Principal AI/ML Research Engineer

Company Overview WEX is an innovative global commerce platform and payments technology company looking to forge the way in a rapidly changing environment, to simplify the business of doing business for customers, freeing them to spend more time, with less worry, on the things they love and care about. We are journeying to build a consistent world-class user experience across our products and services and leverage customer-focused innovations across all our strategic initiatives, including big data, AI, and Risk. Position Summary As a Principal AI/ML Research Engineer, this technical leader will drive applied AI research, novel model development, and algorithmic innovation across generative AI (GenAI), deep learning, and traditional machine learning. This technologist will lead the discovery, design, and prototyping of state-of-the-art architectures to solve complex, high-scale commerce and fintech challenges. For example, this work may include pioneering Transformer-based Payment Foundation Models (PFMs)—adapting self-attention mechanisms to large-scale tabular transaction data, user behavioral sequences, and multi-modal financial streams to produce universal embeddings that power a wide array of downstream commerce applications. This role bridges state-of-the-art academic/industry research with real-world production impact. You will closely partner with leaders in Data Engineering, Product, Security, Risk & Compliance, and Line of Business (LOB) technical teams to identify high-value opportunities, benchmark novel architectures (e.g., Tabular Transformers, LLMs, RAG, Reinforcement Learning), and transition experimental models into viable production pipelines. This Principal AI/ML Research Engineer will hold technical ownership of WEX’s AI research strategy, model optimization, algorithmic rigor, and AI experimentation standards. The vision behind WEX’s AI research is to transform multi-modal commerce and payment data into intelligent, predictive models that drive c