Senior Machine Learning Engineer

About the Company

Retell AI is using first principles to reimagine the call center with cutting-edge voice AI. Backed by Y Combinator and Alt Capital, we have scaled to $60M ARR and are building a modern CX platform where entire contact centers are powered by intelligent AI workers.

Responsibilities

• Train & Tune Models: Fine-tune LLMs and audio models to maximize speed, accuracy, and production-readiness
• Benchmark & Evaluate: Build datasets, define rigorous metrics, and measure model performance across voice AI tasks
• Deploy to Production: Ship models, monitor them in the wild, and ensure reliability at scale
• Run Human Evaluations: Build scalable pipelines to collect structured human feedback to inform model iterations
• Level Up Infrastructure: Design and maintain ML infrastructure for fast experimentation and continuous deployment

Requirements

• Experience training and shipping models in production
• Proficiency with Python and PyTorch
• Experience with modern ML tools, training pipelines, and evaluation benchmarks
• Ability to thrive in a fast-paced startup environment

Preferred Qualifications

• Experience working specifically with LLMs or audio models

Benefits

• $225,000 - $325,000 base salary plus equity
• 100% coverage for medical, dental, and vision insurance
• $70/day DoorDash credit
• $200/month wellness reimbursement
• $300/month commuter reimbursement
• $75/month phone bill reimbursement
• $50/month internet reimbursement