Senior Full Stack Engineer

Senior Full-Stack Software Engineer - Identity, Access & Platform Engineering At a Glance Senior full-stack engineer role combining TypeScript/React product work with deep authentication, authorisation and event-driven platform engineeringRemote (UK), full-time, with a genuinely flexible working cultureSalary: £65,000- £80,000Modern stack: TypeScript, Node.js/Fastify, React, AWS (Kubernetes/EKS), Kafka/SNS/SQSSmall, high-trust engineering team with real influence over architecture and technical direction About the Company Our client is a fast-growing, cloud-native technology company building a platform that sits at the heart of how its customers manage identity, access and high volumes of operational data in real time. The engineering team works in small, cross-functional squads and takes real ownership of the products they build, from architecture through to production. It is a business that invests seriously in its engineering culture, backing its people with the autonomy, tooling and support to do their best work. The Role As a Senior Full-Stack Software Engineer, you will work within a cross-functional team of engineers, product managers and designers to design and build core platform capabilities, with particular focus on authentication, authorisation and auditing. You will move comfortably across the stack, from React front ends to TypeScript and event-driven backend services, while contributing to the access-control mechanisms that other engineering teams build on top of. You will have real autonomy over how problems get solved, work directly with product and design to take ideas from concept to delivery, and help shape engineering standards as the platform scales. This role suits someone who enjoys hard distributed-systems problems as much as they enjoy shipping clean, well-tested product features. Key Responsibilities Design, build and ship full-stack features across TypeScript microservices and React applicationsDesign and evolve backend services for authentication, authorisation and audit logging at scaleBuild and extend event-driven pipelines using Kafka and AWS SNS/SQS for asynchronous processing, auditing and workflow automation, including idempotent consumers and dead-letter queuesDesign clean, maintainable APIs and contribute to architectural decisions across multiple productsIntegrate identity and access platforms such as Auth0/OIDC alongside internally built access-control mechanismsOwn services end to end, from API design and data modelling through testing, observability and production deploymentBuild secure systems incorporating JWT/OIDC authentication, fine-grained authorisation and resource-ownership validationWrite high-quality automated tests, including unit, integration and end-to-end coverage, as part of everyday developmentMentor and coach engineers through code review, technical discussion and collaborative problem solvingImprove developer experience, CI/CD pipelines and engineering standards across the team What You'll Need Essential: 5+ years of professional software engineering experience building production-grade systemsStrong TypeScript, Node.js and React experienceExperience designing, building and operating production backend services and REST APIsSolid exposure to event-driven or message-based architectures (Kafka, AWS SNS/SQS, RabbitMQ) and high-volume data processingPractical experience with CI/CD pipelines for production servicesFamiliarity with public cloud platforms, ideally AWS, including containerisation and KubernetesExperience building observability and monitoring into applicationsComfortable owning a loosely defined feature from concept through to productionExperience partnering with remote, cross-functional teams across different time zonesDesirable / Nice to Have: Experience with authentication or identity management platforms such as Auth0, Okta or KeycloakExperience in a compliance-driven or regulated environment (fintech, KYC/AML, or similar)Experience with monorepo tooling (pnpm, TurboRepo) and GitHub Actions Why Apply? Competitive salary, disclosed on applicationRemote-first working, with a genuinely flexible approach to work/life balanceUnlimited PTOMedical, dental, vision and life insurance coverSmall, high-trust engineering team with significant influence over architecture and technical directionReal ownership from design through to deployment, with very little bureaucracyThe chance to solve genuinely hard problems in distributed systems, identity and access architectureSupport for career and professional development, including conferences, seminars and continued education