# Staff AI Engineer

**Company:** [Kastle](https://hotfix.jobs/companies/kastle)
**Location:** San Francisco, CA
**Role:** ML Engineering
**Salary:** $180k – $250k/yr
**Skills:** Python, PyTorch, TensorFlow, LangChain, Llamaindex, LLMs, Prompt Engineering, Machine Learning, Deep Learning, AI Agents
**Posted:** 2025-11-22

> Builds and deploys fine-tuned LLMs and AI agents for real-time voice interactions in consumer lending, ensuring compliance and scalability. Requires 2+ years production ML/AI experience with Python, PyTorch/TensorFlow, and LLM frameworks.

## Job Description

## What You'll Do
- **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
- **Custom AI Solutions**: Train and implement domain-specific AI models for consumer lending
- **Scalability & Compliance**: Ensure AI solutions meet regulatory standards (FDCPA, RESPA, TILA) and scale efficiently
- **Data Pipelines & APIs**: Build robust AI-driven workflows that integrate seamlessly with loan servicing platforms
- **Continuous Optimization**: Monitor performance metrics and continuously improve agent quality and borrower experience

## What We're Looking For
- 2+ years building and deploying ML/AI systems in production environments
- Strong proficiency in Python and deep learning frameworks (**TensorFlow**, **PyTorch**)
- Experience with LLM orchestration frameworks (**LangChain**, **LlamaIndex**, or similar)
- Track record of shipping AI products that real users depend on
- Strong product mindset and ability to translate business requirements into AI solutions
- Excellent communication skills to collaborate across product, engineering, and compliance teams

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**Apply:** https://hotfix.jobs/jobs/3f2c9671-572d-40d4-85ee-d72543592786
**Canonical:** https://hotfix.jobs/jobs/3f2c9671-572d-40d4-85ee-d72543592786