java-tutorials/libraries-concurrency/src/main/java/com/baeldung/quasar/App.java

package com.baeldung.quasar;

import co.paralleluniverse.fibers.Fiber;

public class App {
    public static void main(String[] args) {
        new Fiber<Void>(() -> {
            System.out.println("Inside fiber coroutine...");
        }).start();
    }
}