uber/jaeger-client-node: backend wont receive data

I'm currently looking into different openTracing Tracer-Implementations. I want to use uber/jaeger-client-node but the backend won't receive my traces.

Here is what I did: I started the all-in-one docker image: docker run -d -p5775:5775/udp -p16686:16686 jaegertracing/all-in-one:latest

Next, i wrote a simple example application: Gist

But when I go to Jaeger UI, nothing is shown about the example service. What did I do wrong?

Thanks

via J. Steger