Python Backend Engineer (Remote, Full - Time) [AS347]

About Smart Working At Smart Working, we believe your job should not only look right on paper but also feel right every day. This isn’t just another remote opportunity - it’s about finding where you truly belong, no matter where you are. From day one, you’re welcomed into a genuine community that values your growth and well-being. Our mission is simple: to break down geographic barriers and connect skilled professionals with outstanding global teams and products for full-time, long-term roles. We help you discover meaningful work with teams that invest in your success, where you’re empowered to grow personally and professionally. Join one of the highest-rated workplaces on Glassdoor and experience what it means to thrive in a truly remote-first world. About the Role As a Backend Engineer (Python), you will contribute to building an AI-native cybersecurity platform, helping customers operate and manage their own fleets of AI agents. You will develop backend systems supporting security detection, investigation and AI-assisted resolution. You will join a team of 14+ engineers across Backend, DevOps, Endpoint, Frontend and Design, reporting to the VP of Engineering and AI. The team follows a flat structure and a single-owner model, with one engineer per discipline per project. This role is suited to an autonomous, customer-focused engineer who takes end-to-end ownership, collaborates effectively and uses AI to deliver high-impact solutions. Responsibilities - Build the Agent Control Plane, enabling customers to run and manage their own fleet of AI agents. - Design, develop and deliver Python services using FastAPI and Flask for security detection, investigation and AI-assisted resolution. - Build the AI agent layer, including tool calling, Model Context Protocol (MCP) integrations and human approval mechanisms before actions are performed on live systems. - Model and query large security datasets using ClickHouse, ensuring strict tenant isolation. - Take end-to-end ownership of assigned projects, from understanding customer problems through to delivering solutions. - Engage directly with customers to understand their requirements and ensure their problems are resolved. - Independently manage priorities and deliver high-impact work while maintaining continuous communication and collaboration with the team. - Use AI agents and frontier models to learn unfamiliar technologies, navigate unfamiliar codebases and manage multiple projects. - Manage two major projects alongside smaller AI-driven tasks. Requirements - Minimum 5 years of overall software engineering experience. - Minimum 5 years of hands-on production Python development experience. - Daily, hands-on experience using AI agents and frontier AI models to build software. - Demonstrated ability to use LLMs independently to learn unfamiliar technical areas, work across unfamiliar codebases and deliver software solutions. - Experience in system design for distributed services. - Strong understanding of API design and data modelling. - High standards for software testing, correctness and observability. - Ability to take complete ownership of features and projects, from understanding customer requirements to resolving customer problems. - Strong customer focus, with a willingness to communicate directly with customers rather than simply completing assigned tickets. - Ability to identify urgent priorities, respond quickly and focus on delivering work with the greatest impact. - Ability to work autonomously, set priorities and make decisions without constant supervision while maintaining effective communication and collaboration. - A growth mindset, with openness to constructive criticism, willingness to discard or rework code and projects when necessary, and commitment to improving the wider team. - A trustworthy and accountable approach, demonstrating honesty, attention to detail, early communication of problems and consistent delivery. - Ability to work effectively with colleagues rather than in isolation. - Ability to clearly explain technical decisions, implementation approaches and solutions. - Willingness to own projects end to end. - Availability to work remotely during UK working hours. - Ability to join as soon as possible. Nice to Have - Experience with FastAPI or Flask. - Experience with ClickHouse or other columnar analytics databases. - Production experience with agent harnesses, LLM tool use, Model Context Protocol (MCP) or Retrieval-Augmented Generation (RAG). - Experience developing or maintaining multi-tenant SaaS platforms. - Experience in cybersecurity, detection engineering or large-scale event processing. - Some experience with C++ or TypeScript.