Staff Software Engineer Software engineering London

Checkout Ltd; Greater London; Hybrid; GBP 120,000 - 150,000; Full time

Job summary

Checkout.com, founded in London, seeks a Staff Engineer to set the technical direction for payments-scale systems. You will own architecture for high-throughput distributed services, shaping data models and integration patterns to scale with demand.

You will lead critical decisions end-to-end, drive operational excellence through observability and capacity planning, and ensure resilience and availability across the stack. This is a senior role for engineers who thrive at scale.

Responsibilities

• Own the architecture of high-throughput, low-latency distributed systems, defining the service boundaries, data models and integration patterns that let them scale by an order of magnitude
• Design for resilience from first principles - redundancy, graceful degradation, backpressure, idempotency and recovery - so that partial failures never become customer-facing outages
• Set and defend the non-functional requirements that matter: availability targets, latency percentiles, throughput ceilings, data durability and recovery objectives
• Lead the hardest technical decisions end to end, from problem framing and design review through to production rollout, migration and decommissioning of what came before
• Drive operational excellence by improving observability, alerting, capacity planning, load and chaos testing

Job description

Company Description

We’re Checkout.com. You might not know our name, but companies like eBay, Spotify, Klarna, Uber, and Sony do, because we’re behind many of the digital experiences you use every day.

We are where the world checks out, enabling over 10 billion transactions yearly for more than one billion global shoppers.

Whether you want to book a holiday, order food, renew a subscription, or check out online, there’s a good chance our tech powers the payments behind the scenes. Our platform helps the most ambitious businesses deliver effortless digital experiences, at scale.

If you want to do career-defining work, you’ve come to the right place. We move fast, think globally, and believe great teams are built by hiring exceptional people with conviction, curiosity, and the desire to make an impact.

With 20 offices across six continents and London as our HQ, we’re shaping the future of fintech – and we’re just getting started.

As a Staff Engineer at Checkout.com, you will set the technical direction for systems that process payments at very high throughput, where correctness matters on every single transaction and has significant impact. This is a role for engineers who are energised by scale and by the hard trade-offs that come with it: latency budgets, failure domains, consistency guarantees, and the operational reality of running critical infrastructure around the clock. You will operate as a force multiplier across multiple teams ‑ shaping architecture, raising the engineering bar, and turning ambiguous, business‑critical problems into designs that can be delivered incrementally. We're looking for individuals with deep technical judgement, strong ownership, and a pragmatic approach to breaking big problems into smaller iterations that deliver value continuously.

How you'll make an impact

• Own the architecture of high-throughput, low-latency distributed systems, defining the service boundaries, data models and integration patterns that let them scale by an order of magnitude
• Design for resilience from first principles - redundancy, graceful degradation, backpressure, idempotency and recovery - so that partial failures never become customer-facing outages
• Set and defend the non-functional requirements that matter: availability targets, latency percentiles, throughput ceilings, data durability and recovery objectives
• Lead the hardest technical decisions end to end, from problem framing and design review through to production rollout, migration and decommissioning of what came before
• Drive operational excellence by improving observability, alerting, capacity planning, load and chaos testing