Research Scientist - LLM

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

• Explore and develop new techniques across LLMs and audio models to improve reasoning, latency, and conversational quality.
• Rapidly build and iterate on models and pipelines, turning research ideas into working prototypes.
• Design novel evaluation frameworks, datasets, and metrics to measure performance on complex, real-world voice tasks.
• Collaborate closely with engineering to translate research insights into deployable systems.
• Develop methods to incorporate human evaluation into model improvement.

Requirements

• Strong ML Research Background in LLM pre-training, post-training, transcription, TTS, or multimodal systems.
• Deep technical foundation in PyTorch, model architectures, and machine learning mathematics.
• Master's degree in CS, ML, AI or related field (PhD preferred).

Preferred Qualifications

• Published or co-authored papers at top-tier venues like NeurIPS, ICML, ICLR, ACL, or Interspeech.
• Ability to translate theoretical research into real-world production systems.
• Experience thriving in fast-paced, high-ownership startup environments.