Principal Applied AI / ML Engineer

About FaireFaire is a technology wholesale platform built on the belief that the future is local. Independent retailers around the globe collectively represent a multi-hundred-billion-dollar wholesale market that has historically been fragmented and offline. At Faire, we're using the power of tech, data, and machine learning to connect this thriving community of entrepreneurs across the globe. Picture your favorite boutique in town — we help them discover the best products from around the world to sell in their stores. With the right tools and insights, we believe that we can level the playing field so businesses can grow and local communities can thrive.We’re looking for smart, resourceful and passionate people to join us as we power the shop local movement. If you believe in community, come join ours.About this role:We are seeking a Principal AI / ML Engineer to be a company-level technical thought leader and practitioner to help shape the future of Data and AI at Faire. This is a rare opportunity to drive broad technical strategy across data, engineering, and product while remaining deeply hands-on with cutting-edge AI research and applications. This role reports directly to the CTO of Faire.You will:Shape the AI vision – Partner with product, design, strategy & analytics, machine learning, and the broader engineering leadership to define how AI can deliver transformational value to Faire’s retailers and brands. Offer thought leadership to shape company-wide priorities, with particular focus on product strategy and key investment directions.Prototype and unblock – Build and lead deployment of AI systems (LLM fine-tuning, RLHF, agent frameworks, etc.) that demonstrate what’s possible and accelerate adoption across teams. Act as a “super IC” who can dive deep to remove technical barriers, enabling the engineering organization to move quickly with AI and accelerate both development and impact.Architect the AI-ready stack – Shape the design of Faire’s technical ecosystem — spanning event logging, data warehouses, feature stores, and model serving — to ensure our infrastructure is AI-ready, scalable, and optimized for rapid experimentation and the safe & reliable deployment of innovative AI-enabled features.What you’ll do:Serve as a trusted partner to executives and senior leaders, informing long-term strategy and product direction for AI-enabled experiences.Prototype and deploy cutting-edge AI systems using LLMs, generative AI, and agentic frameworks — taking concepts from zero-to-one and helping teams productionize them.Define technical standards and evaluation frameworks for safety, reliability, and business impact of AI features.Partner with infrastructure and platform teams to evolve Faire’s data pipelines, ML serving stack, and developer tools for AI-driven velocity.Mentor engineers and scientists across the org, raising the technical bar through coaching, tooling, knowledge sharing, and design reviews.Evangelize AI best practices and foster a culture of innovation that balances bold experimentation with pragmatic delivery.Who you are:10+ years of experience training and deploying machine learning models at scale, conducting applied AI research, and productizing advanced AI/ML technologies for impact.Proven track record of delivering production-grade AI systems at scale and influencing product strategy. Great at operating at the intersection of tech and product.Deep expertise in LLMs and modern AI techniques: fine-tuning, RLHF, RAG, embeddings, and agent frameworks.Strong systems background: experience with large-scale data pipelines, ML feature stores, distributed training, and model serving infrastructure.Proficiency with PyTorch, TensorFlow, JAX, Triton, or other relevant AI development and production frameworks.Exceptional communication and influence skills — able to collaborate with executives and inspire technical and non-technical audiences alike.MS or PhD in Computer Science, Machine Learning, Statistics, Operations Research or related field (or equivalent experience).Bonus: Open-source contributions, peer-reviewed publications, or experience in two-sided marketplace ecosystems.Salary range:San Francisco: the pay range for this role is $339,000 to $466,000 per year. This role will also be eligible for equity and benefits. Actual base pay will be determined based on permissible factors such as transferable skills, work experience, market demands, and primary work location. The base pay range provided is subject to change and may be modified in the future.Hybrid Faire employees currently go into the office 3 days per week on Tuesdays, Thursdays, and a third flex day of their choosing (Monday, Wednesday, or Friday). Additionally, hybrid in-office roles will have the flexibility to work remotely up to 4 weeks per year. Specific Workplace and Information Technology positions may require onsite attendance 5 days per week as will be indicated in the job posting. Why you’ll love working at FaireMove fast: You'll own meaningful problems that serve customers around the globe with the agency to move fast and see your results clearly.Equipped to scale: We invest in what matters, including the latest enterprise AI tools, to help you work smarter and get more out of every day.Best in class: Our team is full of sharp, kind, and generous colleagues who care about their craft and about helping you grow in yours.Real rewards. Competitive pay, equity, and comprehensive benefits designed to support your life inside and outside of work.Belonging: We're intentional about building an environment where every Faire employee has equal access to opportunities, growth, and success.Faire was founded in 2017 by a team of early product and engineering leads from Square. We’re backed by some of the top investors in retail and tech including: Y Combinator, Lightspeed Venture Partners, Forerunner Ventures, Khosla Ventures, Sequoia Capital, Founders Fund, and DST Global. We have headquarters in San Francisco and Kitchener-Waterloo, and a global employee presence across offices in Toronto, London, and New York. To learn more about Faire and our customers, you can read more on our blog.Faire provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, color, religion, sex, national origin, age, disability, genetics, sexual orientation, gender identity or gender expression.Faire is committed to providing access, equal opportunity and reasonable accommodation for individuals with disabilities in employment, its services, programs, and activities. Accommodations are available throughout the recruitment process and applicants with a disability may request to be accommodated throughout the recruitment process. We will work with all applicants to accommodate their individual accessibility needs. To request reasonable accommodation, please fill out our Accommodation Request Form (PrivacyFor information about the type of personal data Faire collects from applicants, as well as your choices regarding the data collected about you, please visit Faire’s Privacy Notice (