This is magic-wormhole in a docker container.
Run the container like so:
docker run -it --rm -v /path/to/storage:/tfr mcrmonkey/magicwormhole
docker run -it --rm -v /path/to/storage:/tfr mcrmonkey/magicwormhole send
file.txt
docker run -it --rm -v /path/to/storage:/tfr mcrmonkey/magicwormhole
receive