Show HN: Smol machines – subsecond coldstart, portable virtual machines

Hello, I'm building a replacement for docker containers with a virtual machine with the ergonomics of containers + subsecond start times.

I worked in AWS previously in the container space + with firecracker. I realized the container is an unnecessary layer that slowed things down + firecracker was a technology designed for AWS org structure + usecase.

So I ended up building a hybrid taking the best of containers with the best of firecracker.

Let me know your thoughts, thanks!

The feature that lets you create self-contained binaries seems like a potentially simpler way to package JVM apps than GraalVM Native.

Probably a lot of other neat usecases for this, too

  smolvm pack create --image python:3.12-alpine -o ./python312
  ./python312 run -- python3 --version
  # Python 3.12.x — isolated, no pyenv/venv/conda needed

Can .smolmachine be digitally signed and self authenticate when run? Similar to https://docs.sylabs.io/guides/main/user-guide/signNverify.ht...

I see the alpine and python:3.12-alpine images in your cli docs. Where does these come from?is it from a docker like registry or are these built in? Can I create my own images? Or this this purely done with the smolfile? Is there a Ubuntu image available?

Looks really nice btw. Hot resize mem/cpu would be nice. This could become a nice tech for a one-backend-per-customer infra orchestrator then.

What are you actually doing on top of libkrun? Providing really small machine images that boot quickly? If I run the smolvm run --image alpine example, what is "alpine?" Where is that image coming from? Does this have some built-in default registry of machine images it pulls from? Does it need an Internet connection that allows outbound access to wherever this registry runs? Is it one of a default set of pre-built images that comes with the software itself and is stored on my own filesystem? Where are the builds for these images? Where do these machine images end up? ~/.local/share/smolvm/?

Great job with the comparison table. Immediately I was like “neat sounds like firecracker” then saw your table to see where it was similar and different. Easy!

Nice job! This looks really cool

Basically any open source project nowadays run their software stack in containers often requiring docker compose. Unfortunatley Smol machines do not support Docker inside the microvms and they also do not support nested VMs for things that use Vagrant. I think this is a big drawback.

Could it be made even faster using some of the ideas from https://github.com/zerobootdev/zeroboot ?