This is NOT made by me, but is used on servers and DOES work
TrinityCore Haste Patch
With Working Haste Generator
This patch will allow you to set a designated haste cap, that can be used for custom haste servers, using the program given along with it, pretty easy to understand, the patch is outdated and does work on both 4.0 and 3.3.5 Trinitycore.
I will NOT be providing support on making the patch work, you'll either need to do this yourself or manually add it.
Type a mod in the top (aka in mine 0.5) and the number displayed below is the mod you need to add to the script.. in this case a 0.5 modifier would make 6557 the haste cap needed in game to get 0.00 speed for casting ect..
Click Here to download!
Password : a c w e b (no spaces)