Software Engineer (Backend)

This is a hybrid role that requires 3 days/week in our London office

About Lorum

The structural conflict at the centre of correspondent banking is not technological. It is economic. Banks earn revenue from their balance sheets: they lend deposits, capture FX spreads, and hold funds as long as it is rational to do so. Clearing, the act of releasing funds quickly and predictably, competes directly with those economics. An institution designed to lend has a structural incentive to hold deposits; an institution designed to clear has an incentive to release them. When one institution does both, clearing loses. The result is unpredictable settlement, trapped capital, and a correspondent network shrinking by design.

Why Lorum

Lorum was founded on a different premise: clearing as the business, not a byproduct. The model has been operational since 2023 and grew 55x in 2025, with USD clearing now the majority of volumes alongside a growing treasury offering. We have applied for a U.S. national trust bank charter. The people we hire now will build the clearing and treasury infrastructure it unlocks.

The role

We're looking for Backend Software Engineers to join our engineering team in London. You'll build the systems that move money for banks: the services, ledgers and integrations behind Lorum's clearing and treasury products, mostly in Rust. Correctness matters more than cleverness here. A payment that settles twice, or not at all, is a real problem for a real bank. You'll join a small, cross-functional team, own services end to end from design through production support, and work closely with Product, Operations and Security & GRC as we scale volumes and prepare for a regulated trust bank environment.

Day-to-day 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, designed 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 help raise the technical bar

Success in the first 3 to 12 months

• Ship production changes to a core clearing or treasury service, and join the on-call rotation for it, within 3 months

• Own the design and delivery of a meaningful feature or integration end to end by month 6

• Measurably improve the reliability, throughput or reconciliation accuracy of a service you own by month 12

• Help raise engineering standards across the team through code review, testing and documentation

Ideal Candidate

Must Haves

• 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. We don't expect you to know our exact stack

• 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

• A strong testing mindset and familiarity with CI/CD

• Able to work hybrid, 3 days/week in the London office

Nice to haves

• Rust in production, or substantial personal/OSS Rust projects

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

• 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

How we work (attitudes & behaviours)

• Correctness first: you'd rather ask one more question than ship an ambiguous money flow

• Owns problems end to end, from design to production support, not just executing tickets

• Clear written communication; documents decisions and trade-offs

• Comfortable with the pace and ambiguity of a fast-growing clearing and treasury infrastructure business

• Low ego, high standards; gives and takes direct feedback well

Benefits

• Flexible vacation policy

• Private Healthcare

• Employee stock ownership (ESOP)

• Flexible working and autonomy

• Pay it forward days - we offer 2 annual pay it forward days where you can take time to volunteer for a charitable cause that is important to you.

• Wellness days - we believe you can only work your best when you feel your best, and we know working at Lorum is intense, so we offer 3 wellness days every quarter where you can take time to re-energize

Equal opportunity: Lorum is an equal opportunity employer. We welcome applications from all qualified candidates regardless of race, colour, religion, sex, national origin, age, disability, sexual orientation, gender identity, or any other protected characteristic.