Tech Leader - Recommendation Systems / Personalization

Unicorn Foundations: At Cosmose AI, we’re building smart, innovative technology that’s redefining digital marketing and content distribution. Since launching in 2014, we’ve gone from transforming offline shopping to powering personalized content experiences through AI. Founded by Miron Mironiuk, our journey began with one bold idea - and it has grown into a feature that caters to what people care about most, right from their lock screens.

Exceptional Engineering: Our engineering team is far from average; it's a powerhouse of talent. Comprising former FAANG employees and programming champions, they bring deep expertise and a shared commitment to building world-class products. Our strength lies in engineering solutions that leverage the power of AI, Data, and distributed computing. We thrive in a fast-paced startup environment, where agility, creativity, and quality drive everything we do.

Global Presence, Local Innovation: Cosmose AI is a global company with a presence in 8 countries, transforming content engagement through cutting-edge technology. Our flagship product, KAIKAI Lock Screen, delivers AI-powered, personalized content to users worldwide, unlocking new and exciting opportunities for product placement

 

We’re looking for a Tech Leader to guide an established team focused on building and evolving large-scale recommendation systems that power content discovery for millions of users. In this role, you’ll drive the technical direction of our recommendations platform, leveraging machine learning where it adds the most impact while ensuring ideas translate into robust, production-ready systems. You’ll partner closely with engineers, data scientists, and product teams to continuously improve relevance, personalization, and user experience.

 

TL;DR Why us:

  • Big Scale & Startup Culture: Join a company that combines the scale of a major player with the agility and innovation of a startup
  • Exceptional Team: Collaborate with a team of former employees from tech giants like Google, Facebook, ByteDance, and Microsoft, as well as ACM ICPC programming champions
  • Stock Options: As we grow and succeed together, you'll have the chance to benefit from it
  • Flat Structure: Enjoy a flat organizational structure that promotes collaboration and provides opportunities to learn from seasoned technical leadership
  • Challenging Engineering Problems: Tackle challenging engineering problems in areas of high-performance computing, distributed systems, blockchain, and AI/ML

 

What You’ll Do:

  • Lead the recommendations team - define the mission, guide the roadmap, and support day-to-day execution.
  • Work with the team to design, prototype, and deploy ML models that drive content personalization.
  • Collaborate with product, engineering, and data teams to identify impactful research directions that solve real user problems.
  • Turn research into production-ready solutions, balancing innovation with performance, reliability, and scalability.
  • Mentor and grow engineers, fostering a learning culture within the team.
  • Contribute to hiring and shaping the team, bringing in top talent, and helping them succeed.
  • Stay up-to-date with the latest in ML research and tech, and bring those insights to our systems and strategies.

 

What You’ll Need:

  • Experience in building recommender systems. 
  • Solid foundation in computer science and applied mathematics, including statistics, optimization, and algorithms.
  • A track record of bridging research and production - from academic ideas to real-world systems.
  • Proficiency in Python, and working knowledge of ML libraries
  • Experience in leading engineering and research teams
  • Experience in a fast-paced, startup environment, balancing speed, pragmatism, and quality
  • Clear and effective communication within the team (Polish and English required)

 

What you’ll enjoy:

Cosmose provides employees with a great platform to immerse and learn about the most exciting, innovative, and disruptive technologies in offline behavior solutions, unveiling untapped opportunities and profits in the industry. The company constantly innovates to invent and apply world-class technologies with a rockstar engineering team, including four world championship programming medalists. You’ll be working with a strong leadership team backed by experience from various key strategic areas and many other driven & intelligent people across the company. Cosmose is a place where great culture and goals unite departments and individuals to achieve big milestones together.

 

We’re building something big—and we’re just getting started.

If you’re excited about shaping the future of AI-powered mobile content, we’d love to meet you.

 

👉 Be part of the Cosmose story. Apply now!

 

Read more on:
TechCrunch, Business Insider

 

ID: 102 job_post.published_on: 25/03/2026
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