# Senior Machine Learning Engineer
**Company:** [Retell AI](https://hotfix.jobs/companies/retell-ai)
**Location:** Redwood City, CA
**Salary:** $225K-$325K
**Skills:** PyTorch, Python, LLMs, Audio Models, Machine Learning, Model Training, Model Evaluation, Ml Pipelines, Human Evaluation, ML Infrastructure
**Posted:** 2025-10-16
> Builds and deploys production ML models for real-time voice AI agents, fine-tuning LLMs and audio models, running benchmarks and human evaluations, and maintaining ML infrastructure for high-scale performance.
## Job Description
## Key Responsibilities
- Train & Tune Models – Fine-tune LLMs and audio models to maximize speed, accuracy, and production-readiness—pushing the frontier of real-time AI voice experiences.
- Benchmark & Evaluate – Build datasets, define rigorous metrics, and measure model performance across high-impact voice AI tasks to guide development.
- Deploy to Production – Work closely with engineering to ship models, monitor them in the wild, and ensure they stay fast, reliable, and accurate at scale.
- Run Human Evaluations – Build scalable pipelines to collect structured human feedback, benchmark subjective quality, and inform model iterations.
- Level Up Infrastructure – Design and maintain the ML infrastructure needed for fast experimentation, robust training, and continuous deployment.

## Qualifications
- ML Engineer with Real-World Experience – You’ve trained and shipped models in production. **Bonus** if you’ve worked with LLMs or audio models.
- Fluent in Modern ML Stack – You know your way around **Python**, **PyTorch**, and today’s ML tools—from training pipelines to evaluation benchmarks.
- Execution-Oriented – You move fast, take ownership, and focus on solving real problems over perfect ones.
- Startup-Ready – You’re adaptable, resilient, and energized by ambiguity and fast-changing priorities.
- Clear Communicator & Team Player – You collaborate well across functions and push decisions forward.

## Compensation
**Cash**: $225,000 - $325,000 base salary  
**Equity**: Offers Equity
**Apply:** https://hotfix.jobs/jobs/senior-machine-learning-engineer-at-retell-ai-befa3407-396c-45b7-a9bd-66af0cd58088
**Canonical:** https://hotfix.jobs/jobs/senior-machine-learning-engineer-at-retell-ai-befa3407-396c-45b7-a9bd-66af0cd58088