Pros
Some interesting projects. Free tea and coffee. Cheap restaurant. Relocation assistance provided by externals on a commission basis. German language lessons.
Cons
Toxic bureaucratic environment in most IT departments, each team fighting the other. No handovers are usual when stuff or externals leave. Processes are very slow, i.e. a creation of a linux user account may take weeks. Monthly net salary of less than 2000 € for an experienced programmer in Frankfurt am Main. Some programmers have to work over 10 hours and even at home. Too many analysts, architects and managers for teams with a sole developer. Some IT tools and hardware used are too old, malfunctioning and obsolete. Their austerity motto is: "cut all sources of cost". Low order employees. especially security personnel on the ground floor, can hardly speak any English. English is rarely used, the business, meetings and project documentation language is German, no matter what promises are given orally during the interview, in order to persuade you to join DB. What counts is what is written on paper and signed. Insults and personal attacks from superiors in front of other people on a daily basis. Maltreatment, harassment, bullying and racist remarks are quite common. Non German speaking foreigners are considered more or less as potential industrial spies. In a word, it is like the army.