Chaos Engineering

Prerequisite: Familiarity with the concepts introduced in Part 3 — Data Layer Tidb. Review it first if the terminology in this part is unfamiliar. Answer-first: Ensuring 99.99% availability for payment systems demands proactive SRE practices and automated Chaos Engineering. Injecting synthetic latency, pod failures, and network partitions via Chaos Mesh validates microservice circuit breakers before real production incidents occur. Answer-first: PayPay ensures system resilience by executing automated chaos engineering experiments in staging environments using tools like Chaos Mesh. Injecting artificial network latency, pod failures, and disk I/O bottlenecks allows SRE teams to verify that failover protocols activate without compromising transaction consistency. ...

PayPay Architecture: Scaling to 70M Users & 100k Peak TPS PayPay launched in October 2018 and grew to 10 million users in just 3 months — a growth rate that no Japanese fintech had ever seen. By 2025, the platform had crossed 70 million registered users and processed 7.8 billion payments per year. Behind this growth is an engineering team that has had to scale not just their infrastructure, but their entire engineering culture: from service standardization and GitOps-driven deployments to chaos engineering and AI-powered fraud detection. ...