(edited) this one also: 
 - https://github.com/monix/monix
 - https://monix.io/api/3.0/monix/eval/Fiber.html => there’s one:

```java
        fiberExecutor = new ThreadPoolExecutor(
                0,
                Integer.MAX_VALUE,
                60,
                TimeUnit.SECONDS,
                new SynchronousQueue<Runnable>(),
                new DaemonThreadFactory("Ruby-" + getRuntimeNumber() + "-Fiber"));

```