@startuml

state "current state" as current
current : NixOS 22.11 w/o flakes

state "next state" as next
next : NixOS 22.11 w/ flakes

state "future state" as future
future : NixOS 23.05 w/ flakes

state "initial state" as initial
initial : "Ubuntu"

initial -r-> next : implemented &\ntested @ hetzner\nTODO: digital-ocean
current --> next : not tested\n(2023-11-30)
next --> future

note right of next
updated
application
needed
end note

next -u[#red,dashed]-> current : full rollback\n<color:red><b>not possible\n(hard to implement)
future --> next : full rollback\npossible

@enduml