README should describe differences between this project and std.experimental.allocator

[pbackus]

Currently, the only way to discover what changes have been made to stdx-allocator relative to std.experimental.allocator is to either read the code, or dig through old issue and PR discussions. The project's README should give a brief but complete description of the ways in which the two packages have diverged, with special attention given to breaking changes.

[aminya]

I agree. I find this confusing too

[denizzzka]

Maybe it is time to deprecate this package?

Nothing has changed in both of them for a long time

dlang-community/discussions#27