Introduction
Since its initial release back in 2002, the .NET Framework has grown to become one of the most popular development platforms in the world. However, as software trends and technologies advanced, Microsoft realized it was time for a reboot of the .NET platform. This is where .NET Core comes in.
In this blog post, we'll explore what .NET Core is, how it differs from the traditional .NET Framework, and why it represents the future direction for all .NET development. We'll discuss the key benefits and features that make .NET Core so compelling. By the end, you'll understand why Modern .NET apps are now being built on .NET Core instead of the legacy Framework.
What is .NET Core?
.NET Core is a cross-platform, open-source implementation of .NET. It was designed and built by Microsoft from the ground up to be modular, lightweight, and cloud-focused. Some key differences from the classic .NET Framework include:
- Cross-Platform: .NET Core can be run on Windows, Linux, and macOS. This allows .NET apps to work everywhere.
- Lightweight: Only includes functionality required for core web and CLI scenarios. Much smaller footprint than the legacy .NET Framework.
- Modular: Core components and frameworks are delivered independently via NuGet packages. Can pick and choose what is needed.
- Open Source: .NET Core is fully open source under the MIT license. The community can contribute to the evolution of the platform.
- Cloud-First: Purpose-built for building modern cloud apps that scale effectively in containers and serverless environments.
Instead of revolutionizing the classic .NET with cross-platform features, Microsoft smartly chose to rebuild .NET from the ground up, specifically for web and container workloads on Linux and Windows. This has resulted in numerous benefits.
Benefits of .NET Core
There are many compelling advantages that come with developing apps on .NET Core instead of the older .NET Framework:
- Cross-Platform Support: The ability to share codebases and deploy apps on any OS eliminates vendor lock-in. Great for microservices.
- Performance: Slimmer payload enables faster startups. Just-in-time compilation delivers near-C compatibility without sacrificing developer productivity.
- Agility: The modular package-based model allows granular updating. Faster iteration when not tied to giant monolithic framework releases.
- Cloud-Native: Built for container-based deployments to Kubernetes and serverless hosting. Scales easily on modern infrastructure.
- Open Source Advantages: Transparent governance invites community input. Can inspect sources, fix issues directly, and participate freely in development.
- Cost Savings: Reduced licensing costs by running on Linux. Reuses existing skills rather than learning new languages.
- Unified Story: Single .NET implementation going forward means developer energy is not split between frameworks.
Ease of use, performance, and suitability for cloud-native scenarios and container platforms make .NET Core the future of efficient, productive .NET application development.
Key .NET Core Concepts
To take full advantage of .NET Core's capabilities, developers need an understanding of some foundational elements:
- CLI Tools: .NET Core Command Line Interface (CLI) provides common utilities for tasks like building, publishing, restoring packages, etc.
- CoreFX: Defines core .NET types used in all .NET apps like System, Collections, IO, Linq, and Reflection.
- CoreCLR: Lightweight, cross-platform runtime that executes .NET code, provides garbage collection, and JIT compilation.
- SDK: Software Development Kit bundles CLI, CoreFX, and dependencies for building applications easily.
- NUGET: Package manager for assemblies and dependencies is built-in to restore libraries as projects are built.
- Project/Code Organization: Projects now follow a directory structure with .csproj files rather than old project files.
- Target Framework Monikers: Unambiguous identifiers for runtime and SDK versions like "net6.0" instead of "Framework 4.x".
Understanding the role and relationship between these core building blocks is essential for optimally structuring code and dependencies in the modern .NET ecosystem.
Popular .NET Core Technologies
With thousands of NuGet libraries available, the ecosystem around .NET Core has flourished with many productivity-boosting additions:
- ASP.NET Core: Fundamental framework for building web APIs and MVC web applications using Model-View-Controller pattern.
- Entity Framework Core: ORM, born on .NET Core, provides simplified data modeling capabilities with POCO modeling and migrations.
- Blazor: Let developers create interactive web UIs using C# instead of JavaScript. Runs natively in the browser or as a hosted web assembly app.
- gRPC: Open source framework enabling REMOTE procedure calls across languages and platforms through IDL interface definitions and shared protocol buffers.
- ML.NET: Open source machine learning framework allows building intelligent applications with APIs for training models on diverse data.
- Docker Integration: Create containers for self-contained and portable deployment of .NET Core apps using Dockerfiles.
- Kubernetes Support: Ability to publish and scale microservices on Kubernetes clusters for hybrid and multi-cloud deployments.
- Azure Integration: Seamless hosting on Azure App Service, Functions, and Kubernetes Service with familiar .NET APIs.
This rich ecosystem has expanded the capabilities of .NET Core far beyond its initial scope, making it the de facto choice for greenfield application development.
Adoption and Future Roadmap
Since its introduction in 2016, the adoption of .NET Core has grown tremendously in both enterprise and indie developer communities seeking modern language benefits. Some milestones:
- .NET Core 2.0 brought support for traditional Windows desktop apps in 2017.
- .NET 5 in 2020 unified .NET Core, Framework, and Xamarin into the single base library and runtime called .NET 5.
- LTS releases every 2 years and provides long-term support. The current is .NET 6 (Nov 2021), with .NET 7 planned for Nov 2022.
Looking ahead, Microsoft continues to evolve .NET Core in exciting new areas:
- new language features: C# 10 and records, top-level programs
- UI frameworks: Blazor Desktop, MAUI for mobile/desktop
- Cloud support: Serverless computing, containers, Kubernetes
- ML enhancements: Computer vision, NLP, recommendations
- Better developer tools: Visual Studio for Mac, Codespaces in the browser
Clearly, .NET Core has firmly established itself as the strategic path forward. With Microsoft fully committed long term, it offers unparalleled prospects for development on modern full-stack frameworks well into the future. For new and existing, Hire top .NET developers migrating to .NET Core makes total sense.