Gradle - Being told packages do not exist

Hi,

IntelliJ noob here. I've created a project using Kryo and its dependencies as libraries. The project compiles fine in IntelliJ, but if I try to build it into a jar with Gradle in the terminal, it gives me a load of error messages saying that packages don't exist. Interestingly, the only package it complains about is com.esotericsoftware.kryo. I've tried invalidating caches and restarting, but it didn't work.

I'm using the libGDX game development framework if it makes any difference. I'll post a stack trace or whatever you want if you ask. Any insight at all into this problem would be greatly appreciated.