I'm only 3.5 years post college, my advice might not be the most sage. I'd take whichever you think you'll enjoy most in the moment, and it sounds like the contract. You should ask them about possibilities for "contract to hire", though. A lot of places like to do that anyway. From my experience, the contract work will look better on a resume and help a lot more for finding a new job in 1-5 years, and your skills won't stagnate. I took some more stable jobs in my own career, but that's mostly because I think of coding strictly as a job and less of a hobby, and I'm happier with a stable paycheck, but a less challenging, engaging, and exciting job.

But if you're in a position where it is very important for you to have 100% of your income and a guarantee of work in 7 months, maybe take the more stable one. Like if you have kids or family that you're supporting. But if you're thrifty and good at interviewing (which it sounds like you are), sometimes contracts can actually be better financially in the long run, just more work. It really depends on the jobs and your attitudes towards them. But nothing is ever set in stone for your career path, as long as you can learn new things and show them off. If you decide on the financial group but are still worried, I'd recommend just having a side project your working on in a personal, non-work-affiliated github and just keep up on trends with that.