Some restrictions to keep in mind, however, are that this shader doesn't support OptiFine, relies on Iris ... the look of your game with little to no hits to your overall performance.

It is also recommended that you use Iris instead of Optifine ... s hard to beat for almost no performance impact. Named SEUS for short, Sonic Ether’s Unbelievable Shaders improves the realism ...

Mojang is adding vanilla, native shaders to Minecraft with the Vibrant Visuals update. This is the first time non-modded shaders will be a part of Minecraft.