I heard on the grapevine once that Goldman Sachs have a proprietary distributed database built in Erlang.

Can neither substantiate nor deny but did make me wonder about all the hidden proprietary tech out in the world...

> heard on the grapevine once that Goldman Sachs have a proprietary distributed database built in Erlang

From the article, third paragraph:

Goldman Sachs built its messaging system using RabbitMQ, which runs on Erlang, in 2018. Jonathan Skrzypek (who now works for Coinbase) was running the messaging engineering team at Goldman at the time. The system had to be fault-free because the messages it was transmitting could "worth a couple million dollars," said Skrzypek. RabbitMQ was chosen because of its resilience and "reliable delivery, guaranteed delivery."

A comment to the posted-article, from "Frellus", who identifies as ex-Goldman, suggests RabbitMQ might not have been used so extensively:

Ex-Goldman person here. To the best of my knowledge, RabbitMQ was used in spots but not where reliability was critical. Instead the main message brokers were IBM MQ and TIBCO. RabbitMQ would certainly lose messages in the event of a crash, and I'm not sure it would have been used for the main message bus given the rate of events. Additionally, Erlang was used for SecDB queries quite heavily. This was the bread-and-butter of the firm (https://github.com/saleyn/secdb)