I have a feeling you'll love tau.

I was talking more about physical constants, like magnetism, gravity, planck, etc. But sure, mathematical ones work, too. Probably even worse than physical constants doubling, since the doubling of mathematical ones would imply the corruption of reality itself.

Constants are known at compile time, and therefore are more performant as they don’t need to be reasoned about at runtime.

These days it’s not much of a performance boost but never a bad idea to use constants where appropriate.