Senior Machine Learning Engineer, LLM Inference Optimization

Nebius; Palo Alto (CA); Hybrid; USD 195,200 - 262,200; Full time

Benefits offered by this job

Health insurance

401(k) plan

Parental leave

Remote work reimbursement

Disability & life insurance

Job summary

Nebius in Palo Alto is seeking a Senior MLE to own end-to-end model and endpoint optimization. You will work at the intersection of distributed systems, GPU performance, and production ML engineering, debugging serving problems and delivering measurable improvements with minimal supervision.

You will deploy and optimize LLM/VLM backends, quantify latency and cost, and collaborate with researchers, kernel engineers, and platform teams to push the performance frontier of AI workloads.

Qualifications

• Strong Python and PyTorch engineering skills.
• Hands-on experience deploying or optimizing LLM/VLM systems.
• Experience with modern inference stacks such as vLLM, Triton, TensorRT-LLM, etc.
• Strong understanding of transformer inference bottlenecks.
• Ability to reason quantitatively about latency, throughput, cost, and quality tradeoffs.
• Strong communication and collaboration with research, kernel, infrastructure, product, and customer teams.

Responsibilities

• Own optimization work for specific model families, endpoints, or serving backends.
• Run engine comparisons and recommend practical serving configurations for specific workloads.
• Debug model quality or performance regressions during production rollouts.
• Optimize LLM and VLM endpoints for latency, throughput, memory efficiency, GPU utilization, quality, and cost per token.
• Deploy, configure, benchmark, and extend inference engines such as vLLM, SGLang, TensorRT-LLM, Triton Inference Server, NVIDIA Dynamo, or similar systems.
• Build and productionize model-compression workflows, including quantization, quantization-aware training, distillation, low-bit serving, and accuracy recovery.
• Implement or integrate speculative decoding, draft-model approaches, KV-cache optimization, prefix caching, chunked prefill, continuous batching, and disaggregated prefill/decode serving.
• Build reproducible benchmark harnesses for TTFT, TPOT, tokens per second per GPU, p95/p99 latency, GPU memory, reliability, and cost per token.
• Partner with GPU kernel engineers and platform engineers to diagnose bottlenecks across model code, kernels, runtime, scheduler, gateway, and cluster layers.
• Write clear design docs, performance reports, rollout plans, and customer-facing technical explanations.

Skills

Python

PyTorch

Distributed systems

LLM deployment

Model optimization

RL pipelines

Tools

vLLM

SGLang

TensorRT-LLM

Triton Inference Server

NVIDIA Dynamo

Ray Serve

KServe

Job description

About Nebius

Nebius is leading a new era in cloud infrastructure for the global AI economy. We are building a full-stack AI cloud platform that supports developers and enterprises from data and model training through to production deployment, without the cost and complexity of building large in-house AI/ML infrastructure.

Built by engineers, for engineers. From large-scale GPU orchestration to inference optimization, we own the hard problems across compute, storage, networking and applied AI.

Listed on Nasdaq (NBIS) and headquartered in Amsterdam, we have a global footprint with R&D hubs across Europe, the UK, North America and Israel. Our team of 1,500+ includes hundreds of engineers with deep expertise across hardware, software and AI R&D.

The role

Nebius Token Factory is building an AI training and model post-training capability for frontier model improvement. This role owns the infrastructure that makes large-scale training and RL experiments possible, reliable, reproducible, and efficient. The work sits at the intersection of distributed systems, GPU performance, model training frameworks, RL pipelines, and production engineering.

A Senior MLE owns substantial model and endpoint optimization projects end to end. They are deeply hands‑on, can debug difficult serving problems independently, and can deliver measurable improvements without needing heavy supervision.

