appcypher

microsandbox is open-source and runs on linux, macos and windows: https://github.com/superradcompany/microsandbox/

it's been mentioned on this thread already, we think https://github.com/superradcompany/microsandbox/ is the closest OSS to it and we have a great DX and improving.

that's the tldr. we used fuse and we learnt we shouldn't for a sandbox filesystem

interested. is the split for dedup, parallel pulls, or lazy loading specific files? maybe all.

we've played with some chunking ideas on our end but haven't landed on a format. drop a link when it's out.

fair point. that's the title we used on our X article and i copy-pasted. updated the article's actual title.

What do you mean?

Not sure what that entails. You can try and I can help along the way

Wow. Just seeing this. I've not done proper benchmarking yet but rn we are lagging behind in file I/O for the OverlayFS impl

They are similar. We use libkrun under the hood. Firecracker team seems not to be interested in a macOS implementation

Katacontainers is an interesting project. Microsandbox is a more opinionated project with a UX that focuses on getting up and running with microVMs quickly. I want this experience for Linux, macOS and Windows users.

More importantly is making sandboxing really accessible to AI devs with `msb server`.

No they are not.

If by embeddable, you mean having the vm run in the same process, then no. The vm aborts its process when it's done so it has to run as separate process.

Will fix the docs

We support just Docker hub for now. Let me know if you want any other OCI-compatible registry.

PS: microsandbox will likely have its own OCI registry in the future

They are Linux VMs and you can host any executable that can work on that. The python/node environment you see is part of what makes the SDK work. Really, it's very similar to Docker in use.

Your statement initially went over my head. Sorry lol. You can always download the installer script and audit yourself. I will set up proper distribution later.

Right. You can skip the `with` context manager and call start and stop yourself.

There is an example of that here:

https://github.com/microsandbox/microsandbox/blob/0c13fc27ab...

It will be maintained as I will be using it for some other product. And it will be audited in the future but it still early days.

> can you share some thoughts on how you compare or future direction?

Microsandbox does not offer a cloud solution. It is self-hosted, designed to do what E2B does, to make it easier working with microVM-based sandboxes on your local machine whether that is Linux, macOS or Windows (planned) and to seamlessly transition to prod.

> Do you also use Firecracker under the hood?

It uses libkrun.

We want microsandbox to be usable for everything you can with Docker.

That said, hosting microVMs require dedicated hardware or VMs with nested virt support. Containers don’t have that problem.

They can. I need to improve the doc. Working on that right now

Yeah. I need to fix that in the docs!

> 1. each one should have it's own network config, eg so i can use wireguard or a vpn

This is possible right now but the networking is not where I want it to be yet. It uses libkrun's default TSI impl; performant and simplifies setup but can be inflexible. I plan to implement an alternative user-space networking stack soon.

> 2. gui pass-through to the host, eg wayland, for trusted tools, eg firefox, zoom or citrix

We don't have GUI passthrough. VNC?

> 3. needs to be lightweight. eg gnome-boxes is dead simple to setup and run and it works, but the resource usage was noticeably higher than native

It is lightweight in the sense that it is not a full vm

> 4. optional - more security is better (ie, i might run semi-untrusted software in one of them, eg from a github repo or npm), but i'm not expecting miracles and accept that escape is possible

The security guarantees are similar to what typical VMs support. It is hardware-virtualized so I would say you should be fine.

> 5. optional - sharing disk with the host via COW would be nice, so i'd only need to install the env-specific packages, not the full OS

Yeah. It uses virtio-fs and has overlayfs on top of that for COW.

You are right. We leverage libkrun. Libkrun uses virtio-mmio transport for block, vsock and virtio-fs to keep overhead minimal so we basically depend on any perf improvement made upstream.

Firecracker is no different btw and E2B uses that for agentic AI workloads. Anyway, I don't have any major plan except fix some issues with the filesystem rn.

> Would that be a good use case for this?

That is an ideal use case

> Are there better alternatives?

Created microsandbox because I didn't find any

The other SDKs are generated hello-worlds at the moment. I will get to them one by one, but I welcome and appreciate any contributions to them.

Microsandbox is for people that would like to maintain their own infra. I'm not going to stop trying to make it better to self-host.

> What is the most minimal microvm for WASM / WASI,

By setting up an image with wasmtime for example.

> and what are the advantages to running WASM workloads with firecracker or microsandbox?

I can think of stronger isolation or when you have legacy stuff you need to run alongside.

Yes! With the `scope` property.

https://github.com/microsandbox/microsandbox/blob/0c13fc27ab...

It uses libkrun which uses Hypervisor.framework on macOS.