On Line #15 of the Dockerfile alpine 3.14 is used as the final image, on line #22 of the same Dockerfile postgresql-client is being installed, according to the alpine package search tool this will install version 13x of the package, version 13 of this package (of which includes the tool used to dump the database) would not support the Postgres version 15 or 16 database you are running on Railway. The reason why you end up with an empty backup file is that the backup process does not handle errors correctly (there would be an error about the version mismatch, but that's essentially suppressed) and lets a blank backup file through without erroring out.

To fix the issue of postgresql-client version 13x being installed, simply replace the Dockerfile in your repo with this updated Dockerfile and you should be good to go!

Hi. The new Dockerfile worked perfectly, thank you !!