Member of Technical Staff - Research Software Engineer

About the role

The Roles at Our Mission Reflection bridge the gap between research and production by transforming cutting-edge algorithms into scalable training systems. This team owns and evolves the core infrastructure behind our training systems, focusing on reinforcement learning training loops, distributed GPU systems, and large-scale data pipelines.

Responsibilities

• Designing and optimizing large-scale training loops and data pipelines.
• Implementing state-of-the-art techniques and ensuring they are numerically stable and computationally efficient.
• Building internal tooling for launching, monitoring, and reproducing complex experiments.
• Diagnosing deep bottlenecks across the training stack (GPU memory issues, communication overhead, dataloader stalls).
• Translating research prototypes into reusable, production-grade infrastructure.

What This Team Does

• Distributed Training
• GPU parallelism (data, tensor, pipeline, expert)
• Communication optimization (NCCL, RDMA, GPU interconnects)
• FSDP / ZeRO and model sharding
• Orchestration & Runtime Systems
• Ray, Kubernetes, Slurm
• Distributed runtimes and async systems
• Containerization and sandboxing
• Frameworks
• PyTorch, JAX, Megatron-style training stacks, Triton / custom kernels
• Data Infrastructure
• Large-scale dataset curation pipelines
• Deduplication and filtering systems
• Tokenization and preprocessing
• Distributed data processing frameworks

About You

• You are a strong software engineer who speaks the language of machine learning.
• You may not have a PhD, but you know how to implement a research paper.
• You have deep experience in at least one of the following: Distributed Training & Inference or Data Infrastructure.
• You enjoy working at the boundary between: Machine learning algorithms, Distributed systems, High-performance computing.
• You care deeply about performance, numerical stability, and reproducibility.
• You thrive in high-agency environments and enjoy solving hard technical problems.

What We Offer

• 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.
• Meals: Lunch and dinner are provided in the office daily.
• 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.
• 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.