Document plug-in APIs (#4473)

Part of #1920

entity-framework/core/miscellaneous/plugins.md

@@ -0,0 +1,37 @@
+---
+title: Plug-in APIs - EF Core
+description: APIs extensions can use to plug into certain Entity Framework Core components
+author: bricelam
+ms.date: 8/31/2023
+uid: core/miscellaneous/plugins
+---
+# Plug-in APIs
+
+EF Core extensions often require adding logic to core EF and provider components. This usually requires creating a derived component and replacing the original one in the internal service provider. This gets complicated when multiple extensions want to change the same component. In these cases, we provide plug-in APIs to allow multiple extensions to provide additional logic.
+
+## List of services
+
+The following is a list of plug-in APIs.
+
+Service                                                                                       | Description
+--------------------------------------------------------------------------------------------- | -----------
+<xref:Microsoft.EntityFrameworkCore.Storage.ITypeMappingSourcePlugin>                         | Adds mappings between .NET types and primitive store types.
+<xref:Microsoft.EntityFrameworkCore.Storage.IRelationalTypeMappingSourcePlugin>               | Adds mappings between .NET types and primitive relational database types.
+<xref:Microsoft.EntityFrameworkCore.Metadata.Conventions.Infrastructure.IConventionSetPlugin> | Adds model building conventions.
+<xref:Microsoft.EntityFrameworkCore.Query.IMemberTranslatorPlugin>                            | Adds SQL translations for .NET properties.
+<xref:Microsoft.EntityFrameworkCore.Query.IMethodCallTranslatorPlugin>                        | Adds SQL translations for .NET methods.
+<xref:Microsoft.EntityFrameworkCore.Query.IAggregateMethodCallTranslatorPlugin>               | Adds SQL translations for .NET enumerable methods.
+<xref:Microsoft.EntityFrameworkCore.Query.IEvaluatableExpressionFilterPlugin>                 | Forces server-eval of certain expressions.
+<xref:Microsoft.EntityFrameworkCore.Scaffolding.IProviderCodeGeneratorPlugin>                 | Scaffolds provider and DbContext options.
+
+## Examples
+
+Here are some extensions making use of these APIs:
+
+Extension | Description
+--------- | -----------
+[Microsoft.EntityFrameworkCore.Sqlite.NetTopologySuite](https://github.com/dotnet/efcore/tree/main/src/EFCore.Sqlite.NTS) | Adds type mappings and SQL translations for SpatiaLite's types.
+[Microsoft.EntityFrameworkCore.SqlServer.HierarchyId](https://github.com/dotnet/efcore/tree/main/src/EFCore.SqlServer.HierarchyId) | Adds type mappings and SQL translations for SQL Server's hierarchyid type.
+[Microsoft.EntityFrameworkCore.SqlServer.NetTopologySuite](https://github.com/dotnet/efcore/tree/main/src/EFCore.SqlServer.NTS) | Adds type mappings and SQL translations for SQL Server's geography and geometry types.
+[EFCore.CheckConstraints](https://github.com/efcore/EFCore.CheckConstraints) | Adds model building conventions for relational database check constraints.
+[EFCore.NamingConventions](https://github.com/efcore/EFCore.NamingConventions) | Adds model building conventions for alternative relational database table, column, and constraint names.

entity-framework/toc.yml

@@ -368,6 +368,8 @@
         href: core/miscellaneous/context-pooling.md
       - name: Support multi-tenant databases
         href: core/miscellaneous/multitenancy.md
+      - name: Plug-in APIs
+        href: core/miscellaneous/plugins.md
 
     - name: Database providers
       items: