"Blockchain", not bitcoin, and "Blockchain" is quite literally a specific application of Merkle Trees and Merkle Proofs, and they've been used almost exactly like this in payments clearing & settlement + dispute systems for tranlog coherency checks and resolution for a long time.

"Reactive", as in http://www.reactivemanifesto.org/, and it's manifestations in various Akka projects like http://www.reactive-streams.org/. Reading the "manifesto" reads like somebody going to really, really extensive lengths to talk about Erlang without actually saying "Erlang" and that's been around publicly, along with its runtime semantics, since 1998.