Worked on security hardening for the GeoscienceAustralia/dea-config repository by addressing S3 access controls within YAML configuration files. Focused on removing public-read ACLs and eliminating all s2 ACL references to enforce stricter bucket-level access policies, thereby reducing the risk of unintended public exposure of S3 objects. Utilized configuration management skills and expertise in YAML to implement these changes, which improved governance alignment and simplified audit processes across multiple environments. Maintained clear commit traceability with explicit messages to support future compliance reviews. The work centered on bug fixing rather than feature development, emphasizing careful, security-focused configuration management and documentation practices.