Versioning your Model with NoSQL storage

I''m sure this topic has been discussed before, but if it has been, I can't
seem to find it through search. What I basically would like to know is how
people deal with versioning their domain model in relation to the storage
type they use, primarily in the case of using NoSQL storage mechanisms.

Versioning using a RDBMS has been a widely discussed topic because so many
people still use a RDBMS for their domain models in combination with some
ORM-framework. All sorts of guidance and tooling has been available for a
while, so I'm not interested in this kind of versioning. Moreover, domain
models are very well suited to store 'in a simpler way'.

It gets interesting when you choose to store your domain model/aggregates
using NoSQL alternatives, such as KeyValue-storage, by serializing your
aggregates into some sort of binary or json format or using plain files.
How do people cope with versioning in these cases? What if entire model
refactorings have to be made while you're already in production?

A few (real world) examples would be nice, thanks.