Tracking .NET 8 Support

[normj]

Update 2/22/2024

The .NET 8 Lambda runtime has been released.

https://aws.amazon.com/blogs/compute/introducing-the-net-8-runtime-for-aws-lambda/

---

Completed Tasks

• Amazon.Lambda.RuntimeSupport, the Lambda runtime client, has been updated for .NET 8 including making the assembly trimmable for .NET 8.
• Use new .NET 8 APIs in Amazon.Lambda.RuntimeSupport to ensure the .NET runtime understands the amount of memory allocated to the function Use the new .NET 8 APIs to configure max heap memory size #1578
• Event packages have been updated for .NET 8 including making the assemblies trimmable for .NET 8.
• .NET CLI Lambda template updated to have custom runtime templates target .NET 8 and use the provided.al2023 runtime.
• Amazon.Lambda.Annotations has been updated to support building as an executable assembly. AOT trimming warnings have also been addressed. This allows you target .NET 8 and deploy either as a self contained executable or AOT. A new project template using this feature, more documentation updates and a .NET 8 Lambda build image for AOT will be coming. Checkout James Eastham video on how to use this feature now: https://www.youtube.com/watch?v=kyb16r-Oul0
• .NET 8 version of the .NET Mock Lambda Test Tool has been released.
• The .NET 8 OCI image has been published to ECR https://gallery.ecr.aws/lambda/dotnet
  • public.ecr.aws/lambda/dotnet:8
• .NET 8 build image used for container builds especially Native AOT builds has been released https://gallery.ecr.aws/sam/build-dotnet8
• Amazon.Lambda.Tools has been updated to use the .NET 8 build image unless override by the --container-image-for-build switch. Amazon.Lambda.Tools will automatically use container builds when building for Native AOT to use matching Amazon Linux 2023 build environment.
• Amazon.Lambda.AspNetCoreServer and Amazon.Lambda.AspNetCoreServer.Hosting have been updated to target .NET 8 and support Native AOT trimming.
• Amazon.Lambda.Templates 7.0.0 has been released targeting the .NET Lambda templates to .NET 8.
• Managed .NET 8 Lambda runtime using the identifier dotnet8 has been released.

[petro2050]

Thanks for tracking this. Just to clarify, should we expect all Amazon.Lambda.* packages to be .NET 8 compatible when support is ready?

Also, looking at the completed tasks, it seems a lot has already been done. How much work is remaining?

[normj]

Hi @petro2050

I avoided making a list of what needs to be done because that might imply it is a finite list and as we know with software as we go through things new things and ideas pop up. The long poll task is deploying the managed runtime which requires a lot of operational tasks to make sure everything is in place so it can be well monitored and supported.

From the Amazon.Lambda.* perspective most everything has been verified for .NET 8. The outstanding libraries that still need to be verified is the ASP.NET Core bridge library Amazon.Lambda.AspNetCoreServer and our Amazon.Lambda.Annotations library. We are also working with the SAM team that produce the build container images to get a .NET 8 container image released. That will using Native AOT with .NET 8 a lot easier.

[Simonl9l]

@normj we appreciate that you are on top of this, as some IDE developers are significantly behind the eight ball on support.

[normj]

Updated descriptions with some info on getting started now without managed runtime.

[skirk-mpr]

Thank you for the information and the updates, @normj! We are really looking forward to this and appreciate it!

[jakenuts]

For projects currently deployed "as-is" on the AWS::Serverless::Function 6.x runtime should we be planning on adding the custom runtime or will 8 also be available without the additional container/image/build setup? Thanks!

[normj]

@jakenuts Using custom runtimes is a way to use .NET 8 in Lambda today. Eventually we will be releasing a new managed runtime for .NET 8. That means your AWS::Serverless::Function resources could target a dotnet8 runtime when it is released. Unfortunately I can't give a timeframe when the new managed runtime will be available other then it is coming.