Setting up your development environment

Before you start programming, you’ll need a code editor for C#. Microsoft has a family of code editors and integrated development environments (IDEs), which include:

• Visual Studio: Visual Studio 2026 for Windows. Visual Studio 2022 for Mac is no longer supported. You could also use Visual Studio in a virtual machine, or use Microsoft Dev Box as described at the following link: https://azure.microsoft.com/en-us/products/dev-box.
• VS Code: VS Code for Windows, Mac, Linux, the Web, or GitHub Codespaces.
• Rider: JetBrains Rider, which is available for Windows, Mac, or Linux. Since October 2024, it has a free version that you can read about at the following link: https://blog.jetbrains.com/dotnet/2024/10/16/rider-reveal-livestream-big-news-for-dotnet-and-game-devs/. Rider is popular with more experienced .NET developers.

Choosing the appropriate tool and application type for learning

What is the best tool and application type for learning how to use tools and skills with C# and .NET?

I want you to be free to choose any C# code editor or IDE to complete the coding tasks in this book, including Visual Studio, VS Code, Rider, or a code editor that I’ve never heard of.

In this book, I give general instructions that work with all tools, so you can use whichever tool you prefer.

Using Visual Studio for general development

Visual Studio can create most types of applications, including console apps, websites, web services, desktop, and mobile apps. Visual Studio only runs on Windows 10 version 1909 or later, or Windows Server 2016 or later, and only on 64-bit versions. Version 17.4 was the first version to support native ARM64.

Using VS Code for cross-platform development

The most modern and lightweight code editor to choose from, and the only one from Microsoft that is cross-platform, is VS Code. It can run on all common operating systems, including Windows, macOS, and many varieties of Linux, including Red Hat Enterprise Linux (RHEL) and Ubuntu. VS Code is a good choice for modern cross-platform development because it has an extensive and growing set of extensions to support many languages beyond C#.

Being cross-platform and lightweight, it can be installed on all platforms that your apps will be deployed to for quick bug fixes and so on. Choosing VS Code means a developer can use a cross-platform code editor to develop cross-platform apps.

VS Code is by far the most popular IDE, with over 75% of professional developers selecting it in the Stack Overflow 2025 survey, which you can read at the following link:

https://survey.stackoverflow.co/2025/technology/#1-dev-id-es.

Using GitHub Codespaces for development in the cloud

GitHub Codespaces is a fully configured development environment based on VS Code that can be spun up in an environment hosted in the cloud and accessed through any web browser. It supports Git repositories, extensions, and a built-in command-line interface so you can edit, run, and test from any device. Since it runs in the cloud and you interact with it via a web browser, there is nothing to download and install, and since it is based on VS Code, it works the same way VS Code does on your local computer.

Reviews of GitHub Codespaces are available at the following links:

• https://dev.to/github/github-codespaces-ga-any-good-reviewed-and-tested-3e62
• https://medium.com/@pooyan_razian/github-codespaces-a-different-way-to-code-da455777f9ab

Using Rider for cross-platform development

Rider is a third-party code editor from JetBrains, the maker of IntelliJ IDEA, the leading Java and Kotlin IDE, and ReSharper, the popular Visual Studio plugin for .NET developers. Rider runs on multiple platforms: Windows, macOS, and Linux.

Developers who use it are often professionals who appreciate the extra features it has like live code inspections, context actions, and refactorings. Using Rider can be an indicator of a more advanced developer.

You should expect new versions of Rider to support the latest version of .NET a few weeks after Visual Studio. For example, .NET 8 was released on November 14, 2023, and Visual Studio with official support for .NET 8 was released on the same day. But Rider version 2023.3 with official support for .NET 8 was not released until December 7, 2023.

Although JetBrains is a fantastic company with great products, both Rider and the ReSharper extension for Visual Studio are software, and all software has bugs and quirky behavior. For example, they might show errors like “Cannot resolve symbol” in your Razor Pages, Razor views, and Blazor components. Yet, you can build and run those files because there is no actual problem.

Will Microsoft merge Visual Studio and VS Code?

A reader, @automaton, posed a thought in the Discord channel for this book: “I wonder if the idea long term is to merge Code and VS.”

My best guess is that .NET developers on Windows will continue to prefer Visual Studio (this is likely about 70% of my readers), and everyone else will split between VS Code and Rider, especially now that Rider is free for non-commercial use.

Microsoft has been clear about their commitment to improving both Visual Studio and VS Code but keeping them distinct in their roles. While VS Code continues to be enhanced with new features and cross-platform capabilities, Visual Studio remains focused on being a best-in-class IDE for development on Windows.

Visual Studio is deeply integrated with Windows-specific technologies and APIs. It leverages components such as the Windows Presentation Foundation (WPF), which is not natively supported on other operating systems. Rewriting or adapting these dependencies for other platforms would require significant effort and resources.

