i have just published a small package that i hope some will find useful.
Actually, when you are creating a local (unmanaged) client only collection, the collection is not persisted when a hot code push happens. This package allow those collections to be migrated after a hot code push.
The goal for this change is to enable local collections as a mean to store session state, in a way more homogenous with the other data sources (mongo on client and server).
The package is here https://atmospherejs.com/vjau/localcollections-persister
Comments and suggestions welcome.