Nanos, https://ops.city has had rust support for a while now as does OSv.

I'm involved with nanos/ops.

First time hearing about this, looks nice! but:

- is the Nano unikernel open source ? A quick (maybe too quick) google search tells me no.

- can you customize the component you want a la MirageOS, eg is it possible in the future to add a fail2ban to your app with a single command line ? same for filesystem and so on.

- is performance on par at least with other linux systems ?

- does it support rust ? not metal barebone rust, but rust with at least the std lib ?

Little late here but yes nanos is Apache and found at https://github.com/nanovms/nanos .

It also runs rust very well.