Why should you care?

ShopNest wallet disputes need exact history of credits/debits, not only a balance column.

See it live — copy this example

Paste into a C# console or class library project and run dotnet run.

public abstract record WalletEvent(Guid WalletId);
public sealed record Credited(Guid WalletId, decimal Amount) : WalletEvent(WalletId);
public sealed record Debited(Guid WalletId, decimal Amount) : WalletEvent(WalletId);
public sealed class Wallet
{
    public decimal Balance { get; private set; }
    public void Apply(WalletEvent e)
    {
        switch (e)
        {
            case Credited c: Balance += c.Amount; break;
            case Debited d: Balance -= d.Amount; break;
        }
    }
}

var id = Guid.NewGuid();
var events = new WalletEvent[] { new Credited(id, 100), new Debited(id, 30) };
var wallet = new Wallet();
foreach (var e in events) wallet.Apply(e);
Console.WriteLine(wallet.Balance);

Run Example »

Edit the code below and click Run to see the result in Toolliyo’s live editor.

What happened?

• Events are facts; Apply rebuilds balance.
• Persist events; rebuild or snapshot for speed.
• Not every CRUD entity needs this.

Practice next

1. Fold the sample to 70.
2. Append another Credited and rebuild.
3. Store events in an append-only table.
4. Reject debit when balance insufficient.
5. Version event payloads.

Remember

State = fold of events. Append-only audit. Use where history matters.

ShopNest wallet stream

Support replays wallet events for a dispute.

Outcome: Exact timeline of every paisa movement.