Traditionally, ML systems were built to solve narrow tasks (e.g., item recommendations), with orchestration logic hard-coded outside the model. Increasingly, LLMs are becoming the orchestration layer, deciding which models to invoke, when to use them, how to interpret outputs, and how to chain steps together. In this paradigm, the models we build deliver low-latency, large-scale personalization that advances Block’s mission of economic empowerment. We work closely with Design, Product, and Engineering teams across Block’s ecosystem, applying a spectrum of approaches from simple heuristics and embeddings to deep learning and large language models. We also invest heavily in agentic engineering and AI-assisted tooling to enable high-velocity, reliable development. This includes code generation, automated testing, documentation, and developer workflows. You will play a key role in shaping how these practices apply to ML with techniques like AutoResearch.

Lead strategic initiatives in AI Personalization, driving the vision, architecture, and execution

Develop and deploy new AI/ML models that power search & recommendations in traditional UX as well as new agentic interfaces

Deploy to production at scale to personalize every user’s experience

Be a technical leader and establish quality practices that stick, make broader design decisions and set an example for others to follow

Collaborate with a cross functional team of designers, business partners, and software engineers to build new technologies and features

Design experiments, test them on production users, analyze and repeat