ReflectionAI

ReflectionAI

Member of Technical Staff - Pre-Training Infra

San Francisco · Staff+

H1B sponsorship availableDetected 119 days ago
Machine LearningA/B TestingResearchCommunication

About the role

  • Improve performance of distributed training workloads through optimization of communication, memory usage, and GPU utilization.
  • Debug and resolve performance bottlenecks across distributed training stacks including model parallelism, GPU communication, and training runtime systems.
  • Contribute to the development of systems that enable rapid experimentation and iteration on new training techniques.

Responsibilities

  • Reflection is a research lab making intelligence open and accessible for everyone to use, customize, and build on.
  • We build open models that let anyone control their intelligence and help shape the future of AI.
  • Build and scale distributed training systems that power frontier model pre-training.
  • Work closely with research teams to design and operate large-scale training runs for foundation models.
  • Collaborate directly with pre-training researchers to translate experimental ideas into scalable, production-ready training systems.
  • Build and maintain training pipelines that support large-scale datasets, checkpointing, and experiment iteration.
  • Sponsorship support: We sponsor visas to help exceptional talent join our team and support long-term immigration pathways where applicable.
  • Team building: We have regular off-sites, happy hours, and team celebrations.
  • Joining Reflection means building from the ground up as part of a talent-dense team.

Requirements

  • 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 such as NCCL and performance tuning for distributed workloads.
  • Experience working closely with ML researchers to productionize experimental training workflows.
  • Experience working with large datasets and training pipelines used for foundation model pre-training.

Skills

  • Strong experience working with modern distributed training frameworks such as Megatron, DeepSpeed, or similar large-scale training systems.
  • Strong debugging skills across GPU compute, distributed training systems, and large-scale ML pipelines

Compensation

  • Salary and equity structured to recognize and retain our talent globally.
  • Health & wellness: Comprehensive medical, dental, vision, and life, with an annual wellness allowance.

Benefits

  • Top-tier compensation: Salary and equity structured to recognize and retain our talent globally.
  • Stock options: Everyone who joins and contributes to Reflection's success gets to share in the upside through stock options.
  • Health & wellness: Comprehensive medical, dental, vision, and life, with an annual wellness allowance.
  • Life & family: 22 weeks paid parental leave for all new birthing and non-birthing parents, including adoptive and surrogate journeys.
  • Vacation days: Unlimited paid time off in the U.S. and 30 days in the U.K.

Company info

  • make intelligence open and accessible to all.

Visa & Work Authorization

  • We sponsor visas to help exceptional talent join our team and support long-term immigration pathways where applicable.

This listing is sourced directly from ReflectionAI's careers page and normalized into a canonical job model.