Principal Engineer Frontend

Principal Engineer Frontend 37180 Westlake Village, California; Cary, North Carolina; Carrollton, Texas Technology $90,000 - $150,000 OFFICE or Job Description 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 homeownership through the complete mortgage journey. Job Overview As a Principal Frontend Engineer on the AI Platform Services team, you will be the architect of the platform's "face" and the guardian of the user experience. While the backend team builds the "brain" (RAG pipelines and autonomous agents), you will build the "Collaborative Canvas"—the interface where human ingenuity meets artificial intelligence. You will not just be building standard dashboards; you will be engineering complex, AI-native interfaces that rival commercial tools like Cursor and Linear. You will solve unique challenges in Generative UI, real-time state synchronization, and browser-based code editing. You will define how our engineers interact with autonomous agents, moving beyond simple "chatbots" to build a deeply integrated, multi-modal workspace that feels like a natural extension of the person's mind. This role requires a unique blend of elite frontend engineering, a deep understanding of developer tooling (IDEs, CI/CD interfaces), and a visionary approach to Human-Computer Interaction (HCI) in the age of AI. Why Join Pennymac? Chart Pennymac’s AI Course: This is a greenfield opportunity to join a foundational team and build a transformative platform from the ground up, with the stability and resources of an industry leader. Define the AI Interface: This is an opportunity to invent new UI patterns for "Agentic Workflows." You will move beyond static forms to build interfaces that generate themselves based on user intent and AI context. High-Impact & Visibility: Nexus is a top-priority strategic initiative. Your work will be the primary touchpoint for senior leadership and hundreds of engineers, directly impacting the "Idea-to-Production" velocity of the entire organization. Solve Unique Problems: You will tackle cutting-edge challenges in Collaborative Editing (CRDTs), Streaming UI, and Visualizing Complex Agent Reasoning—problems that sit at the bleeding edge of modern web development. Competitive Compensation: We offer a competitive salary, bonus, and benefits package, including comprehensive health/dental/vision plans, 401(k) matching, and more. Career Growth: We are committed to the growth of our team members and provide opportunities for continuous learning, professional development, and career advancement within a leading FinTech company. A Typical Day Architect the Agentic Workspace: Design and build the core frontend architecture for the AI platform using React, TypeScript, and Next.js, ensuring sub-second performance even with heavy data visualization and real-time streams. Build the "Collaborative Canvas": Engineer a real-time, multi-player workspace where AI agents and humans can co-author artifacts (User Stories, PRDs, Architecture Diagrams). Implement CRDTs (Conflict-Free Replicated Data Types) and WebSocket infrastructures to manage shared state seamlessly without data loss. Master the "Generative UI": Develop a robust component registry and rendering engine that allows AI agents to dynamically generate interactive UI elements (charts, forms, checklists) on the fly, rather than just outputting text. Visualize Intelligence: Create intuitive visualizations for the "Unified Context Library," allowing users to see why an AI agent made a decision, trace its sources (Jira, Confluence, GitLab), and inspect its reasoning graph via interactive diagrams. Partner with the Backend: Collaborate closely with Principal Backend Engineers to define the API contracts (GraphQL, Streaming JSON, Server-Sent Events) that enable the frontend to consume complex agent outputs efficiently. Developer Experience (DX) Leadership: Work directly with your "customers" (Pennymac engineers and product analysts) to understand their workflows. Translate their friction points into elegant UI solutions that reduce context switching. Establish Frontend Standards: Take ownership of the frontend DevOps pipeline, testing strategy (E2E/Integration), and architectural standards. Evangelize "AI-Native" design patterns across the broader technology organization. What You’ll Bring Must-Haves: Bachelor’s Degree in Computer Science, HCI, or related engineering disciplines, or equivalent professional experience. Elite Expertise in React & TypeScript: A proven track record (8+ years) of building complex, data-heavy Single Page Applications (SPAs). Deep mastery of React internals, hooks, context, and performance optimization. Next.js & Server Components: Experience with modern Next.js architectures (App Router), specifically leveraging Server Components and streaming for progressive UI rendering. Real-Time Collaboration Experience: Hands-on experience building multi-user, real-time applications using WebSockets, SSE, or