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Licensing conundrum

  • Hello!

    I'm fairly new to the programming community, and have a -hopefully simple to answer- question.

    I'm developing a system at my workplace as a kind of first real project. I'm absolutely a novice. Just want to make that clear.
    I've written a good chunk of code in C++ that performs a very specific task for the business. It took me quite some time, but it's working well now, and after watching some tutorial videos on Youtube, I'm SUPER excited to build my first GUI for this program in Qt.

    This brings me to my predicament.

    My boss told me that his intent is to, one day in the future, patent the hardware modules I built (the ones that are feeding the software I built) and somehow sell the system as a package to other businesses. He said we would share the patent (I think that's a good thing?)

    What bothers me quite a bit is the whole licensing bit.
    Qt seems extraordinarily fun to use. My trial ends in a couple weeks and I haven't even tried using it due to my apprehension.

    I have however, attempted to use many other GUI libraries for C++, and after days to weeks of trying, I can't even get a basic window with "Hello world" to display in any of them.

    This is what attracts me to Qt: the widespread tutorial videos available and the easy-to-use and modern looking interface.
    Just makes me sad that I might not be able to use it without paying $350/month (which is waaaaaaaay out of any of our budgets).

  • Hi and welcome,

    As long as you're not modifying Qt sources and you're using dynamic linking, I think you can take advantage of the LGPL licence, which allows to use Qt in a commercial and non-open source software. There some requirements, but nothing really overwhelming I would say. If you look over the forums, you'll find several discussions on the subject.

  • Hi @Kelevra

    You could contact sales at The Qt Company and explain your situation and ask for them to extend the trial period. To me it sounds like you started your trial period a bit too early.

    Also what @JohanSolo says, as long as you have nothing released to anyone and you don't use the parts of Qt that are under the commercial license, you technically could use the open source version.
    However once you do start looking at selling your product (really productising the thing), we here at The Qt Company really would like for you to get the commercial license.

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