At Nubank, building technology for financial services goes far beyond simply creating robust systems. Here, every technical decision aims to support millions of customers with security, efficiency, and constant innovation. 

In this article, we’ll reveal some of the behind-the-scenes of our engineering, highlighting how we approach continuous delivery, immutability, standardization, cloud computing, intelligent data use, rigorous security, and artificial intelligence.

Continuous delivery: speed with confidence

Our engineering enables frequent and safe releases of new features. We heavily invest in automated testing practices to ensure each change is validated before reaching users. 

We use techniques such as canary deployments, controlled rollouts, and feature flags, allowing incremental and reversible changes. 

This approach enables quick adaptation to market demands and significantly reduces production errors.

Check our job opportunities

Simplifying complexity

One of Nubank’s technical approaches is immutability. We use tools that minimize state changes, such as the immutable database Datomic, Kafka for asynchronous communication, and functional programming with Clojure. 

This drastically reduces system complexity, making maintenance easier and simplifying the identification and correction of problems, as well as improving service consistency and predictability.

Scaling together

At Nubank, standardization is considered a strategic advantage that accelerates development and fosters collaboration. By setting clear standards for languages, frameworks, databases, and processes, we reduce cognitive load on our teams. 

This allows our engineers to focus on solving complex challenges while continuously sharing and improving technical best practices.

Cloud-first: agility at scale

From the beginning, we’ve adopted a cloud-first approach, leveraging infrastructure provided by specialized partners. This strategy allows us to scale quickly, focusing on developing features that directly add value for our customers without managing infrastructure complexity. 

Although specific cases require on-premises solutions due to technical or regulatory needs, the predominant use of cloud ensures essential flexibility and scalability for rapid growth.

Democratizing access to data

At Nubank, data is crucial for strategic and operational decision-making. Our ETL infrastructure processes around 7 terabytes daily, providing internal teams with secure and rigorously controlled access to information. 

We have evolved to a Data Mesh model, segmenting datasets into domains with standardized interfaces. This approach promotes autonomy, simplifies data access, and accelerates the development of data-driven solutions.

Security and privacy come first

Security and privacy are top priorities at Nubank. Customer trust directly depends on our ability to protect information and maintain system stability. We employ advanced authentication techniques, rigorous access controls, continuous monitoring, and chaos engineering to anticipate and mitigate failures. 

This ensures high service availability, protection against threats, and compliance with strict financial sector regulations.

Artificial intelligence and responsible innovation

We apply artificial intelligence strategically in areas such as fraud detection, enhancing security, and continually improving customer experience. Additionally, we actively explore generative AI and assistants like Devin to optimize internal processes and increase technical productivity. We view AI as a powerful tool that, when applied responsibly and strategically, generates significant positive impacts both internally and externally.

These practices and approaches evolve as Nubank grows and faces new challenges. We remain committed to building technology that consistently delivers security, efficiency, and innovation for our customers.

If you want to know more about the technical backstage and real stories of Nubank’s engineering, check out the episode of the Hipster Ponto Tech podcast, with the participation of the CTO at Nubank, Vitor Olivier.

Check our job opportunities