About tonies: tonies® is the world’s largest interactive audio platform for children with around 9.3 million Tonieboxes and 119 million Tonies sold. The intuitive and award-winning audio system has changed the way young children play and learn independently with its child-safe, wireless, and screen-free approach. Founded in 2013 by two fathers in Germany, where every second child now owns a Toniebox, the company is replicating its successful business model and expanding internationally. tonies brings the joy and magic of interactive audio entertainment and audio education to children around the world, with products available in over 28 countries on 4 continents and more to come. Tonieboxes have already been activated in over 100 countries. tonies offers a range of more than 1,300 Tonies figurines to be placed on top of the Toniebox and around 4,400 digital titles through mytonies (library and app) – ranging from tonies Originals productions to content from around 400 licensing partners worldwide, including Disney, Warner Bros., NBC Universal, Mattel, Marvel, Paramount, Hasbro, Universal, Sony Music and many more. With an average playtime of ~270 minutes per week it is the perfect everyday companion for little ones. tonies has more than 560 employees, achieved a group revenue of €481 million in the last fiscal year 2024 (33% YoY) and is listed on the Frankfurt Stock Exchange (tonies SE). Joining our tonies team means being part of an inspiring mission to create innovative and meaningful experiences for children around the world. Together, we’re shaping the future of play, learning, and imagination. You as part of tonies: As part of our internal Engineering team, you’ll work closely with an external development partner to advance our firmware. In this role, you’ll be responsible for ensuring the stability and user-friendliness of more than nine million Tonieboxes worldwide — helping to bring joy and sparkles to children’s eyes across the globe. Your tasks and responsibilities will include: Translating electronic requirements into software requirements in the form of user stories Designing both static and dynamic software architectures for embedded software Developing and continuously improving both existing and new software modules Participating in code reviews and performing unit, module, and integration tests Identifying issues during live operation and translating them into actionable development requirements What we are looking for: A degree in Computer Engineering, Electrical Engineering, or a comparable field At least 5 years of professional experience in embedded software development within an IoT environment — ideally with experience using Zephyr Strong familiarity with Jira and Git; SDKs, TDD, and APIs are part of your daily toolkit Confident working directly on hardware, whether using a multimeter, oscilloscope, or logic analyzer Enjoy working in an agile environment and collaborating across teams Fluency in English; German skills are a plus Willingness to meet your team on-site in Düsseldorf approximately once a week Why tonies? Global Teamwork: We collaborate across departmental and country borders on our vision to bring the Toniebox into every child's room in the world. Come as you are: This applies not only to the dress code but also to everything else. Because only where you truly feel comfortable can you give your best. Mobility: Choose the option that suits you best - a Deutschlandticket (public transport ticket) for unlimited mobility, a monthly contribution for an office parking space, a leasing bicycle, or a remote work subsidy. Enhanced Security: Benefit from subsidies for company pension plans, occupational pension schemes, and occupational disability insurance. Rest & Time Off: Enjoy 30 days of paid annual leave as well as three additional days off such as Rosenmontag, Christmas Eve, and New Year's Eve. After one year of employment, you can also use up to 10 "toniecation days" (unpaid leave days). Continuous Learning: Benefit from our internal and external training opportunities as well as an individual learning budget to continuously expand your knowledge. Language Learning & Relaxation: Improve your communication skills with the language learning app Babbel and find relaxation through our access to the meditation app Calm. Discounts: Benefit from attractive discounts on our entire range of tonies products. Good to know: As part of our principles, we are committed to supporting inclusion and diversity at tonies. We actively celebrate our colleagues’ different abilities, ethnicities, faith and gender. Everyone is welcome and supported in their development at all stages in their journey with us. We look forward to hearing from you! Sabine Schykowski Recruiting & Onboarding Partner