Having worked at Bloomberg I really wish there was more content published about how it's implemented because it pretty astonishing in both good and bad ways. For one thing the codebase is ancient there are still some Fortran bits that in use today. However the more modern code is in C/C++ and designed heavily with latency in mind. In particular the feeds are designed to be extremely fast with a few custom built high performance databases built to serve this [0].
The bit that really amazed me was the way the front end is implemented. The front-end is fully rendered server side (meaning every click requires a full round trip to Bloombergs servers) in Javascript using spidermonkey. This caused a lot of difficulties since any real time elements needed to be rendered in a totally different way. As well the version of Javascript was restricted from using things like timers or callbacks since that could make rendering stall. In some ways it's impressive that they were doing server side Javascript at least 5 years before nodeJS but whole approach seems like a byproduct of age of mainframes.
The bit that really amazed me was the way the front end is implemented. The front-end is fully rendered server side (meaning every click requires a full round trip to Bloombergs servers) in Javascript using spidermonkey. This caused a lot of difficulties since any real time elements needed to be rendered in a totally different way. As well the version of Javascript was restricted from using things like timers or callbacks since that could make rendering stall. In some ways it's impressive that they were doing server side Javascript at least 5 years before nodeJS but whole approach seems like a byproduct of age of mainframes.
[0] https://bloomberg.github.io/comdb2/overview_home.html