I've been using SlicerVM extensively - which is Firecracker MicroVMs for the regular person (and for the irregular with their platform offering) - to run local 'edge' style workloads locally and securly. Agents, local dev CI, etc. It slotted in and replaced my proxmox vm orchestrator, and now I have secure and and fast vms on my laptop wherever I go. It also supports dockerfile style builds if you're wanting a security upgrade from containers (which, you should if you're using agents).
Honestly, while I see firecracker replacing docker on the horizon I don't see firecracker replacing v8 isolates for most edge function execution. Firstly, this article's scenario is a bit unusual in that they were using someone else's isolates - so adding on a few hops; secondly isolates running JS/TS can be statically analyzed quite well, and at scale looking historically for issues and exploits, in many edge compute scenarios this is quite desirable. MicroVMs can have an awful lot more flexibility so to get the same benefit you have to really lock down what is available - the trade-offs for mid-size companies seems to benefit isolates. Obviously netlify is more than big enough and relies heavily on this that it leans in their favour.
> When the MicroVM boots up and the JavaScript server begins to listen on a port, we take a snapshot of the MicroVM. [...] we start a new MicroVM from that snapshot.
That sounds scary, since forked RNG states can lead to catastrophic failures in UUID generators or cryptography.
I'm having trouble understanding/believing this, given that Cloudflare Workers are also v8 isolates and run vastly faster than the 25-40ms that netlify says their isolates took...
from the article: "With our old infrastructure it went out over the internet, ran the edge function, and came back to us to pass on. With the new compute platform, the request is forwarded to a compute node within our network."
As far as I know, Cloudflare Workers have always executed within Cloudflare's network, not gone out to the internet and executed elsewhere (which I read as being in a hyperscaler cloud).
The next time you want to curse AWS, remember they gave us Firecracker, one of the best microvm technologies out there, and the basis of at least a few non-AWS products out there (this one being the newest entry to the list).
This is highly interesting considering AWS invented the MicroVMs for lambda, yet node on lambda is dog slow (both in latency and throughput). I can traumadump on request. I bet they could use some of this tech especially since their use cases are often not too dissimilar (auth validation, rule checking etc)
v8 isolates aren't actually a great sandbox and I would not trust them implicitly in the AI era. This is probably why they wrap them in an additional sandbox.
Without commenting on v8 isolates specifically, this doesn't necessarily hold in any isolation situation; many customers are running code on behalf of their customers, which are often submitting jobs on behalf of theirs, and so on. Isolation breaches within a platform customer can result in significant cross-user data breaches.
Not only are they shared kernel... They're shared process, shared address space, shared memory pool and allocator... In fact, there is very little isolated about them at all.
I bet there are a million ways to cause side channels allowing learning about other code or data on the same machine, and just one V8 bug (of which there have historically been thousands) let's you take over or modify code in another isolate.
This is technical content, written for a technical audience, being shared on HN. In that context, it's not particularly esoteric. If "5x faster Edge Functions" means nothing to you, that's a good signal that you can just skip it without FOMO. If you're familiar with the concept but not Firecracker (a popular microVM) specifically, the expectation is that you'll use search engines and/or LLMs to get up to speed.
Honestly, while I see firecracker replacing docker on the horizon I don't see firecracker replacing v8 isolates for most edge function execution. Firstly, this article's scenario is a bit unusual in that they were using someone else's isolates - so adding on a few hops; secondly isolates running JS/TS can be statically analyzed quite well, and at scale looking historically for issues and exploits, in many edge compute scenarios this is quite desirable. MicroVMs can have an awful lot more flexibility so to get the same benefit you have to really lock down what is available - the trade-offs for mid-size companies seems to benefit isolates. Obviously netlify is more than big enough and relies heavily on this that it leans in their favour.
We also did a couple of technical write ups if you're interested:
- https://unikraft.com/blog/netlify-edge-functions
- https://unikraft.com/customer-stories/edge-functions-netlify
That sounds scary, since forked RNG states can lead to catastrophic failures in UUID generators or cryptography.
As far as I know, Cloudflare Workers have always executed within Cloudflare's network, not gone out to the internet and executed elsewhere (which I read as being in a hyperscaler cloud).
The isolates were not being run at the edge.
They were outsourcing to another company so there's plenty of room for overhead to creep in.
while microvm's are separate kernel + hardware virtualization through hypervisor guarantees
I wouldn't call it bad either, just different tools for different things
I bet there are a million ways to cause side channels allowing learning about other code or data on the same machine, and just one V8 bug (of which there have historically been thousands) let's you take over or modify code in another isolate.