Storing State/Serialized Object


What’s the most appropriate way to store state in Atom?

The package I’m working on right now needs to store when people get an achievement:

Is there a way to store a serialized object for a package, preferably as an Atom built in?

Persistence options for packages

The serialization doc appears to have just what I need.

registerDeserializer is not global like mentioned in the doc though.