Pros
The mission-critical systems developed in ION are complex and technologically challenging, though with big technological debt. Salary is competitive if you become to be one of those few remaining experts who had not left yet and now you are critical person that keeps the particular product alive. Anyone below that is basicaly without bonuses and pay raise.
Cons
I'm disgusted from ION as many other employees. The company is in constant loop of aquisitions, draining the aquired companies from resources, letting most senior people to leave, making many others redundant. The last time it happened to Fidessa but many others before. Many teams are on the very edge of ability to maintain their products. Customers don't know that software that serves their multi-bilion businesses is sometimes kept alive by the last 2-3 developers and units of persons in operations. ION constantly tries (and mostly fails) to somehow integrate the software solutions they acquired. There is a big known issue of non-transparency and lack of communication in the company. This is crazy environment where most employees openly blame and contempt CEO Andrea Pignataro. Just google for Financial Times articles that accurately describe how and where he leads the company by squeezing, making debts and how he buys islands and real estate developer projects. Totally centralized and flat mgmt model. Example: Every single person to be hired, including any junior developer in whichever office around the globe, needs to be approved by CEO (!!!). This is the way how he effectively blocks any hiring. The interviews are passed at lower levels and the file gets blocked at his desk without any explanation for weeks and months, until the candidate looses their interest. Most dev centers are in state of effective hiring shutdown for years now (so the covid period is not the cause).