Really it's more that the firecracker supports ARMv8 64bit, and the author tested it on a raspberry pi (as well as a HiKey970 board) but anyway.

This is really cool we'll likely see custom arm servers running in AWS as a way to reduce cost / improve scalability.

They already have ARM instances; https://aws.amazon.com/ec2/instance-types/a1/

Other providers like scaleway has been offering ARM servers for a while now[1].

[1]:https://www.scaleway.com/en/virtual-instances/arm-instances/

* arm instances for Lambda workloads. Do you know if you can choose your architecture when deploying a function? I'd be curious to see the performance of node on x86 vs aarch64

Is it just me or are those ARM instances rather expensive compared to other EC2 options?

It's the price for a not-very-specific vcpu. Your performance could be better on the A family, more than offsetting the price difference. Of you're really considering the choice - you should test your workload on both. Or maybe they save you time in a different way - for example you save time not having to run a virtualised linker after cross-compiling.

It's the first generation of the hardware. I'd imagine the costs will start to come down over time as they ramp up the supply chains.

No, previously there were issues with the virtual interrupt controller, and it was running on Arm64 servers but not the pi4.

have tried on this prebuild 64bit ubuntu kernel with kvm enabled

https://github.com/TheRemote/Ubuntu-Server-raspi4-unofficial

I don't suppose anyone could direct me to a resource outlining how to develop targeting this environment.