// side projects & experiments

.NET 10 Console Demo

A hand-written console app exploring the newest C# 14 and .NET 10 language features — extension members, partial constructors, field-backed properties and more.

#dotnet #csharp #project
The .NET 10 Console Demo running in the terminal, showing an ASCII banner and a menu of examples

Published 12/09/2026 · 2 min read

View on GitHub

Table of contents

Overview

This one is a small console app I built by hand — no AI involved, just me and Neovim on macOS. It’s a .NET 10 console app with some of the latest C# features. Pick an example from the list, see the file source code and watch it run. Nothing fancy, but it does the job of making a new language feature displayed as a reference.

What’s inside

  • Extension members — the new extension(string value) { ... } block syntax, used here to add an IsEmpty property and a Reverse() method onto string.
  • Partial constructors — a partial class declaring public partial ConstructorExample(); in one half and implementing it in the other.
  • Field-backed properties — the field keyword for a property that needs to touch its backing field without declaring one explicitly.
  • Lambda parameter modifiers without explicit types — ref, in and out on lambda parameters, inferred rather than spelled out.
  • Span<T> and Memory<T> — stack-allocated buffers, zero-allocation substrings, and the Memory<T> fallback for the async cases where Span<T> can’t go.
  • Examples are discovered by reflection (anything implementing IExample) and wired up through a plain ServiceCollection — no web host needed for a console app to enjoy DI.
  • Graceful shutdown on both Ctrl+C and SIGTERM via PosixSignalRegistration.

Notes

I’ve add a screenshot from my Neovim coding session to the github repo too.