Encoding Stream is a simple lib offering Streaming methods of the @std/encoding module.
import { DecodeBase64Stream, EncodeBase64Stream } from '@doctor/encoding-stream'
await (await Deno.open('./deno.json'))
.readable
.pipeThrough(new EncodeBase64Stream())
.pipeThrough(new DecodeBase64Stream())
.pipeTo(Deno.stdout.writable, { preventClose: true })