The "Nexus" staging repo at Apache is being updated with rules for the .sha512
Currently, the rules don't recognize .sha512 as a file type that should *not* have a checksum, so you get errors saying there are unsigned artifacts, and it won't "close" the release at repository.apache.org. There's a fix for this, awaiting testing / deploying. I posted a comment to the Jira for that, asking when it might get done, and saying it's currently blocking releases for us. Here's the link to the comment: https://jira.apache.org/jira/browse/INFRA-14923?focusedCommentId=16654163&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-16654163 -Marshall
