Senior Software Engineer

Senior Software Engineer Role in Cyber Security SaaS Platform - Full Stack Location: Remote (UK-based), with occasional in-person attendance required for company events · Type: Full-time · Reports to: Technical Lead About the Role We're a small, fast-moving engineering team building a cyber security SaaS platform that gives customers device scanning, vulnerability patching, cyber risk assessments, and incident reporting - all in one place. We're looking for a Senior Software Engineer to join as an individual contributor and work across the full stack, from day one. We're an AI-native engineering team. We expect you to use AI as a genuine part of how you design, build, test, and review software, and, just as importantly, to know when human judgment, input, and validation are essential. In a cyber security product, that judgment matters more than anywhere else. This is a remote-first role. You will, however, be expected to attend occasional in-person events, such as hackathons, conferences, quarterly planning sessions and team get-togethers. These are a genuine part of how we build the team, not a box-ticking exercise, so a willingness to travel a few times a year matters. This is not a role for someone who needs a lot of structure or supervision. We're a small, supportive team, but we don't have the bandwidth for extended hand-holding beyond a 4-week induction period. We need someone who can quickly understand our systems, ask the right questions early, and then get on with delivering - independently, and to a high standard. What You'll Do Design, build, and ship features across our full stack - from the React/GraphQL frontend to the Django/Python backend.Work directly with product and design to turn ambiguous requirements into working software.Own features end-to-end: design, implementation, testing, deployment, and monitoring in production.Contribute to architecture and technical decisions as a senior voice on a small team - your input matters here.Integrate with third-party security and infrastructure providers via REST APIs.Maintain and improve async processing pipelines (Celery, Redis, RabbitMQ) that power scanning and reporting workloads.Help evolve our authentication/authorization layer (JWT, SSO) as we scale.Write clean, well-tested, maintainable code, and review others' code with the same bar.Use AI throughout your engineering workflow, from exploring problems and generating code to reviewing, building and testing solutions, while bringing a critical eye to AI-generated output and taking full responsibility for everything you ship.Contribute to and refine the AI agents, harnesses and automated workflows that improve how the team delivers.Help define where AI accelerates our work and where human review is non-negotiable, particularly for security-sensitive code, authentication and data handling.Assist with production support as needed.What We're Looking For Technical experience: 5+ years of professional software engineering experience, with genuine full-stack range.Frontend: React, Node.js, GraphQL (ideally Apollo), and comfort with WebSockets/real-time data.Backend: Python (Django preferred), PostgreSQL, and GraphQL API design (Graphene or similar).Experience with async task queues (Celery + Redis/RabbitMQ or equivalent).Solid understanding of REST API design and integration with third-party services.Experience with JWT-based auth and SSO (OAuth2/SAML/OIDC).Familiarity with containerized deployments on AWS (ECS or similar) and general AWS literacy.Comfortable working with CI/CD pipelines and infrastructure-as-code concepts. AI-native engineering practice: Demonstrable experience using AI as a core part of your day-to-day engineering workflow, not just as a code completion tool. You can speak concretely about how AI has changed the way you work.Hands-on experience working with AI agents, harnesses or agentic workflows, with a clear understanding of what they can and cannot do reliably.Sound judgement about when a task can be delegated to AI and when human input and validation are of the utmost importance. You treat that judgement as a core engineering skill.You work with AI-generated output critically: you verify it, refine it, test it and own what ships. Working style (equally important): Demonstrated ability to work independently- you can pick up a loosely defined problem, scope it, and drive it to completion without close supervision.Strong communicator who proactively flags blockers, risks, and decisions rather than waiting to be asked.Comfortable operating with ambiguity in a small team where process is lightweight and priorities can shift.A pragmatic, ownership-driven mindset - you care about the outcome, not just your ticket.You hold AI-assisted work to the same standard as anything else you produce: no shipping unverified output, ever.Prior experience in a startup, scale-up, or small-team environment is a strong plus. Nice to have: Background in cyber security, vulnerability management, or compliance/risk tooling.Experience with security scanning tools, patch management systems, or SIEM/reporting platforms.Exposure to multi-tenant SaaS architecture.Experience building AI agents, harnesses or automated workflows in a production context.Awareness of AI-specific security risks, such as prompt injection, data leakage into models and supply chain risks in AI tooling. What You'll Get A meaningful, high-ownership role on a small team where your work directly shapes the product.Direct exposure to the full architecture - no silos, no red tape.A supportive team culture, with structured onboarding to set you up for independent success.Access to frontier AI tooling and a genuine mandate to shape how the team uses it.Remote-first working, with travel and expenses covered for in-person events like hackathons, conferences and quarterly planning.