From firefighting to future-proofing: Atlassian’s journey with a multi-account strategy

This post details the 'Account Sharding' project to re-design Atlassian's internal cloud platform (Micros) to address scaling issues caused by hitting AWS account limits. It explains the problem of AWS resource and API limits, the impact on deployments and developer experience, and the decision-making process for adopting a multi-account strategy. The strategy involves incrementally adding accounts, analyzing data to adjust decisions, and avoiding immediate evacuation of services from existing accounts due to migration complexity. The post highlights the challenges of resource migration (compute, ephemeral, persistent) and the decision to involve service owners minimally.