Earlier today I was discussing the prospect of using Mojang's provided mappings for a spigot derivative with some people. Despite the intent and purpose of these mappings being clearly for modders, such as the servers community, to be able to use their provided obfuscation mappings to make modding easier (see an official statement by Dinnerbone: https://twitter.com/Dinnerbone/status/1293597326561488897), the clear sentiment is that Spigot will not be moving to these mappings and will continue to use md_5's mappings. This is understandable in my opinion and is not what I care about. However, I'd like to address a huge flaw with these mappings that should be changed immediately. There is a glaring flaw with Spigot's obfuscation mappings. Despite Spigot being heralded as a great open-source project, these mappings are under a proprietary license. Why does this matter, you might ask? Simply put, this heavily restricts what derivative projects of Spigot may do, and unfairly so. By these mappings having a proprietary license (as opposed to a MIT license, for example), any derivatives must also be reliant upon the terms and will of Spigot in regards to mappings as all rights are reserved. Here is a likely future scenario which could happen: let's say there is a fork of Spigot (let's call it "Faucet") which wants to expand their project such that plugin developers can write their plugins using Mojang's mappings, with a Mojmap-remapped jar being used at runtime in accordance with Mojang's mappings license. Now, in order to preserve support for Spigot plugins, the maintainers of Faucet may wish to make a mappings file which correctly maps md_5 mappings to Mojang mappings. While this perfectly follows the licensing of the mojang mappings (see the "complete and unmodified" clause), spigot's more restrictive proprietary licensing does not allow for this as the mappings need to be included in this derivative's server distribution for the transformation to function properly. In my opinion (and the opinions of many prominent members of this community), this goes completely against all principles of free and open-source software. My proposed solution to this glaring problem is clear and simple: re-license the Spigot mappings to an open-source license and allow our community to thrive and improve. Almost all other areas of the modding scene are thriving and expanding. Conversely, the servers community and server modding is losing its edge to more innovative projects with clear commitments to open-source like Fabric. Please don't let this happen, @md_5 . We have always been the community to take a lead and help create the most innovative experiences in the game. Let's keep it that way.