wiki

If you like this, I'd also suggest reading on "Rumpkernels", which are also based on NetBSD. The core idea is (simplified): let's implement the kernel API in userspace so that we can take kernel-level components and run them as part of an application. Rumpkernels then allow, for example, taking all file system drivers in the kernel and running them in userspace without having to rewrite all of the file system tricky logic. Think of "mtools" if you ever used them, but by reusing existing FAT code. Or making it trivial to create disk images from userspace without having to have special kernel primitives nor root access. And also, they allow taking a userspace application and packaging it with the minimum set of drivers required to run "bare metal". Which is what the SSH example in the smol page brought to mind. See https://github.com/rumpke

Or NetBSD drivers via rump: https://github.com/rumpkernel/wiki

Just to point out for the first article (unikernels are undebuggable) - there's been a lot of work done in the past few years that effectively completely nullifies that argument: https://nanovms.com/blog/common-unikernel-debugging-myths-de... https://www.nccgroup.trust/us/about-us/newsroom-and-events/b... https://www.linux.com/blog/event/xen-summit/2017/9/uniprof-t... https://github.com/rumpkernel/wiki/wiki/Howto:-Debugging-Rum...

If you're into unikernels, rumpkernels[0] are the least-modification-required approach I've seen. Basically, if you compile your program with a minimally (as minimal as is possible) modified compiler, you get "rumprunnable" output. there's a list of popular packages built to run on rump kernels[1] (Rust is supported[2]). I haven't tried to use the toolchain yet, but it's pretty appealing to me. The biggest issue is that rumpkernels seem to not be in developed anymore. I can't tell if the entire is just off somewhere being productive with their rumpkernels and are happy or if no one is around at all. The Github organization[3]'s repos all seem to not have been changed in a while either. Outside of rumpkernels, Nabla containers[4] also look interesting to me. They're built on Solo5[5], but the only microkernels on there are currently Mirage

Thanks. The problem is, I actually have already read the appropriate sections of the FAQ & some rumpkernel.org pages, but I'm still confused. (I've written my original question out of frustration that things didn't become clear after all the reading.) I'm starting to think it may be best to dive in and try reading the "book" referenced in the FAQ (i.e. the Antti's PhD paper). Seems actually very approachable for a regular non-sciency engineer, from first looks. And/or maybe the "tutorial" I've found at https://github.com/rumpkernel/wiki/wiki/Tutorial:-Getting-st...

I just saw this so not sure if you'll actually see this response, but rump kernel doesn't imply Xen or such, that is just a common thing people want to do with them. It just means kernel drivers that can be used outside the kernel. Anykernel refers to a kernel that can be used that way with minimal differences and without modifying individual drivers. So rump kernel is "libkernel" and an anykernel is one way to get a rump kernel. There is a FAQ with more information at: https://github.com/rumpkernel/wiki/wiki/Info:-FAQ I'm pretty sure that Antti created these terms, so it is an authoritative definition :).

Have you come across Rumpkernel? I'd recommend looking at that since it can work with legacy code. There's a static-website tutorial that describes how to use Nginx as a unikernel. http://rumpkernel.org/ https://github.com/rumpkernel/wiki/wiki/Tutorial%3A-Serve-a-...

https://github.com/mato/rump-php http://rumpkernel.org/ https://github.com/rumpkernel/wiki/wiki/Info:-Community Ask on the mailing list/irc if you need help... its still under development so not completetly obvious yet ;)

There is more on github [1] and the wiki [2] including videos and articles [3] [1] https://github.com/rumpkernel [2] https://github.com/rumpkernel/wiki [3] https://github.com/rumpkernel/wiki/wiki/Info%3A-Publications...