DynamoVisualProgramming.DynamoServices by Autodesk

<PackageReference Include="DynamoVisualProgramming.DynamoServices" Version="3.4.0-beta6767" />

 IExtensionApplication

An FFI library can implement this interface to get some notifications from DesignScript application.
namespace Autodesk.DesignScript.Interfaces { internal interface IExtensionApplication { void StartUp(ExtensionStartupParams startParams); void OnBeginExecution(IExecutionSession session); void OnSuspendExecution(IExecutionSession session); void OnResumeExecution(IExecutionSession session); void OnEndExecution(IExecutionSession session); void ShutDown(); void PreloadAsmLibraries(string baseDirectory); } }