Join us at Totes as our Principal Software Engineer and play a leading role in driving innovation, technical excellence, and best practice across our growing engineering team. As a Principal Software Engineer, you’ll be at the heart of our technical delivery—designing, developing, and evolving the systems that power our business. You’ll lead by example, setting high standards for code quality, scalability, and maintainability while helping guide the technical direction of your squad and the wider engineering function. This is a hands-on role where you’ll design, build, and ship high-performance software using AWS, C#, .NET, and other modern technologies (Go, PHP, or JavaScript frameworks), while also mentoring others and influencing our product roadmap. What you’ll do: As a Principal Software Engineer, you’ll take the lead on key technical decisions within your squad, ensuring new features are delivered in harmony with sound architectural principles. You’ll own the full lifecycle of delivery—from initial insight and design through to development, testing, integration, deployment, and operation—ensuring that every solution you build is robust, scalable, and aligned with business goals. You’ll champion engineering excellence across the team, promoting best practices such as TDD/BDD, code reviews, and agile delivery. Collaboration will be key as you work closely with other Principal Engineers to share knowledge, resolve platform challenges, and continually improve the way we build software. As a leader and mentor, you’ll coach engineers at all levels, fostering a culture of learning, growth, and technical curiosity. You’ll also play an active role in shaping our technical roadmap, helping to steer the evolution of our products and platform. Beyond delivery, you’ll inspire innovation through demos, ‘brown bag’ sessions, and by exploring emerging technologies. Finally, you’ll be instrumental in sprint and program planning within our Agile framework, ensuring the team’s efforts are aligned with strategic objectives. What you’ll bring: You’ll bring proven hands-on experience with AWS, C#, .NET, and at least one additional language such as Go, PHP, or a JavaScript framework. Your deep understanding of cloud-native architectures, DevOps practices, and CI/CD pipelines means you can design, build, and maintain scalable, high-performance web applications with ease. You’ll have strong expertise in infrastructure as code, using tools like Terraform, AWS CDK, or CloudFormation, and a solid grasp of SOLID principles, databases, and performance optimisation techniques. Communication is one of your strengths; you can engage effectively with both technical and non-technical stakeholders. You’re a natural mentor and coach, passionate about developing others and leading by example. Above all, you have a growth mindset, constantly looking for innovative ways to improve, challenge the status quo, and drive meaningful change across the engineering function. What’s in it for you? At the Tote you can expect a friendly working environment with a strong sense of teamwork and pride in what we do. Within this role you’ll develop a broad range of skills and experiences that can enhance your career at the Tote. Additionally, our company benefits package includes; Competitive Basic Salary Discretionary Bonus Scheme Company Shares Option Plan Contributory pension scheme Life insurance (4 x basic salary) Simply Health Cash Plan Holiday entitlement (33 days inclusive of bank holidays) Study Support and opportunity for progression and development Confidential 24/7 365 employee assistance helpline Agile and collaborative office environment with free parking, fruit, biscuits, and drinks Regular social events, charity events and volunteering opportunities