Research Engineer, Applied Research
Core
Advancing the quality, speed, and cost efficiency of models powering customer-facing AI agents through post-training and voice AI research.
Role type
Senior Applied Research Engineer (AI/ML)
Builds
Production-ready AI agents capable of reasoning, adapting, and executing complex long-horizon tasks.
Domain
Generative AI, Voice AI, Post-training, Reinforcement Learning
Deliverable
production ML models
Required skills
Production ML system deployment, Problem framing for ML, Data experimentation and evaluation, Model iteration, Cross-stack execution
Preferred skills
Supervised fine-tuning, Reinforcement learning, Search/ranking/recommendations systems, Language/speech/multimodal model training, Real-world product outcome evaluation, Large-scale consumer dataset experience
Technologies
Proprietary text and audio interaction datasets (via careerplan.io/jobs/ddae4a0c-2f6c-4cc3-80aa-da74a0dd667a-research-engineer-applied-research-at-sierra)
Responsibilities
Tackle unsolved applied AI and ML problems to build agents that reason and adapt; Determine when to build specialized models vs. use external frontier intelligence; Turn ambiguous product problems into well-framed ML problems; Develop, fine-tune, evaluate, and deploy models for customer-facing agents; Advance post-training work from supervised fine-tuning to reinforcement learning; Build rigorous evaluations connecting model performance to real-world agent quality; Collaborate across teams to take ideas from experimentation to production deployment.
