Trade plugin is a plugin that allows players to trade items with each other. I recorded the whole process of creating it from scratch. The video course is more than 6 hours long and covers everything from start to finish.

Blog post: https://restoremonarchy.com/blog/unt04-trade-plugin-from-scratch
Video course: https://restoremonarchy.com/videos/6650b420-0827-4e8a-921b-3967393561ef