Restaurant Management System

At a Glance

The Problem

A restaurant client needed to replace paper-based order slips and spreadsheet shift reports with a single desktop application their staff could operate without training. Critical requirements: orders must reach the kitchen printer instantly without freezing the cashier screen, and end-of-shift cash reconciliation must catch discrepancies automatically.

The Solution

A full-featured WinForms POS with three dedicated role views — cashier, kitchen display, and manager dashboard. Kitchen ticket printing is offloaded to a background thread queue using ESC/POS socket commands, so the UI thread is never blocked. Shift closure enforces drawer entry against system totals and flags any variance above a configurable threshold.

Architecture

• →POS Terminal (Desktop): C# WinForms with SQL Server, barcode scanner integration, and keyboard-driven checkout for cashier speed.
• →Role Views: Cashier (order entry + billing), Kitchen Display (ticket queue + status), Manager Dashboard (sales charts + inventory + reports).
• →Background Print Broker: Dedicated Task.Run() worker dispatches ESC/POS commands over TCP to kitchen printers without touching the UI thread.
• →Shift Management: Role-scoped shift log enforces drawer reconciliation at close; variances are highlighted automatically.

Key Features

• ✓Complete order management — dine-in, takeaway, and delivery flows
• ✓Delivery zone management with driver dispatching and live order tracking
• ✓Shift-based cashier drawer reconciliation with automatic variance flagging
• ✓Asynchronous kitchen ticket printing (ESC/POS) via background thread queue
• ✓Live sales dashboard with daily revenue graphs (Chart controls)
• ✓Inventory stock-level tracking with low-stock alerts
• ✓Role-based permissions — Cashier, Kitchen, Admin
• ✓Modern dark-mode UI optimised for busy, high-throughput environments
• ✓Coupon and discount management
• ✓Database backup and restore utility

Screenshots

Code Highlight

// Prevents the cashier UI from freezing during printer I/O
public void QueueKitchenReceipt(KitchenReceipt receipt)
{
    Task.Run(() =>
    {
        try
        {
            using var printer = new EscPosPrinter(_settings.KitchenPrinterIp);
            printer.Initialize();
            printer.PrintText($"--- ORDER #{receipt.OrderId} ---");
            foreach (var item in receipt.Items)
                printer.PrintText($"{item.Quantity}x {item.Name} {item.Notes}");
            printer.CutPaper();
        }
        catch (Exception ex)
        {
            _logger.LogError("Kitchen printer failed: " + ex.Message);
            OnPrinterError?.Invoke(this,
                new PrinterErrorEventArgs(receipt.OrderId, ex.Message));
        }
    });
}

Challenges & Solutions

Tech Stack

What I Learned

• 💡Offloading ESC/POS print actions to background thread queues is essential — blocking the UI thread even for 200 ms noticeably disrupts cashier flow in a high-throughput environment.
• 💡Cashier ledger closures enforce financial transparency and simplify audit workflows — a feature most small POS systems skip but that pays for itself immediately in real operations.

Links