[TheDong]

Certificate transparency fits right on top of postgres, see crt.sh https://github.com/crtsh

Or on top of LevelDB or sqlite if you look at google's implementation of it:

https://github.com/google/certificate-transparency#software-...

The source of truth for certificates is certificate authorities. Certificate authorities by definition must trust the claims other authorities make about what they issued. There's no need for "proof of work". There's not even any distrust.

There's a need for an audit log, an append-only database, replication, and distribution of data.

There is no need for solving the generals problem, for hashing, for confirmations, for any of the blockchain really.