Backend Software Engineer (Rust, Hybrid)

About the role

Lorum is a clearing and treasury infrastructure company founded in 2023, which has grown 55x in 2025 and is applying for a U.S. national trust bank charter. It is hiring Backend Software Engineers in London to build the services, ledgers and integrations behind its USD clearing and treasury products, mostly in Rust. The role is hybrid, with 3 days per week in the London office.

Key responsibilities

• Design, build and maintain backend services and APIs in Rust (or a similar strongly typed language, with a path to Rust)
• Implement robust domain logic for clearing, payments, accounts and reconciliation
• Build systems for high-volume, high-reliability financial workloads, with metrics, logs and tracing from day one
• Take part in on-call and incident response for the services you own
• Work with Security and GRC so services meet requirements such as SOC 2 and ISO 27001
• Partner with Product to scope work, review code, write thorough tests and raise the technical bar

Required profile

• 3+ years building backend systems in a strongly typed language (e.g. Rust, Go, Java, Kotlin, C++)
• Commercial experience with distributed services or APIs
• A real interest in working in Rust day to day, shown through prior Rust work or demonstrable learning
• Solid backend fundamentals: concurrency, data modelling, transactions, reliability and observability
• Experience designing and consuming APIs (REST/gRPC/GraphQL) and integrating with services and data stores
• Strong testing mindset and familiarity with CI/CD
• Able to work hybrid, 3 days per week in the London office

Nice to have

• Rust in production, or substantial personal or open-source Rust projects
• Fintech, payments, banking, trading or other financial infrastructure experience
• Event-driven architectures, message queues and stream processing
• PostgreSQL (or similar) and data-intensive workloads
• AWS/GCP, Docker and Kubernetes
• Regulated or high-assurance environments

What we offer

• Flexible vacation policy
• Private healthcare
• Employee stock ownership (ESOP)
• Flexible working and autonomy
• Two annual "pay it forward" days to volunteer for a charity
• Three wellness days every quarter