public static SubscriptionBuilder <TSubscription, TOptions> UseCheckpointStore <TSubscription, TOptions, T>( this SubscriptionBuilder <TSubscription, TOptions> builder ) where T : class, ICheckpointStore where TSubscription : EventStoreCatchUpSubscriptionBase <TOptions> where TOptions : CatchUpSubscriptionOptions { builder.Services.TryAddSingleton <T>(); return(builder.AddParameterMap <ICheckpointStore, T>()); }