Senior Machine Learning Engineer (ML Efficiency)

TL;DR

Senior Machine Learning Engineer (ML Efficiency): Building and optimizing training and inference systems for Ads ML to make them faster, cheaper, and more scalable with an accent on systems optimization and engineering leverage. Focus on diagnosing production bottlenecks, building performance tooling, and implementing model-level and infrastructure-level efficiency wins.

Location: Remote - United States

Salary: $216,700 - $303,400 USD

Company

Reddit is one of the internet's largest sources of information, hosting over 100,000 active communities with approximately 126 million daily active unique visitors.

What you will do

• Own high-value optimization initiatives across training and inference for Ads ML workloads.
• Diagnose production bottlenecks using profiling, benchmarking, and observability.
• Develop performance tooling, optimization playbooks, and efficiency primitives for multiple teams.
• Improve launch-safety through load testing, fallback readiness, and latency/cost visibility.
• Collaborate with model owners and platform teams to standardize repeated efficiency solutions.
• Mentor junior engineers in debugging, measurement rigor, and strong execution habits.

Requirements

• Deep experience with ML systems in real production environments and workloads.
• Proven track record of improving training or serving efficiency with measurable outcomes.
• Strong technical judgment across model-level, runtime-level, and infrastructure-level optimization.
• Ability to lead complex projects end-to-end and collaborate across team boundaries.
• Strong communication skills for explaining technical tradeoffs to partner teams.
• Must be based in the United States.

Nice to have

• Experience with GPU training or serving migrations.
• Proficiency with PyTorch, distributed training frameworks, or kernel/runtime optimization.
• Experience building launch certification, efficiency benchmarking, or cost observability systems.
• Knowledge of model compression (quantization, pruning, distillation, or checkpoint optimization).

Culture & Benefits

• Comprehensive healthcare benefits and income replacement programs.
• 401k program with employer match.
• Flexible vacation and paid volunteer time off.
• Generous paid parental leave and family planning support.
• Mental health, coaching, and gender-affirming care benefits.