Apply gradle custom jar plugin

The chapter 58 of the user guide has all the information you need. In summary:

• