Principal Python Developer // Derby (Onsite ) // £70,000 - £80,000 If you're looking for a Principal-level engineering role where you can drive real technical change while working on critical energy systems, keep reading! In this role you’ll still be building, but you'll also be making architecture decisions, coaching engineers, and guiding delivery standards across a growing digital capability. The focus is on backend Python systems that underpin the UK’s transition to sustainable, low-carbon energy. From secure APIs and cloud deployments to DevOps pipelines and data management, you’ll be responsible for ensuring high standards, modern engineering practices, and long-term scalability. What you’ll be doing: Driving technical direction across backend Python services (Django/Flask) Shaping cloud infrastructure on AWS, Azure or GCP using Terraform and Kubernetes Mentoring a cross-functional team of developers and engineers Working closely with product, DevOps, and senior stakeholders to align delivery Ensuring systems are secure, resilient, scalable and built with long-term maintainability in mind Who they’re looking for: Strong experience designing and building Python APIs in enterprise environments Comfortable with system architecture, DevOps tooling and infrastructure-as-code Cloud experience with AWS, Azure or GCP (preferably more than one) Someone who’s led teams or coached engineers, but still gets stuck into code Well-versed in Agile and CI/CD delivery – Git, automated testing, deployment pipelines Must be a sole UK national – SC clearance required Desirable extras: Experience with high-assurance or safety-critical software Exposure to GDS digital service standards Familiarity with big data, ETL, or ML/AI pipelines Background in energy, defence, embedded or industrial software a bonus Why this role? You’ll have real influence on how key infrastructure software is built and delivered The engineering culture is moving towards high trust, DevOps-first, cloud-native You’ll be working with experienced developers, architects, and delivery leads Long-term investment in your growth with clear routes into Head of Engineering or Enterprise Architecture roles Benefits: £70,000 to £80,000 basic salary Full-time onsite in Derby (due to project security and collaboration) Enhanced pension and private medical Annual holiday bonuses and a vibrant Employee Committee Huge investment in training, leadership coaching, and internal promotion Work that directly supports the UK's clean energy and net-zero goals For more information please apply now or contact job poster directly. *Sole UK Nationals only*