Site Reliability Engineering (SRE) combines software and systems engineering to build and run large-scale, massively distributed, fault-tolerant systems. SRE ensures that Google Cloud's services—both our internally critical and our externally-visible systems—have reliability, uptime appropriate to customer's needs and a fast rate of improvement. Much of our software development focuses on optimizing existing systems, building infrastructure and eliminating work through automation. SRE's culture of intellectual curiosity, problem solving, and openness is key to its success. We encourage collaboration, big thinking, risk-taking, and provide an environment of support and mentorship for learning and growth.