement needs to the team lead.
• Meet regularly with our Premium Partners in Belgium and the Netherlands to strengthen cooperation and discuss service-related topics on-site.

Technical Support Specialist, Belgium & Netherlands

SDET

• Reviewing and testing modern analog and digital electronics
• Supporting product development through continuous testing
• Supporting the product compliance team and providing verification reports
• Identifying opportunities to optimize existing product designs and mechanisms