log everything to stderr

src/lib.rs

@@ -38,7 +38,7 @@ pub async fn serve(port: Option<i32>, tz: Option<String>) -> Result<(), Box<dyn
     loop {
         let (mut sock, addr) = listen.accept().await?;
 
-        println!("{}: connected", addr);
+        eprintln!("{}: connected", addr);
         tokio::spawn(async move {
             if let Err(e) = read_req(&mut sock).await {
                 eprintln!("{}: {}", addr, e);