Here's how I build my own images. More details are in the repo, feel free to re-use https://gitlab.com/olof-nord/selfhosted/-/blob/main/images/Makefile
Only unstable, right?
I should say as well, postgres, mariadb and memcached all support riscv, you just got to build it yourself. I have found the riscv64 ubuntu docker images useful as well to use as a base - for example the riscv64/ubuntu one.
I do! Since a while I selfhost with my risc-v Unmatched board. There are prebuilt Ubuntu Server images available. Its mainly for software which you have the source code for, and are willing to build from source. I've made use of docker buildx for cross cmpilation a fair bit as well. Go and Rust has good support. A good start can be to check out the riscv-bringup repo from carlosedp. Its definitely early days though, you need to be pretty motivated. Debian support is scheduled for next year AFAIK.
So, what do I actually use it for? nginx + tailscale so far
I would also say this. Njalla is good
Because borrowing from the IMF is completely without any strings attached?
My first thought. Where is this?
Tailscale maybe? They have a mode where you can configure a site to site links, you could route the docker networks. https://tailscale.com/kb/1019/subnets
Just in case - there are also good linux desktop applications - check out Authenticator on flathub for example.
Jerboa. It ticks all the boxes, is updated, and looks good
Tbh, that's the only platform where it is needed?
One idea is perhaps to have more than one device? A tablet at home could be used in some scenarios, the rooted phone for some others. Maybe you have an old device laying around?