I'm trying to setup a custom buildpack that can provide libzmq if necessary. The issue I ran into is that libzmq requires uuid-dev, which is in utils-linux. I can use vulcan to build utils-linux, but then was faced with the question: how do I get that version of utils-linux onto the machine that is building libzmq.
Rather than setup a custom buildpack for vulcan that included utils-linux, I added an option to vulcan build that lets me include any number of vulcan built dependencies. These dependencies get pulled down via http and expanded into a deps folder, which is then added to the LDFLAGS/CFLAGS/etc environment variables.
Fixing cradle api
Fixing dependency versions
adding support for vulcan build -d <dep1>,...,<depN>
dependencies are other vulcan built libraries which are required for the current build