This sample is to demonstrate a bug with Azure WebJobs SDK (specifically, building an Azure Function) that appears when using both extension bundles (https://docs.microsoft.com/en-us/azure/azure-functions/functions-bindings-register#local-development-with-azure-functions-core-tools-and-extension-bundles) combined with dependency injection (https://docs.microsoft.com/en-us/azure/azure-functions/functions-dotnet-dependency-injection)

IMPORTANT: In order to properly run this sample, you must edit local.settings.json and specify a valid connection string for AzureWebJobsStorage.

You must then install Azure Functions Core Tools using the instructions here: https://docs.microsoft.com/en-us/azure/azure-functions/functions-run-local#install-the-azure-functions-core-tools

Then run the following command from the project directory: func host start

You will notice that the Startup function is never called since the message "Startup has been called!" is never printed.

You can work around the bug simply by removing the extensionBundle from host.json after running the Azure Function Host for the first time.