My belief is that Microsoft will never port Visual Studio to other platforms or merge the two products. Instead, they will continue to add features from one to the other. For example, Solution Explorer has been added to VS Code, and HTTP Editor has been added to Visual Studio.

What I used

To write and test the code for this book, I used the following hardware and software:

• Windows 11 on an HP Spectre (Intel) laptop and a Microsoft Surface Laptop 7 (ARM) with Visual Studio, VS Code, and Rider.
• macOS on an Apple Silicon Mac mini (M1) desktop with VS Code and Rider.

I hope that you have access to a variety of hardware and software too, because seeing the differences on various platforms deepens your understanding of development challenges, although any one of the preceding combinations is enough to learn how to build practical apps and websites.

Deploying cross-platform

Your choice of code editor and operating system for development does not limit where your code gets deployed.

.NET 10 supports the following platforms for deployment:

• Windows: Windows 10 version 1607 or later, Windows 11 version 22000 or later, Windows Server 2012 R2 SP1 or later, and Nano Server version 2019 or later
• Linux: Alpine Linux 3.22, Azure Linux 3.0, CentOS Stream 9 or 10, Debian 12 or 13, Fedora 42, openSUSE Leap 15.6, RHEL 9 or 10, SUSE Enterprise Linux 15.6, and Ubuntu 22.04, 24.04, or 25.04
• Android: API 21 or later is the minimum SDK target. Versions 12, 12.1, 13, 14, and 15
• iOS and iPadOS: 18. iOS 12.2 is used as the minimum SDK target
• Mac: macOS 14 or 15

  You can review the latest supported operating systems and versions at the following link: https://github.com/dotnet/core/blob/main/release-notes/10.0/supported-os.md.

Downloading and installing Visual Studio

Many professional .NET developers use Visual Studio in their day-to-day development work. Even if you choose to use VS Code to complete the coding tasks in this book, you might want to familiarize yourself with Visual Studio too.

If you do not have a Windows computer, then you can skip this section and continue to the next section, where you will download and install VS Code on macOS or Linux.

Since October 2014, Microsoft has made a professional-quality edition of Visual Studio available to students, open-source contributors, and individuals for free. It is called Community Edition. Any edition is suitable for this book. If you have not already installed it, let’s do so now:

1. Download Visual Studio version 18.0 or later from the following link: https://visualstudio.microsoft.com/downloads/.

2. Start the installer.
3. On the Workloads tab, select the following:
   • ASP.NET and web development
   • .NET desktop development (because this includes console apps).
   • Desktop development with C++ with all default components (because this enables publishing console apps and web services that start faster and have smaller memory footprints).
4. On the Individual components tab, in the Code tools section, select the following:
   • GitHub Copilot
   • Git for Windows
5. Click Install and wait for the installer to acquire the selected software and install it.
6. When the installation is complete, click Launch.
7. The first time that you run Visual Studio, you will be prompted to sign in. If you have a Microsoft account, you can use that account. If you don’t, then register for a new one at the following link: https://signup.live.com/.
8. The first time that you run Visual Studio, you will be prompted to configure your environment. For Development Settings, choose Visual C#. For the color theme, I chose Light, but you can choose whatever tickles your fancy.
9. If you want to customize your keyboard shortcuts, navigate to Tools | Options…, and then select the Environment | Keyboard option.

Visual Studio keyboard shortcuts

In this book, I will avoid showing keyboard shortcuts since they are often customized. Where they are consistent across code editors and commonly used, I will try to show them.

If you want to identify and customize your keyboard shortcuts, then you can, as shown at the following link: https://learn.microsoft.com/en-us/visualstudio/ide/identifying-and-customizing-keyboard-shortcuts-in-visual-studio.

Downloading and installing VS Code

VS Code has rapidly improved over the past couple of years and has pleasantly surprised Microsoft with its popularity. If you are brave and like to live on the bleeding edge, then there is the Insiders edition, which is a daily build of the next version.

Even if you plan to only use Visual Studio for development, I recommend that you download and install VS Code and try the coding tasks in this chapter using it, and then decide if you want to stick with just using Visual Studio for the rest of the book.

Let’s now download and install VS Code, the .NET SDK, and the C# Dev Kit extension:

1. Download and install either the Stable Build or the Insiders edition of VS Code from the following link: https://code.visualstudio.com/.

2. Download and install the .NET SDK for version 10.0 from the following link: https://www.microsoft.com/net/download.

3. To install the C# Dev Kit extension using the user interface, you must first launch the VS Code application.
4. In VS Code, click the Extensions icon or navigate to View | Extensions.
5. C# Dev Kit is one of the most popular extensions available, so you should see it at the top of the list, or you can enter C# Dev Kit in the search box.
6. Click Install and wait for supporting packages to download and install.

