ASP.NET Core 3.0 will come with some changes in the way projects work with frameworks. The .NET Core integration will be tighter and will bring third-party open source integration.
Changes to shared frameworks in ASP.NET Core 3.0
In ASP.NET Core 1.0, packages were referenced as just packages. From ASP.NET Core 2.1 this was available as a .NET Core shared framework. ASP.NET Core 3.0 aims to reduce issues working with a shared framework. This change removes some of the Json.NET (Newtonsoft.Json) and Entity Framework Core (Microsoft.EntityFrameworkCore.*) components from the shared framework ASP.NET Core 3.0.
For areas in ASP.NET Core dependent on Json.NET, there will be packages that support the integration. The default areas will be updated to use in-box JSON APIs. Also, Entity Framework Core will be shipped as “pure” NuGet packages.
Shift to .NET Core from .NET Framework
The .NET Framework will get fewer new features that come to .NET Core in further releases. This change is made so that existing applications in .NET Core don’t break due to some changes. To leverage the features from .NET Core, ASP.NET Core will now only run on .NET Core starting from version 3.0.
Developers currently using ASP.NET Core on .NET Framework can continue to do so till the LTS support period of August 21, 2021.
Third party components will be filtered
Third party components will be removed. But Microsoft will support the open source community with integration APIs, contributions to existing libraries by Microsoft engineers, and project templates to ensure smooth integration of these components.
Work is also being done on streamlining the experience for building HTTP APIs, and a new API client generation system.
For more details, visit the Microsoft website.