Senior ML Research Scientist – AI & Generative Recommendation (m/f/d)

Location: Worldwide applications welcome; relocation support to Hamburg, Germany is available for candidates ready to join the team.

Company

hirify.global develops mobile app growth and monetization technologies through its Playtime Arcade and hirify.global Ads products.

What you will do

• Build foundational ML representations and advanced AI capabilities for rewarded engagement and programmatic in-app advertising.
• Translate state-of-the-art research into production-ready systems for high-throughput, real-time recommendation environments.
• Architect multi-stage recommendation pipelines covering generative retrieval, deep ranking, and re-ranking.
• Develop user and ad embeddings, content understanding systems, and sequential recommendation models.
• Optimize and deploy large generative models for sub-millisecond latency and high concurrency.
• Lead architectural discussions, mentor junior scientists, and help define the team’s research direction.

Requirements

• PhD in Computer Science, Statistics, Mathematics, or Physics, or an MSc with extensive industry research experience.
• At least 4 years of experience building large-scale recommender systems in high-throughput environments such as adtech, e-commerce, or social platforms.
• Publications in top-tier venues such as SIGIR, KDD, NeurIPS, or ICLR.
• Strong hands-on expertise with PyTorch and large-scale model optimization, including quantization and distillation.
• Experience developing embeddings and generative or unsupervised models for content understanding and recommendation.
• Ability to convert research prototypes into robust production code for millions of requests and hundreds of millions of users.

Nice to have

• Experience with Ray, Hugging Face, Trino, Athena, or dedicated GPU infrastructure.

Culture & Benefits

• Own projects affecting behavioral data and decisions across more than 770 million users.
• Work on high-impact machine intelligence systems at the intersection of research and production engineering.
• Collaborate with a diverse team representing more than 40 countries.
• Work in a direct, fast-moving environment with frequent solution delivery and cross-team collaboration.
• Relocation support to Hamburg, Germany is available.