Installing other extensions

In later chapters of this book, you will use more VS Code extensions. If you want to install them now, all the extensions that we will use are shown in Table 1.1:

Table 1.1: VS Code extensions used in this book

Managing VS Code extensions at the command prompt

You can manage VS Code extensions at the command prompt or terminal, as shown in Table 1.2:

Table 1.2: Working with extensions at the command prompt

For example, to install the C# Dev Kit extension, enter the following at the command prompt:

code --install-extension ms-dotnettools.csdevkit

Understanding VS Code versions

Microsoft releases a new feature version of VS Code (almost) every month and bug-fix versions more frequently. For example:

• Version 1.106.0, October 2025 feature release
• Version 1.106.1, October 2025 bug fix release

The version of VS Code is less important than the version of the C# extension. While the C# extension is not required, it provides IntelliSense as you type, code navigation, and debugging features, so it’s something that’s very handy to install and keep updated to support the latest C# language features.

VS Code keyboard shortcuts

In this book, I will avoid showing keyboard shortcuts used for tasks like creating a new file since they are often different on different operating systems. The situations where I will show keyboard shortcuts are when you need to repeatedly press the key, for example, while debugging. These are also more likely to be consistent across operating systems.

If you want to customize your keyboard shortcuts for VS Code, then you can, as shown at the following link: https://code.visualstudio.com/docs/getstarted/keybindings.

I recommend that you download a PDF of keyboard shortcuts for your operating system from the following list:

• Windows: https://code.visualstudio.com/shortcuts/keyboard-shortcuts-windows.pdf
• macOS: https://code.visualstudio.com/shortcuts/keyboard-shortcuts-macos.pdf
• Linux: https://code.visualstudio.com/shortcuts/keyboard-shortcuts-linux.pdf

Downloading and installing Rider

According to the Stack Overflow Survey, about 20% of professional C# and .NET developers use Rider in their day-to-day development work. Rider is cross-platform, so you can install and run it on Windows, macOS, and varieties of Linux. You can use an evaluation license key for a free 30-day trial.

JetBrains also offers Toolbox App to manage your IDEs easily and it’s free. It is especially useful for Linux users because Rider does not update through the apt (Advanced Package Tool) command like normal Linux programs. Plus, it gives you access to early access programs for software like JetBrains Fleet, a next-generation code editor.

If you have not already installed Rider and you want to use it, let’s do so now:

1. Download the latest version of Rider from the following link: https://www.jetbrains.com/rider/download/.

2. Run the installer.
3. Download the latest version of JetBrains Toolbox App from the following link: https://www.jetbrains.com/toolbox-app/.
4. Run the installer.
5. Navigate to https://visualstudio.microsoft.com/downloads/#build-tools-for-visual-studio-2026 and install the Build Tools for Visual Studio. These are necessary to use the native ahead-of-time (AOT) compiler.

   If you have installed JetBrains ReSharper in Visual Studio, you will get similar tools as in Rider.

Other JetBrains tools

JetBrains offers a suite of tools designed to enhance productivity, code quality, and application performance for .NET developers. A brief overview of dotPeek, dotTrace, dotMemory, and dotCover, highlighting their capabilities and benefits, is included in the following list:

• dotPeek: This tool can decompile .NET assemblies back to readable C# code, making it easier to explore and understand external code that lacks a source. It allows browsing the contents of assemblies, helping developers explore the structure and dependencies without needing the source code. It provides advanced navigation and search capabilities within decompiled code, such as quick jumping to symbol definitions and usages. It’s invaluable for understanding the inner workings of third-party libraries, frameworks, or any compiled .NET code without the original source. It can serve as a symbol server, making it possible to step into decompiled code during debugging sessions, aiding in the diagnosis of issues with external libraries. dotPeek is offered as a free tool, making advanced decompilation and assembly exploration accessible to all .NET developers.
• dotTrace: This tool provides detailed performance profiling for .NET applications, identifying performance bottlenecks by measuring execution times and call frequencies. It supports sampling, tracing, and timeline modes, each suited to different types of performance analysis. It offers a comprehensive set of views and filters to analyze the profiling data, including call trees, hot spots, and timeline views. It helps developers optimize application performance by pinpointing slow-running code and inefficient algorithms.
• dotMemory: This tool analyzes memory usage of .NET applications, identifying memory leaks and issues related to Garbage Collector (GC). It helps understand how memory is allocated and released, pinpointing excessive allocations that could lead to performance degradation. It allows the comparison of memory snapshots taken at different times, making it easier to identify memory leaks and the objects responsible. It facilitates memory optimization by providing insights into memory consumption patterns and detecting memory leaks.
• dotCover: This tool measures how much of the codebase is covered by tests, highlighting covered and uncovered code blocks. It works with various testing frameworks and supports all .NET applications, enhancing test effectiveness. It provides a continuous testing mode that automatically runs tests in the background as code changes, offering immediate feedback on test coverage and success. It helps improve code quality by ensuring higher coverage of tests, which can lead to fewer bugs and more stable applications. It facilitates an efficient testing process by identifying untested code, allowing developers to focus on areas lacking test coverage.

Together, these JetBrains tools form a comprehensive toolkit that can significantly enhance the productivity and efficiency of .NET development teams.