Why not use a rust library for v4.local (or StableLib XChacha20 library)?

[Extarys]

Out of curiosity, mostly, but also because symmetric encryption tend to be faster/more efficient. This could be a simple command to compile the library on the user's machine, if the user wish to use vX.local that isn't currently supported by only using JS.

EDIT I also found a pure TS implementation of XChacha20here https://github.com/StableLib/stablelib/tree/master/packages/xchacha20