Quickstart: New App

Use this path when you are starting from an empty folder.

Goal

In 10 minutes, run a minimal Tessera app and verify your terminal/runtime are healthy.

1. Create the project

bash.sh

dotnet new console -n MyTesseraApp -f net10.0
cd MyTesseraApp

2. Install Tessera

bash.sh

dotnet add package Tessera

3. Replace Program.cs

csharp.cs

using Tessera;
using Tessera.Controls;
using Tessera.Layout;

var app = TesseraApplication.CreateBuilder()
    .UseApp<HelloApp>()
    .Build();

await app.RunAsync();

internal sealed class HelloApp : TesseraApp
{
    private readonly Button _button = new() { Text = "Press Enter" };
    private int _pressCount;

    public HelloApp()
    {
        _button.Activated += (_, _) => _pressCount++;
    }

    public override TesseraEffect? Update(Message message)
    {
        return message is KeyPressed key && key.IsCharacter('q', ModifierKeys.Ctrl)
            ? TesseraEffects.Quit
            : null;
    }

    public override Screen Build(ScreenContext context)
    {
        var status = new StatusBar
        {
            LeftText = $"Button presses: {_pressCount}",
            RightText = "Enter activates   Ctrl+Q quits"
        };

        return Screen.Build(window =>
        {
            window.Padding(1);
            window.Footer(1, status);
            window.Body(body => body.Center(_button, width: 20, height: 3));
        });
    }
}

4. Run

bash.sh

dotnet run

5. Success checklist

• app opens in your terminal without exceptions
• pressing Enter on the button increments the counter
• pressing Ctrl+Q exits cleanly

If one of these fails, go to Troubleshooting.

What to do next

1. Read Your First App for detailed explanation.
2. Run Starter Examples in order.
3. Use Widget Pages when you need control-by-control usage.