ViaVersion — Minecraft plugin

What does ViaVersion do?

ViaVersion provides protocol interoperability: It allows customers of some newer versions of Minecraft to connect to a server with a different version.

Different versions of the same server

ViaVersion adapts the network protocol so that clients of certain new versions of Minecraft can connect to a server using a different version of the protocol. This is convenient when the audience updates the launcher faster than the administration is ready to move the entire project to the new core.

Boundaries of compatibility

A protocol conversion does not mean that all new blocks, mobs, or mechanics will appear on the server. The player can connect with a new version of the client, but the game world is still controlled by the installed server version. The compatibility of specific ranges should be checked against the supported ViaVersion release list, not with a single plugin name.

Update without loss of audience

When a new client is released, some players are updated immediately, and the server remains on the verified version of the kernel. ViaVersion can shorten the period of incompatibility. But once connected, be sure to check inventory, transport, interactions, and game menus: a successful login doesn’t mean every mechanic is completely correct.

Primary source: developer-page.