Desk Ergonomics

Has anyone been able to figure out a good computer chair situation for desk work? I find that it has just been ruinous to my back to sit at the computer, but I don't have a lot of options due to the kind of work I do. In addition to my back being hunched over, I find that my abdomen gets compressed a lot and it negatively affects digestion.

I do go to the gym, do yoga and stretch regularly, but I feel like there has to be a better way to do desk work? No, I do no wanting a standing desk because I don't like standing while I work. Has to be a chair.

TIA!!