Pros
The only pro is that you earn a paycheck, which of course is not unique to Fiserv. This is a great company for people of average or below-average talent who fear challenges and change, and simply wish to live out the remaining 10-20 years of their careers until retirement. Just hope you don't get laid off before then (spoiler alert: you probably will, especially with the downsizing Fiserv is planning following the big First Data merger from 2019).
Cons
Let me preface this by saying that I came to Fiserv unwillingly as part of the acquisition of First Data. I also originally came to First Data the same way, unwillingly as part of the acquisition of another smaller company, which I won't name in order to prevent retaliation from Fiserv's management (we were a small and focused team of talented engineers and other professionals who took pride in our work and brought in tons of revenue relative to the small team that we had). I hated First Data before, and I hate Fiserv too - so I'm not on either company's side. With that background out of the way, believe me when I say that Fiserv is painfully mediocre. From the talent of the people who work for "Original Fiserv" (as their brainwashed veteran employees like to call it), to the way they compensate their employees - regardless of their contributions or level of talent - this company is nothing special. The only place where they're not average is in the benefits package, which is below average for the industry and is not particularly competitive. They shun working from home as though it is some kind of detriment to productivity (they frequently remind us of the importance of "seeing people's eyeballs" in order to be truly productive, which of course is laughable), and they treat their employees as numbers instead of people. I'd be able to just accept this as typical corporate nonsense, but then they try to pretend like you should be proud to work here - spouting off how badly they want to be the "best fintech on the planet!!!", or making laughable and cringeworthy attempts to seem "hip" by promoting the Twitter hashtag #FISVProud. So we should be proud? Proud of what, exactly? This place is so mediocre it hurts. There's a reason why the average employee age at Fiserv is probably around 50 or so - this company offers nothing competitive to attract new talent, and simply relies on retaining "lifers" who have been with Fiserv for the past 20 or so years, and are afraid of change or tackling new challenges. This company depends upon the complacency of their jaded, aging employee population to just accept what they are handed down from above, and not question it or wonder if they could be doing better for themselves working somewhere else. I could go on and reference other Office Space-style things that I have seen so far working for Fiserv, but I think you get my point. If you are a talented software engineer looking to join this company, please believe me when I say you should look elsewhere. This company is not for talented, driven people or those who enjoy challenging work. Fiserv will not value you as a contributor, regardless of your level of talent, and will find any way they can to give you as little compensation as possible. I truly believe that upper management at Fiserv does not actually want highly talented professionals to work here, because they're not willing to pay the salaries that are required to hire and retain such top contributors. This company was made for mediocre people, so if you see yourself as more than that, do yourself a favor and do not apply here. You're worth more than this company is willing to give you. However, if you are just looking for a place to simply exist and make a simple paycheck, then I think you'll enjoy this place quite a bit. Who knows, maybe you'll even be brainwashed enough to post a Tweet celebrating your employment here with the hashtag #FISVProud! (I'm rolling my eyes as hard as I can typing this.)