Your Responsibilities

• Own optimization work for specific model families, customer endpoints, or serving backends.
• Run engine comparisons and recommend practical serving configurations for specific workloads.
• Debug model quality or performance regressions during production rollouts.
• Optimize LLM and VLM endpoints for latency, throughput, memory efficiency, GPU utilization, quality, and cost per token.
• Deploy, configure, benchmark, and extend inference engines such as vLLM, SGLang, TensorRT-LLM, Triton Inference Server, NVIDIA Dynamo, or similar systems.
• Build and productionize model-compression workflows, including quantization, quantization‑aware training, distillation, low‑bit serving, and accuracy recovery.
• Implement or integrate speculative decoding, draft-model approaches, KV‑cache optimization, prefix caching, chunked prefill, continuous batching, and disaggregated prefill/decode serving.
• Build reproducible benchmark harnesses for TTFT, TPOT, tokens per second per GPU, p95/p99 latency, GPU memory, reliability, and cost per token.
• Partner with GPU kernel engineers and platform engineers to diagnose bottlenecks across model code, kernels, runtime, scheduler, gateway, and cluster layers.
• Write clear design docs, performance reports, rollout plans, and customer‑facing technical explanations.

Must-haves

• Strong Python and PyTorch engineering skills.
• Hands‑on experience deploying or optimizing LLM, VLM, or high‑throughput transformer inference systems.
• Practical knowledge of at least one modern inference stack such as vLLM, SGLang, TensorRT-LLM, Triton Inference Server, NVIDIA Dynamo, Ray Serve, KServe, or equivalent internal systems.
• Strong understanding of transformer inference bottlenecks, including KV cache, attention, memory bandwidth, batching, parallelism, and long‑context serving.
• Ability to reason quantitatively about latency, throughput, quality, utilization, and cost tradeoffs.
• Strong communication skills and ability to collaborate with research, kernel, infrastructure, product, and customer teams.

Nice-to-haves

• Experience with quantization‑aware training, post‑training quantization, FP8, INT8, INT4, NVFP4, MXFP4, AWQ, GPTQ, SmoothQuant, or related techniques.
• Experience with distillation, speculative decoding, EAGLE, Medusa, multi‑token prediction, or other inference acceleration methods.
• Experience with agentic workloads, including tool calling, structured outputs, streaming APIs, high concurrency, and multi‑step orchestration.
• CUDA or Triton familiarity, even if the role is not primarily a kernel‑engineering role.
• Open‑source contributions to vLLM, SGLang, TensorRT-LLM, FlashInfer, LMCache, PyTorch, Triton, Ray, KServe, or related projects.

Key Employee Benefits In The US

• Health insurance: 100% company‑paid medical, dental, and vision coverage for employees and families.
• 401(k) plan: Up to 4% company match with immediate vesting.
• Parental leave: 20 weeks paid for primary caregivers, 12 weeks for secondary caregivers.
• Remote work reimbursement: Up to $85/month for mobile and internet.
• Disability & life insurance: Company‑paid short‑term, long‑term and life insurance coverage.

Pay Transparency

We offer competitive compensation and benefits packages. Actual compensation will be determined based on job-related factors, including experience, skills, qualifications, the level at which the candidate is hired, and geographic location, consistent with applicable law.

Base Compensation Range

$195,200—$262,200 USD

Benefits & Perks

• Competitive compensation
• Career growth and learning opportunities
• Flexibility and ownership
• Collaborative and innovative culture
• Opportunity to work on impactful AI projects
• International environment and talented teams

What's It Like To Work At Nebius

Fast moving - Bold thinking - Constant growth - Meaningful impact - Trust and real ownership - Opportunity to shape the future of AI

Equal Opportunity Statement

Nebius is an equal opportunity employer. We are committed to fostering an inclusive and diverse workplace and to providing equal employment opportunities in all aspects of employment. We do not discriminate on the basis of race, color, religion, sex (including pregnancy), national origin, ancestry, age, disability, genetic information, marital status, veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by applicable law.

Applicants must be authorized to work in the country in which they apply and will be required to provide proof of employment eligibility as a condition of hire.

If you need accommodations during the application process, please let us know.