I can respect that. I never really asked if anyone could make one, just if they had heard of a way to implement composite bows. Though my setting is post apocalyptic, I would scarce say it is modern. Modern guns are not in use, flintlocks (used loosely, commonly switched with wheel locks and other primitive firearms) are the most a character could use. I tried to keep it medieval-esc with some tech implemented every now and then. The idea really came to me when I was having a conversation with some friends, and I made a joke about how I would survive the zombie apocalypse by wearing chainmail and carrying a blunderbuss.
And I don't understand why people refer to it as anachronistic, while Pathfinder is mostly set in medieval times, it is just a system, you build your plot around it any way you want too. Two great examples I have is the pure steam Campaign, and Ponyfinder. Not typical pathfinder settings, but still too the spirit of the game. They use the system to build their own lore and make a story, I love it! And compound bows, I've researched them before posting this on the forums, and I have developed an opinion on them. Much like the gun, they can show up at any point in time someone comes up with the idea, I have seen too many homemade models to say otherwise. The gun can show up any time it wants, all that is required is access to black powder (Which predates the gun by many centuries), and knowledge of metallurgy. The only reason it showed up in Europe when it did is because Europe had spent many years developing intricate church bells, which was beneficial in the construction of the flintlock mechanism. It is safe to assume that if ancient Greece had church, they may have Spartans going into battle with guns thanks to both the technology developed by the bellmaking and trade with Asia. And I did now bump this to make it popular, just wanted to get an idea on how to use compound bows in a campaign when I do. Plus, I do suppose I am somewhat Anachronistic, as I was also thinking on adding zippo style lighters, but I think that could actually be made in medieval times by a tinsmith, just needs someone to think it up.