Try it with the LING Erlang-on-Xen unikernel and see for yourself if it's not debugabble.
Looks like they've got a solution for dubugging: https://twitter.com/erlang_on_xen/status/641628659657371648
Looks like they've got a solution for dubugging: https://twitter.com/erlang_on_xen/status/641628659657371648
But if we're comparing unikernel-VMs to containers, my guess is that most users are after the "take my $LANG binary and concatenate it with half a Linux kernel"-workflow. And for that general case, most standard tools are off the table.