Maryana Bucknell upgraded the Argo CD deployment within the adfinis/helm-charts repository, focusing on the infra-apps Helm chart to enhance stability and governance. She updated Argo CD from version 3.1.3 to 3.1.8 and increased the targetRevision in values.yaml, ensuring compatibility with newer releases. The work involved careful modification of YAML configuration files and documentation updates in Chart.yaml and README.md to reflect the changes and release notes. Using her expertise in DevOps, Helm, and Argo CD, Maryana delivered a focused feature upgrade, demonstrating depth in version management and configuration best practices over a one-month development period.