Principal / Lead Engineer - Python / Cloud / Terraform / IAM / DevOps / infrastructure-as-a-code IaC in London

Location: London / Hybrid x2 days

We are seeking an experienced Principal / Lead Engineer to join a highly ambitious organisation building a large-scale, mission-critical data and technology platform. This is a unique opportunity to join at the earliest stages of a major programme and play a key role in shaping its technical foundations.

Working closely with the CTO and a small team of senior engineers, you will lead the design and implementation of core infrastructure, establish engineering standards and practices, and make architectural decisions that will have long-term strategic impact. If you enjoy solving complex technical challenges, influencing technology strategy, and creating robust engineering foundations, this role offers an exceptional opportunity to make a lasting impact.

Role & Responsibilities

• Lead the design and implementation of foundational platform infrastructure and engineering capabilities.
• Define architectural patterns, engineering standards, and best practices that will guide future development.
• Partner closely with the CTO and senior stakeholders to make and document key technical decisions.
• Promote secure‑by‑design principles across all aspects of platform development.
• Establish and maintain core engineering tooling, including source control, CI/CD pipelines, infrastructure‑as‑code, and automated testing frameworks.
• Design and implement identity and access management solutions with robust authentication and authorisation controls.
• Build and manage cloud infrastructure using modern infrastructure‑as‑code approaches.
• Develop audit, workflow, and operational capabilities to support governance and compliance requirements.
• Implement networking, monitoring, and security controls for highly secure environments.
• Evaluate and integrate appropriate open‑source technologies and third‑party components.
• Contribute to the design and delivery of scalable, resilient, and maintainable distributed systems.
• Act as a senior technical contributor within a high‑performing engineering team.
• Mentor engineers and help establish a strong engineering culture as the organisation grows.
• Collaborate with product, design, and delivery teams to ensure technology solutions align with business objectives.
• Engage with external partners, suppliers, and stakeholders where required.

Proven experience

• Leading or making significant contributions to complex distributed, cloud‑native, or federated systems.
• Strong software engineering expertise in Python, including backend development, automation, and infrastructure tooling.
• Hands‑on experience with at least one major cloud platform (AWS, Azure, or Google Cloud).
• Strong experience implementing Infrastructure as Code using tools such as Terraform or equivalent.
• Experience designing and building authentication and authorisation systems, including modern identity standards and policy‑based access controls.
• Solid understanding of data storage architectures and the trade‑offs between different storage and query patterns.
• Experience establishing CI/CD pipelines and engineering best practices within modern software environments.
• Ability to work effectively in fast‑moving environments with evolving requirements and limited precedent.
• Strong communication skills with the ability to explain complex technical concepts to both technical and non‑technical audiences.
• Experience building secure, highly regulated, or mission‑critical platforms.
• Familiarity with federated architectures and distributed data access models.
• Experience designing solutions with strong governance, auditability, and security requirements.
• Knowledge of privacy‑preserving technologies and secure computing environments.
• Experience evaluating, adopting, or contributing to open‑source technologies.
• Background working within complex stakeholder environments undergoing significant transformation.