Repository.cs

public class WarehouseProductRepository
{
    private readonly Dictionary<string, List<IEvent>> _inMemoryStreams = new();

    public WarehouseProduct Get(string sku)
    {
        var warehouseProduct = new WarehouseProduct(sku);

        if (_inMemoryStreams.ContainsKey(sku))
        {
            foreach (var evnt in _inMemoryStreams[sku])
            {
                warehouseProduct.ApplyEvent(evnt);
            }
        }

        return warehouseProduct;
    }

    public void Save(WarehouseProduct warehouseProduct)
    {
        if (_inMemoryStreams.ContainsKey(warehouseProduct.Sku) == false)
        {
            _inMemoryStreams.Add(warehouseProduct.Sku, new List<IEvent>());
        }

        var newEvents = warehouseProduct.GetUncommittedEvents();
        _inMemoryStreams[warehouseProduct.Sku].AddRange(newEvents);
        warehouseProduct.EventsCommitted();
    }
}