Who are OnBuy? OnBuy are an online marketplace who are on a mission of being the best choice for every customer, everywhere. We have recently been named one of the UK's fastest-growing tech companies in Deloitte's Technology Fast 50 for the third year in a row (as well as 'Fastest-Growing Tech Business in the South West'). All achievements we are very proud of, but we don't let that go to our head. We are all laser focused on our mission and understand the huge joint effort ahead of us needed to succeed. Working at OnBuy: We are a team of driven and motivated people who thrive when working at pace. To succeed at OnBuy you need to take charge and fully own your responsibilities, rolling your sleeves up when needed to 'get it done'. Working at OnBuy you are surrounded by so much opportunity, but you must possess the ability to stay focused and prioritise ruthlessly. Most importantly, you will thrive in an ever-changing environment as we are constantly evolving. At OnBuy, you're not just a number or another cog in a machine. We are creating something really special, and you have the opportunity to affect meaningful change and have your voice heard. We are a close team, who have the opportunity to learn and grow as OnBuy evolves. We work in a flexible way, meaning we can prioritise our health and relationships, but when we are working, we graft. Job overview: As a Senior Site Reliability Engineer, you will play a critical role in ensuring our systems and environments are robust and reliable, with a high degree of observability, monitoring and alerting. You will help OnBuy build and maintain scalable, reliable systems while ensuring that our services meet the high standards of availability and performance expected by our users. Your expertise will be invaluable in automating and enhancing our operational processes, monitoring application performance, and troubleshooting complex issues. You will collaborate closely with software engineers to design reliable and efficient systems, participating in reliability reviews and driving best practices. Additionally, you will be responsible for creating and managing infrastructure as code, leveraging modern cloud technologies and tools. Your efforts will not only improve the uptime and efficiency of our services but also foster a culture of shared responsibility for system reliability. Key Responsibilities: Design and implement scalable systems to ensure high availability and performance. Develop automated solutions for monitoring, scaling, and system health management. Collaborate with software development teams to identify and resolve reliability issues. Create and maintain documentation related to system architecture, processes, and configurations. Perform incident response and postmortem analysis to improve site reliability and performance. Monitor system performance and make necessary adjustments to ensure optimal functionality. Implement and manage infrastructure as code using tools like Terraform or Ansible. This role requires out-of-hours support (via a rota) to address urgent DevOps issues, ensuring the reliability and availability of critical systems. Payment for this support is made via the companies ‘out of hours working’ policy’ Requirements Essential Proven experience as a Senior Site Reliability Engineer or in a similar role Strong proficiency in programming languages such as Python, Go, or Java. Experience with cloud service providers (AWS, Azure, Google Cloud) and container orchestration tools (Kubernetes, Docker). Solid understanding of networking, distributed systems, and microservices architecture. Familiarity with monitoring and logging tools (New Relic, Prometheus, Grafana, ELK stack, GCP logging). Excellent problem-solving skills and the ability to work effectively in a team. A strong determination and work ethic to find the best solution to any problem. Excellent problem-solving skills and the ability to work in a fast-paced, collaborative environment. Strong communication and interpersonal skills, with the ability to effectively collaborate with cross-functional teams. Benefits The salary range on offer for this role is £65,000 - £80,000 per annum, depending on experience. In return for helping us to grow, we’ll offer you company equity, meaning you own a piece of this business we are all working so hard to build.