docker image, ports and remote connections

soooo, very quickly i stumbled on a problem with my app i was deploying with docker.
the app opens a port and docker allows to redirect ports on the image to different ports on the host, so i was running

docker run -t -i -p 8090:8080 deligo

but i couldn't connect to 8090.
or rather netcat/nc was showing it as busy, but it wouldn't open in a browser.
so what was happening?

luckily the very first search result on duckduckgo provided the insight (stackoverflow.com):

Docker container published ports not accessible

i quickly checked and indeed in my go app i had started my http listener for 127.0.0.1 which as it turns out does not allow remote connections!
quickly changed to 0.0.0.0 and the whole chain works fine now, yeey!