Just looking for some perspective on a little problem (if it even is a problem) I am having. I made a bomb prop for airsoft and paintball games using an Arduino and some other parts. I put the code and parts lists up on my website in case anyone wants to make their own, but I also sell "easy assembly" kits. I have recently learned that someone is using my code and exact parts list to make their own props for commercial resale. They didn't even bother to fix a spelling mistake I made on one of the menus.
Do I have any options here, or am I out of luck, since I made the code freely available? Or am I looking at this wrong, and its not even a problem? My code is not licensed under any open source license, but if anyone asks I tell them the following: No commercial resale, keep my current copyright header, and of course, make any changes they make freely available for others to download.