Can't use complex type as input & output with ActivityTrigger Attribute

[NielsFilter]

I'm testing out durable tasks using isolated function in .NET 7

I seem to be having trouble building to project when I have a complex type as inputs parameters or return types for my activity functions.

[Function("CalculateBuyProbability")]
public static async Task<SentimentResult> Calculate([ActivityTrigger] int userId, ILogger log)
{
    ...
}

...

[Function("PrintReport")]
public static async Task Print([ActivityTrigger] List<SentimentResult> results, SentimentResult test, ILogger log)
{
   ...
}

SentimentResult here is a basic complex type

public class SentimentResult
{
    public int UserId { get; set; }
    public int Sentiment { get; set; }
}

I get build error:
C:\Users\niels\RiderProjects\TestApps\Company.FunctionApp1\Company.FunctionApp1\Microsoft.DurableTask.Generators\Microsoft.DurableTask.Generators.DurableTaskSourceGenerator\GeneratedDurableTaskExtensions.cs(13,33): error CS0246: The type or namespace name 'SentimentResult' could not be found (are you missing a using directive or an assembly reference?) [C:\Users\niels\RiderProjects\TestApps\Company.FunctionApp1\Company.FunctionApp1\Company.FunctionApp1.cspro
j]

What I've tried:

• Removing the ActivityTriggerAttribute fixes the build error
• Returning object instead of complex type fixes the build error

I'm using Rider as my IDE, but I don't think it's related as dotnet build via terminal returns the same.

In case it matters, my csproj with the package versions I'm using:

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <TargetFramework>net7.0</TargetFramework>
        <AzureFunctionsVersion>V4</AzureFunctionsVersion>
        <OutputType>Exe</OutputType>
        <ImplicitUsings>enable</ImplicitUsings>
        <Nullable>enable</Nullable>
    </PropertyGroup>
    <ItemGroup>
        <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.11.0-preview2" />
        <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.DurableTask" Version="0.4.1-beta" />
        <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.0.13" />
        <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.8.0-preview2" />
    </ItemGroup>
    <ItemGroup>
        <None Update="host.json">
            <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
        </None>
    </ItemGroup>
</Project>

[NielsFilter]

I see this was already logged here: #35 Closing the issue