<div class="show-more-less-html__markup show-more-less-html__markup--clamp-after-5 relative overflow-hidden"> <p><strong>Senior Machine Learning Engineer — AdTech &amp; Recommendation Systems</strong></p><p><br/></p><p><strong>What's On Offer</strong></p><ul><li>Competitive salary, depending on experience and seniority</li><li>Hybrid working model based in Hamburg, Germany, with relocation and visa support available</li><li>International, English-speaking environment</li><li>Genuine technical ownership on large-scale deep learning, recommendation, and real-time serving systems</li><li>Strong opportunities for career growth within a fast-moving Data Science organization</li></ul><p><br/></p><p><strong>The Role</strong></p><p> We are supporting a leading mobile advertising platform, operating at massive scale across hundreds of millions of users, in growing their Machine Learning Engineering team. You'll be working on real-time bidding optimization, ad ranking, and conversion modeling — systems that make live decisions in milliseconds at massive scale.</p><p><br/></p><ul><li>Build and optimize deep learning models for recommendation, ranking, and bidding</li><li>Design and deploy real-time, low-latency inference systems serving live production traffic</li><li>Develop scalable machine learning solutions using modern deep learning techniques</li><li>Work with massive production datasets to improve model performance and business outcomes</li><li>Own models end-to-end — from research and experimentation through production deployment and A/B testing</li><li>Collaborate closely with engineering and product teams to translate ML into measurable business impact</li></ul><p><br/></p><p><strong>What We're Looking For</strong></p><ul><li>5+ years of experience in Data Science, Machine Learning Engineering, or Applied Science</li><li>Strong hands-on experience with deep learning frameworks (PyTorch and/or TensorFlow)</li><li>Experience with large-scale recommendation systems, ranking, or personalization models</li><li>Experience building and deploying real-time, low-latency production ML systems (online inference, live serving) — this is essential</li><li>Strong Python and SQL skills, with experience integrating models into production pipelines</li><li>Experience in AdTech, mobile gaming, e-commerce, or a similarly large-scale consumer platform</li><li>Experience with real-time bidding or programmatic advertising is a strong plus</li></ul><p><br/></p><p>This role is focused on recommendation, ranking, and bidding systems — not conversational AI, RAG, or LLM application engineering. If your recent work has been primarily LLM/GenAI/chatbot development without a strong recommendation systems foundation, this likely isn't the right fit.</p><p><br/></p><p><strong>Apply</strong></p><p>If you're passionate about building large-scale, real-time machine learning systems in a fast-paced, high-impact environment, we'd love to hear from you. Apply today or get in touch for a confidential discussion.</p> </div>