Principal Engineer

ABOUT UNIT Money is fundamental to how people and businesses operate, but it often sits outside the software they use every day. Unit changes that. Unit is a financial infrastructure platform that enables technology companies to store, move, spend, and lend money inside their product. Unit processes over $100B in annual transaction volume, serves 2M+ accounts, and handles 11M+ API calls daily for category-defining companies including Wix, Highbeam, Wayflyer and Relay. Today, leading technology companies use Unit to create smarter money experiences, deepen customer relationships, and unlock new revenue. We’re building the infrastructure that will make financial products a native part of software, and we’re looking for people who want to help shape what comes next. We’ve raised $160m+ from top investors including Insight Partners and Accel, and 60+ angels. We are proud to be recognized on CNBC World's Top Fintech Companies. https://www.cnbc.com/worlds-top-fintech-companies-2026/ THE ROLE As a Principal Engineer at Unit’s CTO Office, you will help shape the long-term technical direction of our engineering organization. This role is centered around broad, cross-engineering technical challenges, with a focus on areas such as reliability, performance, architecture, cost effectiveness, developer experience, and security. You will work closely with engineering teams across the organization on key initiatives that improve how we build, operate, and scale our systems. This includes leading technical efforts, identifying opportunities for engineering improvements, and helping ensure that as our product evolves, our technology continues to develop in a healthy and scalable manner. You will operate within a large-scale distributed microservices environment, helping solve complex challenges that often span multiple domains. We see this role as ideal for someone looking to influence the foundations of our industry-defining platform. KEY RESPONSIBILITIES - Partner with engineering teams on technical efforts and lead cross-team engineering initiatives. - Contribute hands-on to critical technical efforts, investigations, and infrastructure initiatives across the organization. - Lead initiatives that improve the reliability, performance, cost effectiveness, developer experience, security, and operational health of Unit’s systems. - Identify long-term technical opportunities and challenges, and drive engineering improvements that raise the overall quality and effectiveness of our platform. - Design and implement solutions for challenges at the core of Unit’s platform. - Support the continued evolution of Unit’s engineering practices. WHAT WE'RE LOOKING FOR? - 10+ years of proven experience designing, building, deploying, and operating large-scale distributed systems in a microservices environment. Previous experience in a Principal Engineer role at a large-scale SaaS company is an advantage. - Strong understanding of production systems concepts such as reliability, scalability, performance, observability, cost efficiency, and security. - Strong systems-thinking skills and sound engineering judgment when solving complex technical challenges. - Excellent collaboration and communication skills, with the ability and desire to work with people across teams and disciplines. - Experience with cloud-based infrastructure. Strong familiarity with AWS and Kubernetes is a plus. - Passion for building high-quality software. Experience with Scala and Functional Programming ecosystems (e.g. ZIO, Cats, Scalaz) is an advantage. - Genuine interest in the product and business domains we operate in, and in connecting technical decisions to customer and business outcomes. - Experience with modern software architecture and design patterns, including event-driven architectures, Event Sourcing, CQRS, and Domain-Driven Design (DDD), is an advantage. - Experience with workflow orchestration or durable execution frameworks (e.g. Temporal, Cadence, AWS Step Functions) is an advantage. LIFE AT UNIT Working at Unit means helping shape the future of financial technology. We’re a global team that thinks big, moves with purpose, and takes ownership of the work we do. We care deeply about building great products, solving hard problems, and helping our customers succeed. We value people who are curious, collaborative, and ready to make an impact. At Unit, you’ll have the opportunity to do meaningful work, learn alongside talented teammates, and help build what’s next.