I've begun using IStartup instead of a Bootstrapper. I've been told that
only one Bootstrapper should exist in one environment and the library that
I'm writing is not going to be the direct host so it should go into
IStartup.

I've done this but I need to move the below into IStartup:

Func<TinyIoCContainer, NamedParameterOverloads, IDocumentSession> factory = (ioccontainer, namedparams) => new DocumentSessionProvider().GetSession();

container.Register(factory);

In IStarup there are

IEnumerable<CollectionTypeRegistration> CollectionTypeRegistrations { get; }
IEnumerable<InstanceRegistration> InstanceRegistrations { get; }
IEnumerable<TypeRegistration> TypeRegistrations { get; }

Firstly I'm not sure which one I should put this logic into, I assume TypeRegistrations but then I'm not sure how to configure it to create a new TypeRegistration and pass in the Func. There does not seem to be any documentation on IStartup

Thanks