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My company is going to hire an external developer to create some new modules and fix some bugs in our PHP software.
We have never hired an external developer by the hour before. How can we protect the source code? We are not comfortable giving out source code and were thinking that everything remained under a surveillance enabled VPN which external developer would log in to.
Has anyone solved this problem before? If so, how?
Edit: We want the developer to see/modify the code but under surveillance and on our machine remotely. Does anybody have a similar setup?
Edit 2: NDA is just a formality. IMO, even people who are in favor of NDAs know that it'll do nothing to protect their property.
Edit 3: Let me clarify that we aren't worried about the developer copying an algorithm or a solution from the code. Code is coming out of his brain, so naturally he is the creator and he can create that again. But our code is built over several years with tens of developers working on it. Let's say I hire an incompetent programmer by mistake, who steals our years of work and then sells it to the competitor. That can make us lose our cutting edge. I know this is rare, but such a threat has to be taken under consideration if you're in business. I'll make points of my comments so its easy for everyone to communicate:
Why NDA sucks? Take this scenario, if anyone is capable of suggesting a solution to this scenario I will consider the NDA effective. Ok, here goes: We hire 2 external developers, one of them sells our code as it is to someone else after a year. You are no longer in touch with any of the developers, how are you supposed to find out who ripped you off? NDA does provide a purpose, but you can't rely completely on that. At least we cannot.
I did not meant to offend anyone while I was posting this question, even though unintentionally I did. But again to people answering/commenting like 'I will never ever work with you' or that Men-in-black-gadget thingy: It's not about you, it's a thread about how feasible a given technical solution would be. And if anyone in this community has worked under such an environment.
About 'Trust', of course we won't hire anyone we do not trust. But is that it? Can't someone be deceitful at first? We all trusted a lot of politicians to run our country, did they not fail us ever? So, I'm saying 'trust' is a complete other layer of protection like NDA, and my question was not directed to it. My question is rather directed towards technical measures we can take to avoid such a thing from happening.