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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Principal Software Engineer - **Company:** Lantum - **Location:** London, UK (Remote available) - **Salary:** £67,543.0 - **Contract:** Temporary contract - **Skills:** LangGraph Framework, Java (Programming Language), JavaScript (Programming Language), .NET Framework, Application Programming Interfaces (APIs), Artificial Intelligence, Amazon Web Services, Microsoft Azure, C Sharp (Programming Language), Cyber Security, Databases, Linux, DevOps, Django Web Framework, Java Virtual Machine (JVM), Python (Programming Language), PostgreSQL, Machine Learning, Microsoft SQL Server, MongoDB, Node.Js, NoSQL, Systems Development Life Cycle, OpenAI, Zero Trust Network Access, DataOps, Service-Oriented Architecture, Software Engineering, Software Factory, SQL Databases, Data Streaming, TypeScript, Web Application Frameworks, Policy as Code, LangChain, ReactJS, Blazor, Large Language Models, Multi-Agent Systems, AI Coding Agents, Backend, Agentic-AI, Containerization, Data Analytics, PydanticAI Framework, Graphql, Machine Learning Operations, React Native, Front End Software Development, Hardware Infrastructure, Google Gemini, Restful APIs, Terraform, Data Pipelines, Serverless Computing, Docker, Agent2Agent Protocol - **Published:** November 3, 2026 - **Apply:** https://www.adzuna.co.uk/jobs/details/5951575119 ## About the Role The Principal Engineer role is ideal for an engineer archetype who * has a true full-stack ("any-stack") and polyglot mindset; * has a track record in building successful, mission-critical systems in non-trivial domains such as healthcare, finance, insurance, aviation, cybersecurity, and the like; * has (ideally) operated in both agile start-up environments and large(r) formal, regulated enterprises; * is an inspirational tech lead, leader, and catalyst, with a passion for guiding, supporting, and growing engineering organisations; and * is a true builder with deep passion for robust end-to-end software engineering, with deep expertise in the traditional praxis, and, ideally, the new, emerging AI SDLC and agentic praxis. Requirements Direct, demonstrable expertise and a track record in: * owning (designing, building, deploying, scaling, optimising, operating, and maintaining) and signing off non-trivial systems, services, platforms, and artefacts which satisfied heavy, long-horizon SLAs, SLCs, and SLOs, and met mission-critical client and regulatory requirements around stability, resilience, reliability, scalability, precision, quality, security, safety, observability, auditability, and verifiability, and the like; * provisioning, operating, and optimising fully cloud-native, cloud-first architectures and estates (must-have) and local, on-premise infrastructure (desirable); * designing, implementing, and sustaining robust, secure tech estates and zero trust architectures, auditable data pipelines, supply chain security, and organisation-wide SecOps and risk management processes that met formal security standards, certification, and verifiability; * leading multidisciplinary full-stack engineering teams, covering end-to-end back-end, front-end (incl. mobile), architectures, DevOps, infrastructure, DataOps, and SecOps (or a majority thereof); * mentoring, line-managing, and supporting engineering colleagues, and growing engineering organisations; * supporting and synchronising development streams and deliverables with ML scientists, data scientists, product managers, or operations teams; and * effective interaction and interfacing with senior management and domain experts in both technical and nontechnical domains. Additional Exposure Exposure to the following is highly desirable: * MLOps, data science, data analytics, classical ML, experiments, evaluation, and evidence-based optimisation; and * HealthTech, healthcare systems and products, and the wider NHS ecosystem. Tech Stack Demonstrable expertise in a good majority of the following: * advanced core Linux skills and administration; * languages and VMs: advanced Python (must-have) plus ideally substantial JVM (Java or Scala), .NET (C#), Rust, or Go expertise; Typescript and Javascript (must-have); Node.js (ideal); * APIs: RESTful APIs (must-have); GraphQL (desirable); MCP (desirable) or A2A (desirable); * web frameworks (Django (must-have)) and front-end frameworks (React (must-have), Blazor (desirable)); * mobile frameworks: React Native (highly desirable); * databases: both SQL (Postgres (must-have), SQL Server (desirable)) and NoSQL (MongoDB (desirable)); * cloud platforms, infrastructure, IaC, containerisation, and compute: AWS (must-have); Azure (desirable); Terraform (must-have) and policy as code; Docker (must-have); serverless architectures; sandboxes and enclaves; * GitOps and CI/CD pipelines; and * GenAI, LLMs, and agentic frameworks, APIs and SDKs (such as Anthropic, OpenAI, Google Gemini, Jev, LangChain, LangGraph, PydanticAI); agent sandboxes and enclaves; agent harnesses; and agent memory substrates., * A degree in a STEM subject: an undergraduate degree (must-have), a postgraduate degree (highly desirable), or a PhD (highly desirable). ## Description As our Principal Engineer, you will lead all core software engineering work across the entire Lantum platform and service architecture to scale Lantum's next stage of growth. You will work alongside our heads of AI/ML and product, healthcare domain experts, and Operations teams while staying hands-on to ship code to production yourself. The role is a true full-stack - "any-stack" - one, and covers back-end, front-end, architecture, infrastructure, DataOps, AI SDLC, and security realms and disciplines., As a Principal Engineer, * you own core, end-to-end software engineering processes and infrastructure; * you ensure that our existing core revenue-generating systems run without interruption under strict SLAs while optimising them, expanding their capabilities, and increasing cross-connectivity across our multi-product and services platform; * you protect sensitive operational healthcare data and financial information (as both assets and end-to-end data flows), and ensure that all systems, services, and artefacts meet strict regulatory criteria pertaining to security, observability, traceability, and verifiability; * you lead, support, and guide other engineers while synchronising build horizons with our wider multidisciplinary team; * design, build, operate, and secure agentic workflows, multi-agent systems, guardrails, security-first agentic architectures and topologies, and context flows; * you operate, optimise, and govern coding agents, software factories, and the use of wider AI tooling to enable reliable and precise AI FinOps and effective AI governance; and * you operationalise and optimise the next stage of Lantum's AI-native software development lifecycle that combines agentic loops with rigorous verifiability, observability, testing, and review processes.