Hacker News Reader

Comment by kortex | Hacker News Reader

Obviously the "Oranges: the new apples?" title is off-base; k8s is fundamentally a control loop engine, Wasm is a runtime.

What I want to know is, is there anything out there like kubernetes but stripped down to just the control loop engine part? Like a glorified IFTTT but without all the overhead and baked-in assumptions of k8s. Some kind of daemon/library where I can write an arbitrary controller which reads a spec, queries some state, and has actions to push the system toward the desired state.

The actual I/O is just writing an API and could basically just be a CRUD. What I'm looking for is the state management engine; that is tricky.

View on HN

That's what Terraform pretty much is. All it does is manage a graph of dependencies/resources and then relies on a provider, which implements the CRUD.

Not super familiar with Hashicorp's other product Nomad but I'd think it have a similar approach, but more of a continuous lifecycle check?

> k8s is fundamentally a control loop engine, Wasm is a runtime

Thank you for this comment. I was scratching my head wondering what developments I had missed on the wasm side of things that would replace k8s.

So essentially wasm could replace or augment the CRI in k8s eventually. That sounds great if it can be properly integrated with the rest of the platform like Ingresses, PSPs, etc.

There are already people working on WASM as a CRI runtime in k8s: https://cloudblogs.microsoft.com/opensource/2020/04/07/annou...

If it's process control specifically then systemd or a lightweight process manager like s6, supervisord, foreman, etc. are a good option. You can do things bare metal or just run containers as processes. systemd services + nspawn is pretty close to k8s container control for a single host

For the infra side of things you have hashicorp terraform, which will manage state of your infra and can also manage the state of your workloads.

For the workload side of things you have hashicorp nomad. Which is basically a stripped down version of k8s.

I don't know if it's Terraform or our implementation but I've not been particularly impressed by Terraform's error state recovery functionality.

If something takes to long to pass a health check you often do not end up in State A or State B. There is a lot of surface area for undefined behavior.

Not really. Nomad is closer, and Mesos (the old one) is closer still.

I wrote my own as a rust library, and I'm in the progress of further breaking it apart. Might get a prototype finished this weekend and if so, I'll share it here.

Mesos, but it seemed like Kubernetes ate it’s lunch since most use cases are handled with a single controller.

Reply on news.ycombinator.com