Research Engineer (LLM Training and Performance)

At JetBrains, code is our passion. Ever since we started back in 2000, we have been striving to make the strongest, most effective developer tools on earth. By automating routine checks and corrections, our tools speed up production, freeing developers to grow, discover, and create.

We’re looking for a Research Engineer who will own the training stack and model architecture for our Mellum LLM family. Your job is easier said than done: make training faster, cheaper, and more stable at a large scale. You’ll profile, design, and implement changes to the training pipeline – from architecture to custom GPU kernels, as needed.

As Part Of Our Team, You Will

• Be responsible for improving end-to-end performance for multi-node LLM pre‑training and post‑training pipelines.
• Profile hotspots (Nsight Systems/Compute, NVTX) and fix them using compute/comm overlap, kernel fusion, scheduling, etc.
• Design and evaluate architecture choices (depth/width, ...