Principle Applied AI Engineer

Overview

PENNYMAC Pennymac (NYSE: PFSI) is a specialty financial services firm with a comprehensive mortgage platform and integrated business focused on the production and servicing of U.S. mortgage loans and the management of investments related to the U.S. mortgage market.

At Pennymac, our people are the foundation of our success and at the heart of our dynamic work culture. Together, we work towards a unified goal of helping millions of Americans achieve aspirations of home ownership through the complete mortgage journey.

Job Overview:
As the Principal Applied AI Engineer, you will be the lead architect of the "cognitive" layer of the AI platform. You will design the autonomous workflows that turn a Product Manager’s idea into a technical specification and a User Story into deployable code. This role sits at the intersection of elite software engineering and applied artificial intelligence.

You will not be training foundational models from scratch; rather, you will master Applied AI in orchestration, retrieval-augmented generation (RAG), and the engineering of agentic systems using the AWS Bedrock Agent Core framework. You will work within the AI Platform Services division, a dedicated R&D unit tasked with delivering measurable velocity improvements to the entire organization.

• Architect the Future of SDLC:
  You will build the "Agent Factory" that drives our "conveyor belt" of software delivery, moving us from a reactive to a proactive engineering culture.
• Greenfield Innovation:
  Build an enterprise-grade AI platform from the ground up, leveraging the latest in AWS Bedrock Agent Core and Agentic AI frameworks.
• High-Impact & Visibility:
  Your work will directly impact the daily lives of hundreds of engineers and product owners, reducing "Idea-to-MR" cycle times and eliminating manual toil.
• Cutting-Edge Stack:
  Work with a modern, cloud-native stack (AWS, Node.js/Type Script) specifically tailored for high-performance AI applications.

• Elite Engineering Core:
  Bachelor’s Degree in Computer Science or equivalent, with 8+ years of professional software engineering experience. You are a software engineer first, who has mastered AI tools.
• Type Script/Node.js Expert:
  Deep expertise in building backend services and AI chains in this ecosystem.
• Applied AI & Agent
  
  Experience:
  
  Hands-on experience building applications powered by LLMs using frameworks like Lang Chain, Strands, or AWS Bedrock.
• RAG Mastery:
  Production-grade RAG systems with embeddings, vector stores (Pinecone, Milvus), and semantic search.
• Cloud Native (AWS):
  
  Experience with AWS serverless architecture (Lambda, API Gateway, Dynamo
  
  DB). Familiarity with AWS Bedrock and Agent Core is a plus.
• Systems Thinking:
  Design of complex, asynchronous systems with probabilistic outcomes.
• Startup Mentality:
  High ownership and energy to thrive in a fast-paced internal startup environment.

• Experience with Evaluation Frameworks (e.g., Lang Smith, Ragas) for automated testing of LLM outputs.
• Familiarity with Model Context Protocol (MCP) for standardizing AI tool connections.
• Background in Developer Tools (CLI tools, IDE plugins, CI/CD automations).
• Understanding of Graph Databases (e.g., Neo4j) for knowledge graphs alongside vector search.

Pennymac has helped over 4 million lifetime homeowners. Our vision is to be the most trusted partner for home. With 4,000 Pennymac team members, we are guided by our core values:
Accountable, Reliable and Ethical. Pennymac is committed to equitable and inclusive environment where all employees and customers feel valued, respected and supported.

• Comprehensive Medical, Dental, and Vision
• Paid Time Off Programs including vacation, holidays, illness, and parental leave
• Wellness Programs, Employee Recognition Programs, and onsite gyms and cafe dining (select locations)
• Retirement benefits, life insurance, 401k match, and tuition reimbursement
• Philanthropy Programs including matching gifts, volunteer grants, charitable grants and corporate sponsor ships

Compensation:
Individual salary may vary based on role, location, and experience. Salary: $90,000 - $150,000. Work Model: OFFICE