Install mingw. From msys shell run "make -f makefile.win" goto commandline prompt and run the wav_encoder.exe "wav_encoder.exe D:\wav_files" ...

A React Native library for converting WAV audio files to MP3 format using the LAME encoder. This library provides native implementations for both iOS and Android platforms.

I use Exact Audio Copy along with the freeware BladeEnc encoder to make my mp3s straight from CDs. While I don't do the step of going from .wav to .mp3 myself, I'm sure there are plenty of frontends ...