ML Systems Engineer - AI Trainer

Mercor; Chicago (IL); On-site; USD 120,000 - 180,000; Full time

Job summary

Join a leading AI lab's GenAI team as an MLOps Engineer, building foundational AI models and maintaining LLM infrastructure across GPU kernels, profiling, and inference serving. You will contribute to training data and evaluation tasks, aligning with frontier AI systems.

This 40-hour full-time engagement is a W-2 position with Cincinnatus LLC, offering placement at a leading AI Lab as part of an extended workforce with no conflicts or other engagements.

Qualifications

• 2+ years hands-on experience in ML systems, ML infrastructure or model serving.
• Experience in at least one area: GPU kernels, profiling, debugging, or large language model serving.
• Production experience with JAX and/or PyTorch; depth in operators, distributed training or compiler work.
• Familiar with accelerators like A100/H100/TPU and memory/latency trade-offs.
• Demonstrated career progression and reliable 40+ hours/week availability.
• Strong written communication and ability to explain complex technical decisions.

Responsibilities

• Design tasks across GPU kernels, profiling, debugging, and inference serving.
• Guide teams to close knowledge gaps and improve AI model performance on ML systems.
• Evaluate MLOps tasks and provide clear technical feedback.
• Develop evaluation frameworks for kernel optimization, profiling, and serving latency.
• Collaborate with experts to maintain training data consistency.

Skills

MLOps

ML systems

GPU kernels

Performance profiling

Distributed workloads

LLM infrastructure

Tools

CUDA

Triton

Pallas

Kineto

Nsight

JAX profiler

PyTorch

TensorRT-LLM

Job description

Join a leading AI lab's cutting-edge GenAI team to be at the core of the AI revolution, where your expertise fuels the development of the most advanced Large Language Models.

1. Overview

Join a leading AI lab's cutting-edge GenAI team and help build foundational AI models from the ground up. We're seeking MLOps Engineers with hands-on experience in large language model infrastructure across any of four areas: GPU kernel programming, performance profiling and trace analysis, debugging accelerated and distributed workloads, and high-throughput inference serving. This role involves AI model training and evaluation work, including writing and assessing MLOps and ML systems tasks and solutions to generate high-quality training data for frontier AI systems.

This is a W-2 employment position with Cincinnatus LLC, with the opportunity to be placed at a leading AI Lab as part of their extended workforce. This is a 40-hour full-time engagement, with no conflicts/no other engagements.

2. Key Responsibilities

• Design challenging, domain-relevant tasks across four areas, GPU kernels, performance profiling, debugging, and inference serving, and write accurate, well-structured solutions to them.

• Guide research and engineering teams to close knowledge gaps and improve AI model performance on ML systems, training infrastructure, and framework-level topics.

• Evaluate MLOps and ML systems tasks and solutions, and provide clear, written technical feedback that stands up to reviewer scrutiny.

• Develop guidelines and detailed rubrics or evaluation frameworks covering kernel-level optimization, profiler output interpretation, distributed systems reasoning, and serving throughput and latency trade-offs.

• Collaborate with other subject matter experts to keep training data consistent and accurate.

3. Core Qualifications

• 2+ years of hands-on professional experience in ML systems, ML infrastructure, model serving, or GPU and accelerator performance engineering. This is a hands-on systems role rather than an applied modelling or data science one.

• Practical experience in at least one of the following, with more than one a strong plus: writing or optimizing custom GPU kernels (CUDA, Triton, Pallas); performance profiling and trace analysis (Kineto, torch.profiler, Nsight, XLA or JAX profiler); debugging distributed or accelerator-bound workloads; serving large language models at scale (vLLM, SGLang, TensorRT-LLM, Ray Serve, KV cache, paged attention, continuous batching).

• Working production experience with JAX and/or PyTorch. Framework-level depth is a strong plus: custom operators, distributed training (FSDP, DDP, DeepSpeed, Megatron), or compiler and graph-level work.

• Familiarity with modern accelerators such as A100, H100, B200 or TPU, and the ability to reason about throughput, latency and memory trade-offs.

• Demonstrable career progression.

• Ability to engage reliably for at least 40 hours/week during weekdays.

• Strong written communication skills and the ability to explain complex technical decisions clearly.

About Cincinnatus LLC:Cincinnatus LLC is an enterprise staffing company that partners with leading technology companies to source and employ highly skilled professionals for contingent and contract-based opportunities. Cincinnatus serves as the employer of record for these engagements, providing W-2 employment, payroll, benefits, and compliance, while placing employees directly within client teams to work on high-impact initiatives.

Equal Employment Opportunity: Cincinnatus is proud to be an Equal Employment Opportunity employer. We do not discriminate based upon race, religion, color, national origin, sex (including pregnancy, childbirth, reproductive health decisions, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, political views or activity, or any other legally protected characteristic.