Principal software engineer

Salary: £100,000 - 120,000 per year Requirements: We are looking for a degree-educated Principal Software Engineer with strong backend engineering expertise. We want experience in Node.js with JavaScript and TypeScript, .NET with C#, or Java. We prefer experience with AWS, with Azure and GCP also welcome. We need strong knowledge of relational databases, ideally MySQL. We value experience designing APIs and distributed systems. We require proven experience designing and scaling complex distributed systems. We are looking for strong architectural leadership experience. We want experience mentoring or leading senior engineers and teams. We need the ability to influence technical direction across multiple workstreams. We prefer experience in high-scale or regulated environments. We value interest in agentic engineering workflows and AI-assisted development. Nice to have: experience with AWS Lambda, Fargate, SQS, SNS, DynamoDB, and cloud-native architectures. Nice to have: client-facing experience. Nice to have: experience in fintech, banking, or enterprise SaaS. Responsibilities: We will have you shape the architecture, engineering standards, and technical direction across our platform. We will have you work directly on customer problems and own solutions end-to-end. We expect you to take ownership from concept and design through development, release, monitoring, and operational support. We will have you integrate with payment platforms, banking infrastructure, FX and crypto providers, and card processors. We will have you drive architectural decisions across distributed systems and cloud infrastructure. We will have you lead technical design reviews and influence engineering best practices. We will have you mentor engineers and help scale a high-performing engineering culture. We will have you design and optimise SQL and NoSQL data models. We will have you develop APIs, asynchronous workflows, and event-streaming pipelines. We will have you deploy secure, high-availability services across AWS, GCP, and Azure. We expect you to contribute to technical strategy, architecture governance, and engineering direction. We will have you collaborate on architecture, design discussions, and domain modelling. We will have you solve complex technical and domain challenges rather than repetitive boilerplate development. We will have you support production systems through monitoring and operational ownership. Technologies: AI AWS Lambda Azure Backend C# Claude Code Cloud GCP Support Java JavaScript MySQL NoSQL SQL TypeScript ASP.NET NodeJS DevOps More: We are a fast-growing Banking SaaS provider building next-generation core banking technology and a modern, scalable core banking platform. Our engineering culture is collaborative, high trust, and low bureaucracy, with a strong focus on respect, accountability, and technical autonomy. We work in a remote-first model but are UK-based for essential company events, with quarterly travel to London for team meetings and two annual companywide offsite meetings. We support a modern engineering environment that includes agentic coding and AI-assisted development workflows, including Claude Code, to accelerate productivity. We offer a competitive salary of £100,000 to £120,000 based on experience, plus benefits including 25 days holiday plus bank holidays, family health insurance, life insurance, EMI share options, and regular social events. last updated 25 week of 2026