Principal Backend Engineer

About the role Heron processes millions of sensitive financial documents for some of the fastest-growing MCA Funders, Brokers, Insurers, and Fintechs in the US and UK. We're at a point where the volume, velocity, and complexity of the data flowing through our systems and is outgrowing the way they were originally built. We need someone who's done this before: taken a platform that works and made it scale. The Challenge We've built a document automation and workflow orchestration platform that lenders, funders and fintechs rely on to make real decisions. It's working, customers love it, and we're onboarding new ones faster than ever. The challenge is that our backend was built for speed-to-market, and now we need to make it built for scale. Concretely, that means: Abstractions that let us move fast: The backend systems and patterns that let a 15-person engineering team ship product confidently without breaking things for existing customers. Multi-tenancy at scale: Dozens of enterprise customers sharing the same cloud infrastructure, each with different data sensitivity requirements, SLAs, and integration patterns. Data volume and velocity: High-throughput processing of financial documents (bank statements, tax returns, pay stubs) with ML pipelines that need to be fast, accurate, and reliable. Security and compliance: Sensitive financial data handled to exacting standards. We’re excited about this challenge because it is the kind of problem that shows up when things are going well! We're hiring this role because we couldn’t be more confident in our trajectory but need to build the foundations for the next 10x. What You'll Own This is a hands-on, high-autonomy IC role. You'll work directly with our CTO (Dom) and Head of Engineering (Oli), and you'll have real ownership over the systems that matter most. In your first few months, you'll likely: Assess our current backend architecture and identify the highest-leverage areas for improvement around reliability, scalability, and security. Partner with the p