Adding mongo's API to a postgres db with a few functions because why not.

"The Maginot Line was a huge fortress that ran the length
of the Franco-German border and was constructed at great
expense between World War I and World War II. It
successfully kept the German army from directly crossing
the border between France and Germany. It was quickly
bypassed by the Germans in 1940 who invaded through
Belgium"

Paxos is a family of protocols for solving consensus in a network of unreliable processors. Consensus is the process of agreeing on one result among a group of participants. This problem becomes difficult when the participants or their communication medium may experience failures.

Facebook also has an extensive MySQL infrastructure, but they found performance suffered as data set and indexes grew larger. And they could have built their own, but they chose HBase.

Talks a bit about Liquibase.

This looks fantastic.

Anecdotes that reinforce not having a shared DB for developers.