Software Engineer (backend)

Location: London or New York - in office 4 days a week

About Job

We are looking for an experienced backend engineer to join our team and help build the foundational infrastructure. You’ll be joining a small, cross-functional team focused on shipping real value quickly and building systems that are observable, reliable, and designed to evolve.

This role is ideal for someone who enjoys working in fast-moving environments, thrives in ambiguity, and cares deeply about building high-quality backend systems that solve real-world problems. We’re particularly looking for engineers with strong experience in distributed systems and an interest in working with Rust.

We don’t expect you to have experience with our exact stack, but we do expect you to bring deep engineering expertise, sound judgment, and a pragmatic approach to problem solving.

Skills & Qualification

Must-Haves 

• 3+ years of experience building backend systems in a strongly typed language (e.g. Rust, Go, Java, Kotlin, C++, or similar). 

• Commercial experience in backend or systems engineering, working on distributed services or APIs. 

• Genuine interest in working with Rust day‑to‑day (prior Rust experience or demonstrable learning is important). 

• Solid understanding of backend fundamentals: concurrency, data modelling, transactions, reliability, and observability. 

• Experience designing and consuming APIs (REST/gRPC/GraphQL) and integrating with other services and data stores. 

• Strong testing mindset and familiarity with CI/CD workflows. 

• Clear communication skills and a collaborative approach to working with Product, Operations, and other engineers.

  Nice-to-Haves 

• Hands‑on experience with Rust in production or substantial personal/OSS projects. 

• Experience in fintech, payments, banking, trading, or other financial infrastructure domains. 

• Familiarity with event‑driven architectures, message queues, and stream processing. 

• Experience with PostgreSQL (or similar relational databases) and data‑intensive workloads. 

• Experience running services on a major cloud provider (e.g. AWS, GCP) and with containerisation/orchestration (e.g. Docker, Kubernetes). 

• Exposure to regulated or high‑assurance environments and the constraints they introduce.

Responsibilities

• Backend systems design & implementation 

  • Design, build, and maintain backend services and APIs in Rust (or similar languages with a path to Rust). 

  • Implement robust domain logic for clearing, payments, accounts, and reconciliation. 

  • Contribute to architectural decisions and help evolve our service boundaries and integrations.

• Scalability, performance & reliability 

  • Build systems that can handle high‑volume, high‑reliability financial workloads. 

  • Design with observability in mind (metrics, logs, tracing) and use data to drive improvements. 

  • Participate in on‑call and incident response, helping to diagnose and resolve production issues.

• Security & compliance aware engineering 

  • Work closely with Security and GRC teams to ensure services meet security and compliance requirements (e.g. SOC 2, ISO 27001). 

  • Implement secure coding practices, strong authentication and authorization patterns, and data protection controls. 

  • Contribute to internal documentation and standards around secure and compliant engineering.

• Collaboration & delivery 

  • Partner with Product Managers and other stakeholders to refine requirements and scope work. 

  • Break down projects into well‑defined tasks and deliver value iteratively. 

  • Review code, provide feedback, and help maintain high engineering standards across the team.

• Tooling, testing & continuous improvement 

  • Write comprehensive tests (unit, integration, and where appropriate property‑based tests) and support automated testing in CI/CD. 

  • Contribute to internal tooling, developer experience, and shared libraries. 

  • Share knowledge, mentor peers, and help raise the overall technical bar.