uutils/coreutils has a `base64` in Rust which just gained better performance due to the base64-simd crate for SIMD: https://github.com/uutils/coreutils/pull/8578

Note that uutils does not work if the file does not fit into memory.

With GNU coreutils:

   $ base64 /dev/zero | head -c 1 | wc -c
   1
With uutils doing the same would exhaust your systems memory until either it freezes or oomd kills the process.

For now. There's no reason this won't/can't be worked on in the future.

Which BusyBox, toybox, and coreutils commands fail with data larger than RAM? Has that been part of the spec yet?

Just realized `LC_COLLATE=C sort` must be specified if you don't want it to ignore leading underscores in sorting due to LC_COLLATE=en_US.utf8 being the default these days.