Pros: Good training program for entry-level people. Quite a few smart people around. Great offices to work in: very attractive, good location, communal kitchen, lecture theatres, etc. The office in general feels quite busy and bustling. Lots of perks like free theatre/exhibition tickets, events, etc. Good amount of responsibility from early on. Good pay. Good name to have on the CV.

Cons: Lots of the codebase is pretty antiquated – Fortran code, old 1000-line C functions from the 1980s, etc. Lots of proprietary stuff you have to learn that isn't transferable, so you run the risk of getting a bit institutionalized. Also, Bloomberg often unnecessarily has its own little version of something (file I/O libraries, etc.). Senior management have their heads in the clouds and are fairly political. Many have been there since the dawn of time and have an outdated view of how the company works. They will push through initiatives that they have 'sold' to their superiors, even if they just don't make sense at ground level. One of those companies (and there are many) that sell themselves to applicants as having a 'flat' structure, when what this actually means is that hardly anyone ever gets moved up. There is also lots of bureaucracy and a culture of micromanagement – every working hour must be ticketed, accounted for, etc.

Pros: Bloomberg has its head screwed on internally and treats the development department as a core department, not a cost center. Teams are quite regimented, but there is opportunity for internal transfers. Instead of a Christmas party, Bloomberg holds an enormous summer party in the park, families invited, which I found a nice way of handling things. The grad training program is excellent, if extremely hard work.

Cons: A serious case of "Not Invented Here"; you will often be working with old technologies or internal stacks. At least they are generally of decent quality. The London office felt a bit marginalized by New York. Don't expect to get financial experience. Financial news is not the same as finance, and developers are well isolated from business concerns anyway.

Pros: People are first-class, very bright, and motivated. Bloomberg has hired experts in many different aspects of technology, finance, and news in one place. Flexible work style accommodated.

Cons: - Still slow to adapt to new technologies. - Very focused on the terminal product.