FS2 CSV->TXT parser

import java.nio.file.{Paths, StandardOpenOption}
import fs2._
import cats.effect.{Blocker, ExitCode, IO, IOApp}
import cats.implicits.toFunctorOps

object Hello extends IOApp {
  override def run(args: List[String]): IO[ExitCode] = {
    def program: Stream[IO, Unit] = {
      Stream.resource(Blocker[IO]) flatMap { blocker =>
        val stream = io.file.readAll[IO](Paths.get("/Users/macbook1/a.csv"), blocker, 4096)
        stream
          .through(text.utf8Decode)          // decode bytes as UTF-8
          .through(text.lines)               // get lines removing CR/LF separators
          .drop(1)                           // drop CSV header
          .filter(_.nonEmpty)                // remove empty lines
          .map(_.replaceAll("""['"]""", "")) // remove all ' and "
          .intersperse(",")                  // add commas
          .through(text.utf8Encode)          // encode back to bytes
          .through(io.file.writeAll(Paths.get("/Users/macbook1/b.txt"), blocker, Seq(StandardOpenOption.TRUNCATE_EXISTING)))
      }
    }

    program.compile.drain.as(ExitCode.Success)
  }
}