libraries like Yjs, Automerge, or Liveblocks. You understand the complexities of state synchronization and conflict resolution in distributed systems. "Generative UI" / AI Integration: Demonstrable experience integrating LLM APIs (OpenAI, Anthropic, AWS Bedrock) into frontend applications. Experience with "streaming" UI responses and handling unstructured data. Data Visualization: Proficiency with visualization libraries (e.g., D3.js, Recharts, React Flow, or Mermaid.js) to render complex dependency graphs and architecture diagrams. A "Startup Mentality": High ownership, collaborative spirit, and adaptability. You are comfortable shipping an MVP "Collaborative Canvas" one week and refactoring it for scale the next based on user feedback. Nice-to-Have (Bonus Points): Experience with AI SDKs: Familiarity with the Vercel AI SDK, LangChain.js, or similar frameworks for managing agentic state in the frontend. Design Systems: Experience building or maintaining enterprise-grade Design Systems (e.g., using Tailwind CSS, Radix UI, or Shadcn). Backend Fluency: Ability to write Node.js/Edge Functions to support "Frontend-for-Backend" (BFF) patterns. Knowledge of ASTs: Understanding of Abstract Syntax Trees (ASTs) for code analysis and manipulation within the browser. FinTech/Mortgage Domain: Familiarity with the regulatory and compliance constraints of the financial industry (e.g., SOX, GLBA). Why You Should Join As one of the top mortgage lenders in the country, Pennymac has helped over 4 million lifetime homeowners achieve and sustain their aspirations of home. Our vision is to be the most trusted partner for home. Together, 4,000 Pennymac team members across the country are guided by our core values: to be Accountable, Reliable and Ethical in all that we do. Pennymac is committed to conducting a business that makes positive contributions and promotes long-term sustainable growth and to fostering an equitable and inclusive environment, where all employees and customers feel valued, respected and supported. Benefits That Bring It Home: Whether you're looking for flexible benefits for today, setting up short-term goals for tomorrow, or planning for long-term success and retirement, Pennymac's benefits have you covered. Some key benefits include: 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 style dining (select locations) Retirement benefits, life insurance, 401k match, and tuition reimbursement Philanthropy Programs including matching gifts, volunteer grants, charitable grants and corporate sponsorships To learn more about our benefits visit: https://pennymacnews.page.link/benefits For residents with state required benefit information, additional information can be found at: https://www.pennymac.com/additional-benefits-information Compensation: Individual salary may vary based on multiple factors including specific role, geographic location / market data, and skills and experience as defined below: Lower in range - Building skills and experience in the role Mid-range - Experience and skills align with proficiency in the role Higher in range - Experience and skills add value above typical requirements of the role Some roles may be eligible for performance-based compensation and/or stock-based incentives awarded to employees based on company and individual performance. Salary $90,000 - $150,000 Work Model OFFICE Apply Share This Job Pennymac is an equal opportunity employer. Pennymac values diversity and is committed to creating an inclusive environment for all employees. Pursuant to Pennymac’s Equal Employment Opportunity (EEO) policy, all qualified applicants will be considered without regard to any protected characteristic under state, federal, or local law, including, but not limited to race, color, creed, religion (including religious dress and grooming practices), age, sex (including pregnancy, childbirth, breastfeeding or related medical conditions), gender (including gender identity and gender expression), national origin (including language use or possession of a driver’s license issued under Vehicle Code § 12801.9), citizenship, ancestry, physical or mental disability, medical condition, genetic information, marital status, registered domestic partner status, sexual orientation, status as a victim of domestic violence, assault or stalking, military or veteran status, and/or political affiliation or activity. We encourage applications from all qualified candidates and will reasonably accommodate applicants’ needs in accordance with applicable law throughout all stages of the recruitment and selection process. If you need a reasonable accommodation to assist with your job search or application for employment, please contact us by sending an email to employeerelations@pennymac.com In your email please describe specific accommodation you are requesting and the position for which you are applying. Information received relating to accommodation will be addressed confidentially.

Salary : $90,000 - $150,000