Machine Learning Engineer (f/m/d)

adjoe is a leading mobile ad platform developing cutting-edge advertising and monetization solutions that take its app partners’ business to the next level. Part of the applike group ecosystem, adjoe is home to an advanced tech stack, powerful financial backing from Bertelsmann, and a highly motivated workforce to be reckoned with.

Meet Your Team: Programmatic Data Science

Did you know that in-app ads are sold in a real-time auction before they get rendered in thousands of mobile apps? Dozens of ad networks compete for every single view, choosing their best ad and deciding what price to bid in just a couple hundred milliseconds. We at adjoe have developed our own ad network that takes part in this competition, going against giants like Google, Meta and TikTok to present its own ads.

In the competitive real-time bidding landscape, the WAVE Data Science team operates at a rapid pace, developing cutting-edge algorithms, to create systems that outperform industry giants. Our approach is deeply rooted in rigorous research into user behavior, publisher and advertiser objectives, ensuring an optimal user experience. We are a fast-moving team that rapidly translates theory into impactful solutions, using state-of-the-art technologies and collaborating closely with product and business stakeholders.

• Architect and deploy a high-throughput, low-latency recommendation system capable of scaling to millions of users and billions of daily requests.


• Leverage Large Scale Dataset: identify relevant signals to improve model performance.


• Develop and refine relevance models, bidding strategies, using advanced machine learning techniques, directly influencing the company revenue.


• Own the end2end lifecycle of production machine learning models, including rigorous monitoring, in-depth performance analysis, and data-driven iterative improvements.


• Collaborate closely with backend engineering teams to design and implement robust, scalable, and production-ready machine learning solutions, ensuring seamless integration and industrialization of reusable models and assets.


• Conduct rigorous A/B testing and experimentation, Validate your hypothesis and measure the impact of new features on key business metrics.

• You have 2+ years of proven experience developing and deploying production-grade recommendation systems in a high-volume environment (e.g., adtech, e-commerce, search).


• You demonstrated expertise in deep learning, with hands-on experience building and optimizing neural network architectures for recommendation tasks using TensorFlow, PyTorch or Jax.


• You are a software engineer at heart.


• Plus: you have understanding of data engineering principles


• Plus: experience working with large-scale distributed data processing systems (e.g., Spark, Flink, Kafka) and data storage solutions (e.g., AWS Athena, S3, MySQL).

• Work-Life Package: 2 remote days per week, 30 vacation days, 3 weeks per year of remote work, flexible working hours, dog-friendly kick-ass office in the center of the city.


• Relocation Package: Visa & legal support, relocation bonus, reimbursement of German Classes costs and more.


• Happy Belly Package: Monthly company lunch, tons of free snacks and drinks, free breakfast & fresh delicious pastries every Monday


• Physical & Mental Health Package: In-house gym with personal trainer, various classes like Yoga with expert teachers.


• Activity Package: Regular team and company events, hackathons.


• Education Package: Opportunities to boost your professional development with courses and trainings directly connected to your career goals