Ever since I started working with Minecraft Servers a few years ago, both for my own and for clients, I have been creating a series of plugins to help extend the functionality and gameplay of Minecraft. Some of which I have released publicly on a platform called SpigotMC.
Some of the plugins that I have created help to extend the basic functionality of the game, such as SCore and RPChat, and others help to add in entire new aspects of gameplay, such as ChestLock and SToken.
All of the work that I have created and released publicly has been designed and developed in a way that I believe can benefit the wider Minecraft community. Whether that be through giving server owners access to basic server functionality or more advanced, game-altering features.
You can check out the full list of plugins that I have developed and released for use by the wider Minecraft community on my SpigotMC profile.