Does anyone has an implementation of the Base64 encoder/decoder for multiplatform?

We have a common encoder in https://gitlab.com/serebit/strife, but it's only about half as fast as Java's built-in encoder.

maybe okio will be a good option soon?

Kinda surprised #ktor doesn't have a builtin base64 encoder tbh

That was a surprise for me too, but it seems there's a feature request in Kotlin but is not a priority, from my perspective, encoding for base 16/64 should be

Okio works in 2.3, yes.