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I've recently switched careers from academia to software. At the present, I am wrapping up development on a my first commercial/non-academic project, a time sheet and invoicing system. The experience was very useful in terms of learning, but not positive. I doubt any reference I might get from the project manager would be useful for further work.
I know the experience will come up in job interviews and I don't want to be negative, despite being irate about some of the things that occurred. I am capable of acknowledging my own faults in the situation (the ones I know about, of course), and can also discuss, in a general way, what should have been done differently. I'd like to hope I can prevent, and will certainly try my hardest to prevent, myself from repeating the same errors. I know many developers have negative development experiences, and that I'm taking this a bit too personally. I know I had a hand in many of the problems, and that I have a lot to learn about developing away from academia. I know that there are many things I should have done differently. I know the experience is mostly in the past and cannot be changed, only learned from.
Despite this, I become visibly upset when the project comes up, even when I opt to say nothing. I'm aware this reaction will be perceived poorly during interviews and do not wish to give the impression that I have made a habit of reactions like this or that I cannot use this as a learning experience. Neither are true.
How should I discuss this experience during interviews?
I should be very clear about this: my emotional state is my problem. If I have given any other impression, I apologize. I included my emotional state to contextualize the situation. I also included it because the answers I get may be of use to someone else in a similar situation.
I should also be clear that the situational particulars don't matter--whether or not anyone else would feel the same way given the circumstances, I still need to go to interviews and discuss this in a professional, constructive fashion.