Sponge is a Minecraft modding API implemented on top of Forge that can run vanilla clients as well as any mixture of plugins and mods. It combines the strengths of both server and client modding communities, allowing anyone to mod their game. Anyone who is interested can contribute to Sponge, and it is provided under the MIT license.
The following is a list of SDKs from our SDK directory that matched your search term. Though your definition of an SDK may differ, in our world, we define SDKs as platform- specific tools for consuming existing APIs of the sort we list in our API directory. For example, the Ruby SDK for consuming the Twitter Ads API. If you think an SDK, API, or other asset is missing from our directory, be sure to check our guidelines for making contributions to ProgrammableWeb.