S3FS with versioning enabled on the S3 bucket would be a pretty low friction way to implement this. You'd also have to enable cross-region replication to deal with your "backups" being in the same place as your working copies. OpenVMS also has a versioning filesystem and a NFS server. The x64 version is available as a private beta, but it's not cheap. Personally, I just keep most stuff in a Google Drive folder and im…
S3FS can also be paired with MinIO (1) for a selfhosted solution. MinIO does apear to support versioning.
Also it appears VSI will offer free comunity licenses for OpenVMS x64 in the future (3).
(1) https://min.io
(2) https://min.io/product/object-versioning-bucket-versioning
(3) https://vmssoftware.com/about/news/2020-07-28-community-lice...