> what would be better for my career and what branch do you think has a better future?
Based on your limited description, I think both would be fine your career, and both branches will do well enough in the near future.
Questions to ask yourself:
* how much freedom do the companies offer you? How many of your own ideas can you bring in?
* are the good programmers how can mentor you at each company?
* how much does the choice of tooling affect you? That what you'll work with all the time. How fast is it going to change?
* how much does the business branch actually affect your work? If you're doing frontend development for an infosec company, you're not doing intrusion detection or the like; if you do frontend development for an airline, you won't do flight or luggage routing. My point is that it's not a given that the branch will actually influence your work very much. (It might still be, though).
* How many people will use the software you write? How much does that matter to you?
* Are there any ethical differences? Do you support the companies' values and methods?