I am planning to work on a project called Infinity which can be found in the InfinityPowered organization. This is supposed to hold a server-like plugin that can be used to make plugins that may want to utilize different worlds for different custom made gamemodes that have their own separate, gamemode specific player data management.
I am also currently contributing to the CommandAPI, a Bukkit/Spigot/Paper/Velocity command framework that uses Brigadier to create better commands.