How to install packages for service in Railway (NixPacks)

NixPacks is like docker file for setup your service.

I have 2 packages need to be installed to able to use a library convert pdf to images: 'graphicsmagick', 'ghostscript'

In Railway, to modify nixpacks, just need to create nixpacks.toml file in the root folder.

Below is a simple nixpacks file just to install above packages into my service:

# https://nixpacks.com/docs/configuration/file

[dependencies]
# List any additional dependencies if needed
nodejs = "18.x"

[phases.setup]
    aptPkgs = ['...', 'graphicsmagick', 'ghostscript']