[debevv]

The concept of a system-wide hierarchical key-value store is actually very useful is some environments. I had to develop one some time ago [1] for an embedded system, since is super useful to have a single point of truth/configuration/state, if every application agrees on using it (which is the case in such systems were every application is known in advance and developed in house)

[1] https://github.com/debevv/camellia

[rwmj]

Xen (the hypervisor) had a thing called XenStore which was a system-wide key-value store with triggers: https://wiki.xenproject.org/wiki/XenStore