Currently ArtifactManager is configured via system properties and environment variables. It is not comfortable for automation purposes, because one would need to setup them for any container for testing purposes. https://github.com/jenkinsci/artifact-manager-s3-plugin/blob/master/src/main/java/io/jenkins/plugins/artifact_manager_s3/JCloudsArtifactManager.java

• Minimum: Make the fields non-final so that the settings can be configured via Groovy hook scripts
• Nice2Have: Add support of proper UI AND allow configuring ArtifactManagerFactory via DataBoundSetters. It would allow using Configuration-as-Code plugin and other such tools