Staff Site Reliability Engineer

Meet: Pay.com.au
Founded: 2019Employees: Crica 200Funding: Raised approximately US$70 million in total fundingLocation: Windsor, MelbourneWays of working: Hybrid, office 3 days a week (Mon, Tues & Thurs)
The Story
pay.com.au is one of the fastest-growing fintechs in Australia, already trusted by 100,000+ businesses to manage their payments, bills and expenses. The platform is processing billions of dollars a year, growing at roughly 80% year on year, with a fresh US$28M raise now fuelling US expansion. It's the kind of stage where the fundamentals start to matter more than ever, and reliability is becoming a genuine business priority.
The Role
This is a brand new Staff Engineer role. No incumbent, no existing playbook. You'll be the senior owner for SRE, AWS infrastructure, observability and incident management across engineering: building the reliability charter from scratch, standing up proper on-call and incident response, turning a newly rolled out Datadog investment into a real observability practice, and working with teams to establish SLIs and error budgets where none exist today. You'll stay hands-on, writing code and shaping infrastructure yourself, while lifting how the wider engineering team thinks about production risk.
The stack is AWS end to end, deployed through Terraform, with a fairly serverless architecture built on Lambda and ECS. Datadog has just landed. Cost optimisation and AWS monitoring are still open ground, so there's a FinOps practice to build here too if that's an itch you want to scratch.
Why This Is Interesting
Real scale, real stakes. pay.com.au processed $10B+ in TTV last year and is aiming for immense growth. This isn't legacy debt to untangle either: there's no existing SRE process, on-call rotation or observability discipline to fit into, so you get to decide what good actually looks like. You'll work closely with the CTO at a formative point for how the platform function gets built, with room to influence architecture and engineering practice well beyond the SRE remit.
Put simply: this is a strong fit for someone who wants to point at something afterwards and say they built it, not just that they held a title while it existed.
Who Should Apply
Engineers who've owned an SRE or reliability charter end to end before: assessing the risk, building the plan, and doing the work to close the gap yourself. You're comfortable in AWS, ideally with serverless (Lambda, ECS) and Terraform, and you've built incident management and observability practice from a low baseline rather than just operating inside someone else's. Fintech experience isn't required. What matters more is judgment, a hands-on approach, and being someone who can turn an undefined problem into a plan people actually trust.
Next steps
Hi 👋 I’m Breanna from affix. If this role resonates with you, then let's make time to connect! I'd love to make time to chat, tell you more about the exciting journey that pay.com.au is on, and see if this is a great fit for you!