# Research Scientist - LLM
**Company:** [Retell AI](https://hotfix.jobs/companies/retell-ai)
**Location:** Redwood City, CA
**Salary:** $225K-$400K
**Skills:** LLMs, PyTorch, Audio Models, Machine Learning, Model Architectures, Llm Pre-Training, Llm Post-Training, Transcription Models, Text-To-Speech, Multimodal Systems
**Posted:** 2026-04-14
> Conducts ML research to advance LLMs and audio models for real-time voice AI agents, focusing on reasoning, latency, and conversational quality. Prototypes models, designs evaluations, and bridges research to production systems requiring strong PyTorch expertise and experimental mindset.
## Job Description
## Key Responsibilities
- Research & Experimentation – Explore and develop new techniques across **LLMs** and **audio models** to improve reasoning, latency, and conversational quality in real-time systems.
- Model Prototyping – Rapidly build and iterate on experimental models and pipelines, turning research ideas into working prototypes.
- Evaluation & Benchmarking – Design novel evaluation frameworks, datasets, and metrics to measure performance on complex, real-world voice tasks.
- Bridge Research to Production – Collaborate closely with engineering to translate research insights into deployable systems.
- Human Feedback Loops – Develop methods to incorporate human evaluation into model improvement, especially for subjective conversational quality.
- Advance the Frontier – Stay at the cutting edge of ML research and bring new ideas into Retell’s product and infrastructure.

## You Might Thrive If You
- Strong ML Research Background – Worked on advanced ML problems (e.g., **LLM pre-training and post-training**, **transcription model training**, **text-to-speech model training**, or **multimodal systems**).
- Deep Technical Foundation – Comfortable with **PyTorch**, model architectures, and the math behind modern machine learning.
- Experimental Mindset – Enjoy exploring open-ended problems and iterating quickly on ideas.
- Bridging Theory & Practice – Translate research into systems that work in real-world environments.
- Startup-Ready – Thrive in fast-paced environments with high ownership and ambiguity.
- Collaborative & Clear Communicator – Explain complex ideas and work cross-functionally to drive impact.

## Compensation & Benefits
- **Cash**: $225,000 - $400,000 base salary
- **Equity**: Offers Equity
- **Location**: Redwood City, CA, US (100% Relocation Provided)
- 100% coverage for medical, dental, and vision insurance
- $70/day DoorDash credit for unlimited meals and snacks
- $200/month wellness reimbursement
- $300/month commuter reimbursement
- $75/month phone bill reimbursement
- $50/month internet reimbursement
**Apply:** https://hotfix.jobs/jobs/research-scientist-llm-at-retell-ai-e788a094-f375-428c-ab78-5a329d5fbfd0
**Canonical:** https://hotfix.jobs/jobs/research-scientist-llm-at-retell-ai-e788a094-f375-428c-ab78-5a329d5fbfd0