Azure Functions (isolated) project does not start via AddAzureFunctionsProject on macOS – no error, no output, port unavailable

[TomLederer]

I'm using a .NET 8/.NET 9 Azure Functions project with the isolated worker model and trying to run it via Aspire using builder.AddAzureFunctionsProject(...).

The project runs perfectly fine when executed directly via dotnet run or func start, including logging and breakpoints. However, when I try to run it through Aspire, the following happens:

No log output appears from the function app

• The configured port (e.g. 7071) is not opened
• The Aspire dashboard shows the function project as "Ready", but no requests can be sent to it
• The process appears to silently fail or exit, but Aspire gives no meaningful error
• In Aspire debug the process is shown with the PID 0
• This happens even with the official Aspire Azure Functions sample (https://github.com/dotnet/aspire-samples/tree/main/samples/AspireWithAzureFunctions), which I cloned and tested as-is.

Additional info:

• Happens with both .NET 8 and .NET 9 SDKs
• Running on macOS (Apple Silicon)
• Testing with both custom function apps and the official sample
• RIDER as IDE

[mikgam]

I'm also hitting this issue. @TomLederer, you closed this conversation/thread the same day you created it, did you find a solution?

Edit: disregard. I saw this other issue by you. #8374

[TomLederer]

Hi @mikgam . Yeah exactly, the issue was because of the IDE Rider...... When I started it via the terminal than everything was working just fine. Rider has some drawbacks here..... also the pure start of the Azure Functions Program had some issues within Rider... I switched to another IDE now since to many restrictions