There's Alpine Linux too: http://www.alpinelinux.org/

I'll check out these distro's in the near future. I at least got a laugh out of what I saw on alpine's homepage:

"Simple. Small. Secure." right next to "ISO 298MB."

I know I'm getting old when people think a 298MB system is simple, small, or secure. Lol...

The Alpine Linux docker image is only a couple megabytes[0]. There are quite a few people (including myself) using it as a light-weight OS for their containers.

[0]: https://github.com/gliderlabs/docker-alpine

Now that is more like it!

for example, my redis container (samsaffron/redis) is 20mb, the official(tm) redis container is based on ubuntu is 100mb

There is also my own 'minifs' https://github.com/buserror/minifs ; it's targeted at embedded, but it works fine on x86s too. Haven't ported it to musl yet (mostly due to the fact that musl wasn't yet merged into crosstool-NG) but that's high on my list.

One thing minifs does is that it has a 'cross linker' took that jettisons every piece of code/library that is not actively linked by executable; also, instead of installing everyone's crap everywhere, I build the distro the other way around, and 'pick and chose' the bits that packages need until they work.

There's also Void Linux, which has musl and glibc versions of packages and offers both musl-based and glibc-based download images: http://www.voidlinux.eu/