You can always reveal the source code, without giving it an open source license. Of course, this will mean some people might not contribute, but you take what y

You can always reveal the source code, without giving it an open source license. Of course, this will mean some people might not contribute, but you take what you get. Another way is giving it a 'non-commercial use only' stipulation, which might not be lawyer proof. Any of this won't prevent people from trying to profit off of it though. PS: Remember to have an CLA so you won't have any problems with selling it.