[Hiring] Principal Engineer, LLM @Upstart

Role Description

As a Principal Engineer - GenAI/LLM, you will provide technical leadership across multiple cross-functional teams, shaping the vision, architecture, and adoption strategy for our new GenAI platform for Engineers and non-Engineers alike.

• Define and drive the multi-year technical roadmap for the Core GenAI Platform, influencing adoption and alignment across several engineering teams.
• Collaborate with CTO/VP-level and above leadership to influence business strategy with technical insight.
• Lead architecture and design of large-scale, mission-critical systems for model inference, orchestration, and compliance.
• Identify and solve systemic technical risks that impact the entire company and business-critical AI initiatives.
• Represent Upstart internally and externally as a thought leader in GenAI systems through executive reviews, cross-company forums, and industry venues.
• Establish operational standards for GenAI integrations, ensuring security, fairness, and reliability at scale.
• Build high-leverage, generalizable platform components that meaningfully accelerate the productivity of engineers across Upstart.
• Mentor senior engineers, other principal engineers, and shape the growth of future technical leaders, fostering a culture of learning and excellence.

Qualifications

• Bachelor’s degree in Computer Science, Engineering, or Mathematics, or a related field (or its equivalent) + 8 years of experience.
• Deep expertise in LLM-specific infrastructure such as inference optimization (quantization, ONNX, streaming).
• Ability to design scalable RAG architectures and manage the lifecycle of models from experimentation to high-availability production environments including vector databases.
• Proven experience building robust, automated evaluation pipelines using both heuristic metrics and 'LLM-as-a-judge' frameworks to ensure model accuracy and safety.
• Hands-on experience with LLM toolchains such as LangChain, LlamaIndex, or OpenAI APIs.
• Experience designing and operationalizing ML/LLM platforms at scale, including optimization for cost, latency, and reliability and the platform infrastructure needed to support them.
• Deep Expertise in best practices and risks for GenAI including hallucination mitigation, fairness, explainability, and data privacy.

Requirements

• 12+ years of experience and 5+ leading cross-functional technical initiatives.
• Proven ability to execute or guide model fine-tuning and alignment (RLHF/DPO) to optimize LLM performance for specialized consumer use cases and proprietary datasets.
• Full-stack engineering experience (Python, FastAPI, Kotlin, Spring, React/TypeScript, or similar).
• Deep expertise in backend systems and infrastructure technologies such as Kubernetes, Docker, Terraform, and cloud-native architectures.

Benefits

• Competitive compensation, including base pay, bonus opportunities, and annual equity grants that vest quarterly.
• Generous 401(k) plan with Upstart matching $2 for every $1 contributed, up to $15,000 per year.
• Employee Stock Purchase Plan (ESPP) with discounted stock purchase options for eligible employees.
• Affordable medical, dental, and vision coverage, with multiple plan options - Upstart covers 90% to 100% of the cost depending on the plans you choose.
• Health Savings Account contributions from Upstart for eligible plans.
• Income protection benefits, including company-paid Basic Life, AD&D, and Short- and Long-Term Disability coverage, with options to purchase supplemental coverage.
• Paid time off, sick and safe time, and company holidays.
• Paid family and parental leave to support caregiving and major life moments.
• Family-centered benefits through Carrot and Cleo, supporting fertility, parenthood, and caregiving.
• Employee Assistance Program (EAP) offering mental health support and life-centered resources.
• Financial wellness resources, including access to financial planning tools and a financial concierge service.
• Annual wellness allowance to support your physical and emotional well-being and personal development, based on what matters most to you.
• Annual productivity allowance to invest in relevant tools and resources you need to do your best work, no matter where you work from.
• Connection and community through team events and onsites, all-company updates, and employee resource groups (ERGs).
• Onsite perks, including catered lunches and fully stocked micro-kitchens when working from one of our four offices, located in the Bay Area, Austin, Columbus, and New York City (opening Summer 2026!).