DANIEL CAVALLI

Senior Machine Learning Engineer @ Nubank | MLOps, AI, ML Infrastructure

Rio de Janeiro, Rio de Janeiro, Brazil

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Summary

ML Infrastructure Engineer at Nubank, helping build and scale the company's AI platform that powers 150+ Data Scientists and Machine Learning Engineers across multiple business units. My work bridges infrastructure and applied ML, optimizing distributed training with multi-cluster, multi-GPU strategies and designing deployment workflows through Argo and Tekton. I focus on creating reliable, reusable systems that turn complex models into production-ready services. My interests lie in MLOps, Distributed Systems, and Machine Learning Infrastructure, especially where they intersect with fintech innovation and large-scale data products.

Experience

February 2026 - Present

Senior Machine Learning Engineer

Nubank · Rio de Janeiro, Brazil

Leading the next generation of Nubank's AI Platform infrastructure, serving 150+ Data Scientists and MLEs across the organization.

  • Orchestrating a full greenfield migration from a shell-script-based deployment to Infrastructure as Code using Pulumi, replacing all existing tooling and integrating Nubank's networking, OAuth, and security requirements at scale.
  • Leading the upgrade from Kubeflow 1.7 (AWS distribution) to Kubeflow 1.11 (Community Manifests) in a complete platform rebuild adopting KFP v2, enhanced network policies, and open-standard tooling with no carry-over from the previous stack.
September 2023 - February 2026

Machine Learning Engineer

Nubank · Brazil

Scaled Nubank's AI Platform to serve 150+ Data Scientists across multiple business units, supporting 200+ models in production.

  • Drove distributed GPU training optimization through multi-cluster, multi-GPU strategies, reducing large model training time from 21 days to 3 days and cutting development iteration cycles from ~25 minutes to under 2 minutes.
  • Enhanced platform reliability and reusability by improving integrations across Kubeflow, Dagster, Argo, Tekton, Clojure Services, and the in-house CPW library, revamping core components to increase developer velocity at scale.
  • Architected a geo-agnostic expansion framework for Nubank's AI Platform, enabling seamless onboarding of new countries without infrastructure rework and directly supporting the company's international growth strategy.
May 2022 - September 2023

Senior Machine Learning Engineer

PicPay · Brazil

Laid the foundation for the ML and Data Infrastructure of PicPay's High Income business unit, establishing scalable systems that bridged Data Engineering and MLOps practices.

  • Boosted team contribution rate from under 2 PRs/month to 50+ PRs/month by designing a faster, more accessible MLOps framework on AWS SageMaker that onboarded Data Scientists into the development workflow, enabling the unit's first real-time credit/lending models to reach production.
  • Built DataOps pipelines supporting 150+ datasets fully integrated with the company's DataLake, ensuring reliable and consistent data access for analytics and model training across workflows.
  • Designed end-to-end MLOps infrastructure for real-time model deployment, monitoring, and experimentation.
November 2021 - May 2022

Machine Learning Engineer

frete.com · Brazil

Developed early MLOps foundations and machine learning models to enhance the company's risk management and fraud detection systems for truck drivers and freight operations.

  • Designed ML models to expand risk management and fraud prevention tools while improving model deployment efficiency through internal MLOps solutions.
  • Evaluated and integrated external data providers to improve model performance and cost-effectiveness across analytics workflows.
September 2020 - November 2021

Machine Learning Engineer

M4U · Brazil

Built M4U's first Anti-Fraud solution and AI Platform from concept to production, establishing ML infrastructure as a core product capability within a small ML team.

  • Developed an end-to-end anti-fraud system for online payments combining a rule-based engine and an ML model, reducing fraud by ~30% and preventing ~15,000 fraudulent transactions/month at under $0.01 cost per transaction scored.
  • Built an MLOps platform using GitOps, AWS SageMaker, and Terraform that accelerated model delivery from 1 deployment/year to 1 deployment/month.
  • Advocated for and defined the Anti-Fraud platform as a key product initiative, aligning engineering and business teams around its strategic value and deployment across multiple production environments.
May 2019 - September 2020

Junior Data Scientist

M4U · Brazil

Contributed across the full ML workflow while helping shape the early data foundations that later evolved into the company's AI Platform.

  • Designed and maintained observability tooling for ML models in staging and production, enabling data and concept drift detection across the platform.
  • Delivered exploratory and descriptive analyses for 4 telecom client companies and 2 internal platform teams (Recharging and Recurrence), producing visual reports that accelerated operational diagnostics and identifying key improvements.
November 2018 - May 2019

Junior Data Scientist

Oi S.A · Rio de Janeiro Area, Brazil

Started my career within Oi's UX Research Lab, where I combined analytics, user research, and data science to improve digital experiences for millions of users of the Minha Oi platform.

  • Developed an early NLP model leveraging BERT, before the rise of LLMs, to analyze open-text feedback from user surveys, automatically extracting insights for product and design teams.
  • Conducted analytical and exploratory studies to validate hypotheses raised by the UX team regarding user behavior and engagement patterns.
  • Retrieved and structured data that served as the foundation for UX improvements and decision-making across web and mobile channels.

Skills

Kubeflow · Distributed Systems · Machine Learning Infrastructure

Education

Bachelor of Economics - BBA, Economics
Federal University of Rio de Janeiro
March 2017 - December 2023
Associate degree in Game Development and Software Engineering, Computer Software Engineering
Nucleo Avançado em Educação - NAVE
2014 - 2016

Languages

Portuguese (Native or Bilingual) · English (Full Professional)