We are in the process of adapting our build & release procedure of one of our Java based products to support patch / hotfix releases.
Today, we deliver a full installation package (which is a set of RPM packages wrapped in an ISO) out of our build pipeline. However, we aim to also support incremental / more fine grained upgrade / patch shipments as well.
To keep things simple as an initial step, we plan to have more fine-grained RPM packages and package a subset (only the changed ones in the scope of a release) of these RPMs in a dedicated hotfix ISO along with the full installation ISO. (We have also considered other options like binary diff - delta RPMs - creating a separate hotfix RPM etc.)
I would like to hear about how you manage your build pipeline - packaging and version control (as this is in the core a release management issue as well) in order to support this kind of hotfix deployments?