Head of Large-Scale Recommendation Systems

Cosmose, Inc.; Warszawa; On-site; PLN 350,000 - 520,000; Full time

Benefits offered by this job

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Job summary

Cosmose AI is seeking a Tech Leader to guide an established team building large-scale recommendation systems powering content discovery for millions of users. You will set the technical direction, drive ML-driven personalization, and collaborate with engineers, data scientists, and product teams to turn ideas into robust systems.

You will mentor engineers, help with hiring, and stay ahead of ML research to improve relevance, user experience, and scalability.

Qualifications

• Experience building high-scale distributed systems with ML components.
• Strong CS and applied math background including statistics and optimization.
• Bridge research ideas to production systems.
• Proficient in Python and ML libraries.
• Experience leading engineering and research teams.
• Thrives in fast-paced startup environments balancing speed and quality.
• Excellent Polish and English communication within a team.

Responsibilities

• Lead the recommendations team: define mission, roadmap, and day-to-day execution.
• Design, prototype, and deploy ML models for content personalization.
• Collaborate with product, engineering, and data teams on research directions.
• Translate research into production-ready, scalable solutions.
• Mentor engineers and grow the team; contribute to hiring.
• Stay updated on ML research and bring insights to systems and strategy.
• Balance innovation with performance, reliability, and scalability.

Skills

Distributed systems

Python

Leadership

Communication

ML libraries

Research-to-production

Tools

Python

Job description

Cosmose AI is seeking a Tech Leader to guide an established team building large-scale recommendation systems powering content discovery for millions of users. You will set the technical direction, drive ML-driven personalization, and collaborate with engineers, data scientists, and product teams to turn ideas into robust systems.

You will mentor engineers, help with hiring, and stay ahead of ML research to improve relevance, user experience, and scalability.