When I do a save of an entity with assigned id I get a

SharpArch.Core.PreconditionException: For better clarity and reliability, Entities with an assigned Id must call Save or Update

My class is

public class CompanyUserRepository :
RepositoryWithTypedId<CompanyUser, string>, ICompanyUserRepository
{
   public override CompanyUser SaveOrUpdate(CompanyUser entity)
   {
     var user = base.SaveOrUpdate(entity);
     //Do some stuff
     return user;
   }
}

How do I go about saving this entity?

RepositoryWithTypedId does not expose a Save method

Related question. This tells you the reason, but I haven't found out the Sharp Architecture way to do a Save.