Lead Machine Learning Engineer / Applied AI Scientist

h3 About Us /h3 p Nu was born in 2013 with the mission to fight complexity to empower people in their daily lives by reinventing financial services. We are one of the world’s largest digital banking platforms, serving millions of customers across Brazil, Mexico, and Colombia. /p h3 About the role /h3 p At AI Core, we are scaling the impact of our AI initiatives to become the primary driver of Nubank’s most critical decision systems. We are seeking an strong Lead Machine Learning Engineer (Applied AI Scientist) /strong nbsp;to lead high-impact research projects that bridge the gap between state-of-the-art AI and production-grade financial systems. You will be responsible for solving complex, ambiguous problems using Deep Learning and Foundation Models, ensuring our architectures are scalable, efficient, and driving measurable business results. /p p As an Applied AI Scientist (MLE), you’re expected to: /p ol li Research Execution amp; Technical Leadership (Complexity amp; Autonomy) /li /ol ul li strong Lead and execute complex applied research initiatives /strong independently, focusing on building and optimizing architectures (e.g., Transformers, GNNs) that can be deployed across critical use cases like Credit, RecSys, GenAI, and real-time inference. /li li strong Address difficult and ambiguous modeling problems /strong that require coordination across various stakeholders (Data, Infra, Product), delivering innovative solutions with a clear focus on medium-term impact. /li li strong Bridge the gap between research and production /strong by designing architectures that respect MLOps constraints, ensuring models are optimized for latency, interpretability, and cost-efficiency. /li /ul ol li Strategic Impact amp; Collaboration (Impact) /li /ol ul li strong Develop and deliver innovative solutions /strong that address project-level challenges, focusing on pushing the latest platform and AI research improvements into downstream production models. /li li strong Actively participate in cross-functional collaborations /strong , ensuring that research outputs are seamlessly integrated into Nubank's decision-making engines. /li li strong Establish technical standards /strong within the AI Core team for experimentation, model evaluation, and code quality, inspiring peers to raise their performance. /li /ul ol li Mentorship amp; Function Contribution (Function Contribution) /li /ol ul li strong Serve as a technical mentor /strong for senior engineers and researchers, providing guidance on deep learning fundamentals, problem formulation, and research methodology. /li li strong Actively contribute to the function's growth /strong by participating in mandatory activities like hiring (interview panels) and leading internal task forces to improve our ML lifecycle. /li li strong Contribute to thought leadership /strong by participating in research collaborations or internal papers that align with Nubank’s strategic goals. /li /ul h4 strong What are we looking for? /strong /h4 ul li strong Professional Experience: /strong 5-7+ years in applied AI/ML, with a proven track record of delivering research-driven systems into production environments /li li strong Technical Mastery: /strong ul li Deep expertise in nbsp; strong Deep Learning architectures /strong (Transformers, Multimodal, or GNNs). /li li Strong coding skills in strong Python /strong and proficiency with frameworks like strong PyTorch, JAX, or TensorFlow /strong . /li li Solid understanding of strong MLOps /strong and the constraints of deploying models at scale. /li /ul /li li strong Problem Solving: /strong Sophisticated skills in ML problem formulation and the ability to navigate uncertainty when data is messy or unavailable. /li li strong Communication: /strong Ability to communicate complex technical concepts to both technical peers and cross-functional stakeholders, ensuring alignment and buy-in. /li li strong Analytical Capacity: /strong Experience with large-scale experi