@jamie-purchase you need to update dependencies section of build.gradle (add used dependency there). Gradle supports adding dependencies from repositories and also from local files system (if jar-library was built locally and was not published as artifact)

yeah I was looking at http://zweifisch.github.io/kotlin-with-gradle.html and it shows something like

dependencies {
    ...
    compile 'com.github.kevinsawicki:http-request:6.0'
    ...
}

but I can't find an example of the syntax for path/classpath to/for local jar

compile fileTree(dir: ‘imports’, include: ‘*.jar’) where imports is a directory with jar in root project

brilliant thanks

You can do that or you can create a local repository... On the project that is going to be imported, add this to your build.gradle adjusting the path as you prefer:

uploadArchives {
    repositories {
        flatDir dir: "${System.getProperty('user.home')}/.gradle/repos"
    }
}

Now you have that directive, use it to compile and upload your class to the repo. On the other project, add this to the repositories:

repositories {
    flatDir dirs: "${System.getProperty('user.home')}/.gradle/repos/"
    mavenCentral()
    }
}