In my not too long experience as a software developer, I have encountered with people (usually my bosses) using software which is very much not suitable for the scale of the project I was working on. This, combined with the fact that they are usually expert in areas other than IT, lead to wasted working hours and frustration numerous times. Despite me pointing this out, nothing has changed, and I was still expected to use that technology.
(Concrete example: linguistics-based project involving loads of data. Boss with linguistics background uses Microsoft Excel. It didn't always work as expected & I found this out, and I suspect there were cases where it didn't work as expected without me discovering it. I was hired as a Python developer. Now I read that some other people are also not able to use that product well, while the stakes are high (here, here, here) - now, partly owing to their mishap, COVID cases are also skyrocketing. Also happened in a genetic study & in one of Scotland's elections.)
I am likely to work for a company where I can dictate the conditions at some point in the future.
Is it professional, or common, to write a contract which includes that I will under no circumstances will use a certain technology (in my own case, Excel), because in my past experience, it is a source of frustration and dangerous unexpected behaviours?
If yes, should I include a reason, or just state the fact?
To address the issue that some pointed out - that I am not in a position to dictate the conditions: That is probably true in most cases, however, I have reasons to think that it is not the case now. I worked on projects which were very much in need of manpower, and I got to dictate many other aspects of the conditions, such as number of hours worked in a week & my salary. I got away with not having fixed working hours, as long as I have done the job, it was fine. Not as a result of my own excellence or anything like that, but due to my fortunate schooling background in my past, I had the opportunity to study in very prestigious universities. I do not think that this makes me a significantly better developer, but it does seem to boost my CV among the eyes of the employers. And if I did not like the company, I could always walked away, because I had other options. These factors combined, I have had big leverage in the conditions.