The source code from mineplex 2018 leak with commit history dating back to 2014, it requires a lengthy setup to get functional but is a reasonably easy compile if you know what your doing just have to repatch the spigot

Chiss 2a65086b70 Added Milk the Cow ... Maps now set Min/Max Y		2013-09-12 08:57:51 +10:00
Maps	Bob wants to play!	2013-08-29 15:55:49 +10:00
Plugins	Added Milk the Cow	2013-09-12 08:57:51 +10:00
TestApps/LOCTester	Initial Commit	2013-08-27 08:14:08 -07:00
TexturePack	Initial Commit	2013-08-27 08:14:08 -07:00
Webserver/ServerHandler	Initial Commit	2013-08-27 08:14:08 -07:00
Website	Added DynamicServer for bungee.	2013-09-05 02:11:47 -07:00