All you have to do is implement the same interfaces that the custom store uses for Identity.Entityframework .
User will be your user class.
public class MyUserStore<TUser> : IUserLoginStore<TUser, int>, IUserClaimStore<TUser, int>, IUserRoleStore<TUser, int>, IUserPasswordStore<TUser, int>, IUserSecurityStampStore<TUser, int>, IUserStore<TUser, int>, IDisposable where TUser : User { //Implement the interfaces you need }
Then pass MyUserStore to UserManager every request
new UserManager<User, int>(new MyUserStore<User>(new MyContext()))
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