What's New in .NET 8

Welcome to the comprehensive overview of the exciting features and improvements introduced in .NET 8. This release brings significant advancements across the .NET platform, focusing on performance, productivity, and new capabilities for building a wide range of applications.

Key Highlights

Performance Optimizations: Enhanced runtime performance, improved garbage collection, and faster JIT compilation.
C# 12 and .NET CLI Enhancements: New language features in C# 12 and streamlined command-line tooling.
ASP.NET Core 8: Major updates including Blazor Server and Blazor Web App improvements, minimal APIs, and enhanced authentication.
.NET MAUI: Continued improvements in cross-platform UI development for mobile and desktop.
Native AOT: Further advancements in Ahead-Of-Time compilation for smaller, faster, and more secure native executables.
WebAssembly (Wasm): Improved performance and tooling for running .NET applications in the browser.

Performance and Scalability

Performance is a cornerstone of .NET 8. Significant work has been done to optimize the .NET runtime and libraries, resulting in:

Faster startup times for applications.
Reduced memory consumption through more efficient resource management.
Higher throughput for concurrent operations.

Runtime Optimizations

The JIT compiler and GC have received substantial tuning. Expect improvements in:

Region-based GC for more predictable pauses.
Improved SIMD support for vectorized operations.
Faster method dispatch and object allocation.

Productivity and Development Experience

.NET 8 aims to make developers more productive with new language features and tooling updates.

C# 12 Features

C# 12 introduces several powerful new features:

Primary Constructors: Simplify class and struct declarations.
Collection Expressions: A more concise syntax for creating collections.
Default Lambda Parameters: Define default values for lambda parameters.
Inline Arrays: Enable the use of fixed-size arrays directly within types.
`ref readonly` parameters: Improve performance and safety for passing large structs.

            // Example of Primary Constructors in C# 12

            public class Person(string name, int age) {

                public string Name { get; } = name;

                public int Age { get; } = age;

            }

.NET CLI Improvements

The .NET command-line interface (CLI) continues to evolve:

Streamlined project creation and management commands.
Enhanced debugging and profiling capabilities.
Improved support for cross-platform development.

Web Development with ASP.NET Core 8

ASP.NET Core 8 brings significant advancements for building modern web applications.

Blazor Enhancements

Blazor Web App offers a unified model for building interactive web UIs:

Server and WebAssembly rendering modes integrated.
Improved component lifecycle and state management.
Enhanced routing and navigation.

Minimal APIs

Minimal APIs are further refined, offering a lightweight and productive way to build HTTP services.

            // Example of a Minimal API endpoint

            var builder = WebApplication.CreateBuilder(args);

            var app = builder.Build();

            app.MapGet("/", () => "Hello World!");

            app.Run();

Native AOT and Cloud-Native

.NET 8 continues to push the boundaries of native compilation and cloud-native development.

Native AOT Improvements

Native Ahead-Of-Time (AOT) compilation offers substantial benefits:

Smaller deployment sizes.
Faster application startup.
Reduced attack surface.
Improved memory footprint.

Support for Native AOT has been extended to more scenarios, including ReadyToRun (R2R) compilation for improved startup performance when full Native AOT is not feasible.

Containerization

.NET 8 images are optimized for containerized environments, with smaller base images and improved build times.

Learn More

Dive deeper into the specifics of each feature: