Member of Technical Staff - Pre-Training Infra

San Francisco, CA • FullTime

Posted 6mo ago

Remote Work Policy

On-site

Employment Type

FullTime

Categories

Machine Learning Engineer

About the job

Reflection is a research lab dedicated to making intelligence open and accessible. We build open models that empower individuals to control their intelligence and shape the future of AI. As a Member of Technical Staff - Pre-Training Infra, you will be instrumental in building and scaling the distributed training systems that power frontier model pre-training. This role involves close collaboration with research teams to design and operate large-scale training runs for foundation models, and developing the infrastructure necessary for efficient training across thousands of GPUs.

Responsibilities

  • Build and scale distributed training systems for frontier model pre-training.
  • Design and operate large-scale training runs for foundation models in collaboration with research teams.
  • Develop infrastructure for efficient training across thousands of GPUs using distributed training frameworks.
  • Optimize training throughput, stability, and efficiency for large model training workloads.
  • Translate experimental ideas into scalable, production-ready training systems with pre-training researchers.
  • Improve performance of distributed training workloads by optimizing communication, memory usage, and GPU utilization.
  • Build and maintain training pipelines for large-scale datasets, checkpointing, and experiment iteration.
  • Debug and resolve performance bottlenecks in distributed training stacks, including model parallelism, GPU communication, and training runtime systems.
  • Contribute to systems enabling rapid experimentation and iteration on new training techniques.

Requirements

  • Experience building or operating distributed training systems for large machine learning models.
  • Strong experience with modern distributed training frameworks (e.g., Megatron, DeepSpeed).
  • Familiarity with large-scale model parallelism strategies (data, tensor, pipeline, or expert parallelism).
  • Experience optimizing training throughput and GPU utilization in large distributed environments.
  • Familiarity with GPU communication libraries (e.g., NCCL) and performance tuning for distributed workloads.
  • Experience collaborating with ML researchers to productionize experimental training workflows.
  • Strong debugging skills across GPU compute, distributed training systems, and large-scale ML pipelines.
  • Experience with large datasets and training pipelines for foundation model pre-training.

Benefits

  • Top-tier compensation (salary and equity)
  • Stock options
  • Comprehensive medical, dental, vision, and life insurance
  • Annual wellness allowance
  • Provided lunch and dinner in the office
  • 22 weeks paid parental leave
  • Unlimited paid time off (U.S.)
  • 30 days paid time off (U.K.)
  • Visa sponsorship support
  • Regular off-sites, happy hours, and team celebrations

About Reflection ai

Get new AI jobs in your inbox

A weekly digest of the newest AI engineering roles.

© 2026 AI Job Board. All rights reserved.