Founding Applied AI Engineer

Kastle is building AI operating system for consumer lending, starting with mortgage. We work with some of America's largest mortgage lenders, helping them scale their contact center and compliance operations using AI-driven voice agents. Backed by $2.3M from Y Combinator, Commerce Ventures, and executives from Snapdocs, Google, and WePay, we are redefining lending with AI.

As a Founding Applied AI Engineer, you'll be instrumental in building the technical foundation of Kastle's AI platform. You'll fine-tune large language models, design AI workflows for highly regulated enterprises, and ensure our voice agents deliver precise, compliant, and effective borrower interactions.

This role is ideal for an engineer who is passionate about applied AI, eager to solve real-world challenges, and excited to build the technical foundation of an early-stage AI startup.

AI Model Integration: Fine-tune and deploy LLMs for real-time voice-based borrower interactions

Prompt Engineering: Design and iterate on prompt strategies to optimize AI performance and compliance

Evaluate LLMs and AI Agents: Build high quality evals using our proprietary datasets to benchmark AI agent performance and run experiments