Hi @anyx, highly respect your project, but personally disagree with this notion/philosophy.
In my opinion, close-sourcing code is not the correct solution to a problem of malicious use. Firstly, it doesn't actually work: eventually malicious code will be written and open-sourced. Secondly, the system needs to be exposed to malicious code in order to develop strategies for counteracting it.
There may be other motivations, such as economic and anti-competitive ones, to close-source your code. If that's the case, I would suggest to an intellectual property developer to state them up front.
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