[assbuttbuttass]

I use lowercase for my personal environment variables. It works well since most programs only depend on variables in all caps. Hadn't thought of using MY_

[chrisweekly]

Case-sensitivity reduces portability. "Different strokes", I guess. (literally and figuratively!)

[yencabulator]

https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1...

> Uppercase and lowercase letters shall retain their unique identities and shall not be folded together.

> The name space of environment variable names containing lowercase letters is reserved for applications.