CssBuilder | Builder pattern for CSS classes | Web Framework library

If you compileInclude external resources (which is possible, but should be your last resort), unfortunately you will need to include all transitive dependencies as well. You're including jayway/jsonpath, and gson is missing. So you'll need to compileInclude gson. And as you say, when you do that, a different library is missing - so you'll need to include it as well.

That's part of the reason why this should be your last resort.

An alternative is: Check if jayway/jsonpath or gson are OSGi bundles themselves - in which case you can just drop them into Liferay's deploy folder and they'll be dynamically resolved. Of course, in this case their transitive dependencies need to be resolvable as well, so you might need to deploy a couple more bundles than just these two. But this way, all modules that use these libraries will share the same bundle.

Either way, you can inspect a bundle's MANIFEST.mf for imports to figure out what they depend on. Note: there are mandatory and optional dependencies in there. You'll need to satisfy the mandatory ones and the optional ones that you're using. If the libraries in question aren't bundles, they're managing their dependencies differently. I'd at least suggest to the project teams to OSGi'ify their packages - but that's a fix for the long run.

There's a chapter on this on Liferay's University's (free, registration required) course OSGi Basics, called "Bringing along your dependencies" (disclaimer: by yours truly), where I still like the animated special effect visualizing the option to compileInclude and what it does to file size)

If I get you right, you can't modify your build.gradle, but you can modify your settings.gradle or you want to add a settings.gradle file to a project that does not have a settings.gradle file right now. In this case, you can simply configure your project(s) using the Gradle instance provided by the Settings object that is used to evaluate the settings.gradle file: