Senior software engineer (LLMs and Agentic Systems)

Nebius

Nebius

Software Engineering
Europe · Remote
Posted on Mar 14, 2025

Why work at Nebius

Nebius is leading a new era in cloud computing to serve the global AI economy. We create the tools and resources our customers need to solve real-world challenges and transform industries, without massive infrastructure costs or the need to build large in-house AI/ML teams. Our employees work at the cutting edge of AI cloud infrastructure alongside some of the most experienced and innovative leaders and engineers in the field.

Where we work

Headquartered in Amsterdam and listed on Nasdaq, Nebius has a global footprint with R&D hubs across Europe, North America, and Israel. The team of over 500 employees includes more than 400 highly skilled engineers with deep expertise across hardware and software engineering, as well as an in-house AI R&D team.

The role

We are Nebius AI R&D team, a research team with a focus on large language models and agentic systems. Some examples of our work in this area include:

  • investigating how test-time guided search can be used to build more powerful agents [learn more]

  • dramatically scaling task data collection to power reinforcement learning for SWE agents [learn more].

  • maximising efficiency of LLM training on agentic trajectories [learn more]

Our research demands a diverse, high-performance, scalable, and reliable infrastructure.

We are seeking a highly skilled and experienced Senior Software Engineer with Machine Learning background to join our dynamic team.

Your responsibilities will include:

  • Designing and developing infrastructure that powers our research, such as our framework for training and evaluating agents, data processing pipelines and complex workflows orchestrating multiple subsystems

  • Maximizing system performance, including optimizing LLM inference and efficiently orchestrating thousands of parallel agent runs.

  • Building web services to showcase and operationalize our research.

  • Owning a part of the system

We expect you to have:

  • 5+ years of professional software development experience, including prior work on Machine Learning projects

  • Strong software engineering skills (we mostly use Python)

  • Proficiency in contemporary software engineering approaches, including CI/CD, version control and unit testing.

  • A commitment to maintaining extreme rigor in all job-related activities, ownership and proactivity

Nice to have:

  • Previous experience with LLMs and agentic systems, inference solutions (e.g. vLLM), Machine Learning libraries (PyTorch, Jax, etc.)

  • Experience with Kubernetes and cloud environments, as well as DevOps-related skills

  • Familiarity with (big) data processing technologies, such as Spark/Hadoop (we use TractoAI/YTSaurus)

  • A track record of building and delivering infrastructure for large-scale Machine Learning systems

  • Hands-on skills with other programming languages, such as Go, C++, Rust.

What we offer

  • Competitive salary and comprehensive benefits package.
  • Opportunities for professional growth within Nebius.
  • Hybrid working arrangements.
  • A dynamic and collaborative work environment that values initiative and innovation.

We’re growing and expanding our products every day. If you’re up to the challenge and are excited about AI and ML as much as we are, join us!