Senior Backend Payments Engineer in London

Plasma is building money that just works. Plasma One is our flagship product: a stablecoin neobank where people send and receive money in seconds globally, earn yield every day, and spend with a Visa card in over 150+ countries. Now live in private beta with 100,000+ people on the waitlist. Under the hood sits the Plasma network, a blockchain we designed from first principles for stablecoin payments. Stablecoins will reshape global finance. We're building the full stack that gets them there, from the underlying infrastructure to the app in your pocket. We are redefining how money moves.

Team Culture

At Plasma, you join a team that is rewriting how the world interacts with money. We hire people who are relentless about their craft and expect that same standard from everyone around them. This is where you will do the hardest and most meaningful work of your career. We work with trust, clarity, and ambition. Everyone owns their craft, moves with urgency, and contributes beyond their lane. We back each other, we debate hard, and we hold a high bar for what great looks like. Plasma is built for people who thrive on challenge and want to leave a mark.

The Backend Payments Team

Payments are the backbone of Plasma One. This team builds the systems that move money safely, predictably, and at scale, across blockchains, banking rails, and internal ledgers. As a Senior Backend Payments Engineer, you will operate at the system level. You’ll help define how our payments architecture works end-to-end, from transaction lifecycle and reconciliation to failure handling, observability, and scale. This is not a narrow execution role. You will shape architecture, influence standards, and raise the technical bar across the team. We build our backend primarily in TypeScript. You should love writing clean, high-quality TypeScript and care deeply about correctness, reliability, and maintainability.

What you will do

• Build and own critical backend systems in TypeScript that power payments, balances, settlement, and reconciliation.
• Design reliable money movement flows with strong guarantees around idempotency, consistency, and failure recovery.
• Lead technical architecture across the payments domain, including system boundaries, data models, and operational strategy.
• Work closely with product, compliance, and infrastructure to ship financial primitives that hold up under real-world use and real-world scrutiny.
• Define how we handle edge cases: partial failures, retries, timeouts, chargebacks, reversals, and reconciliation gaps.
• Raise the bar on engineering quality: code standards, testing strategy, monitoring, and incident response.
• Mentor engineers and drive technical clarity across the team, especially in complex or ambiguous areas.
• Help make stablecoin payments feel boring in the best possible way: fast, predictable, and trustworthy.

Who you are

• A senior, hands-on backend engineer with a track record of shipping and owning production systems.
• Deep experience building backend services in TypeScript (Node.js) and strong engineering instincts around reliability and correctness.
• Comfortable taking systems from zero to one, and then scaling them without losing clarity.
• Strong judgment around tradeoffs: speed vs safety, abstraction vs control, simplicity vs flexibility.
• You think in systems: APIs, state machines, data integrity, observability, and operational risk.
• You communicate clearly, write clean code, and can lead through technical decisions.
• You have solid experience building payments, ledgering, or financial infrastructure.

Nice to have

• Fintech, banking, or crypto-native background.
• Experience designing event-driven systems (queues, workflows, asynchronous processing).
• Familiarity with stablecoins, custody, settlement, and blockchain transaction lifecycles.
• Experience working close to launch and still shipping smoothly.

Salary and Benefits

At Plasma, we provide each team member with the tools they need to succeed. Benefits for full-time employees include:

• Above market salary plus token compensation.
• Premium health insurance for you and your family fully covered by Plasma.
• Monthly wellness budget, whether for the gym, therapy, sauna & massage.
• A beautiful London HQ with gym access and daily food, for those who thrive in an office environment.
• All the tools and tech you need to operate at your best.
• Visa sponsorship and relocation support if you are joining the London office from abroad.

Data Protection & Privacy

We are committed to protecting the privacy and security of your personal data. Any personal information you provide during the recruitment process will be processed in accordance with the General Data Protection Regulation (GDPR) and applicable local data protection laws.