I can understand your hesitancy, but I think in practice I strongly disagree. A big part of why I like Ada so much is the fact it lets me hold such a strong me

I can understand your hesitancy, but I think in practice I strongly disagree. A big part of why I like Ada so much is the fact it lets me hold such a strong mental model of the program. I can specify quite a bit about how it should all work, and the compiler holds me to it. Most or all of that sort of information is tied up in the .ads file. If I want to refer to the model, I can check the .ads file, even if my project doesn't compile yet. Everything I need to know is there, from the very first line of code. Most importantly, if I'm working in the .ads file, I'm changing the model. Changes here are Important. If I unknowingly make a change here, I've lost my understanding of the model. I really don't want that to be possible. Meanwhile the .adb is more the implementation. If I'm changing the .adb, I'm just altering the details, but the overall model stays the same. Maybe what I'm doing in the .adb tells me I really do need to change the .ads because the model has a problem, but that doesn't mean I should just go make the easiest little change to the model that makes the .adb work. Frankly, I think that extra little bit of friction in having two files that need to be in sync makes it easier to write better programs. Something as huge as changing the model should have something that helps cue me in that I'm doing something Big.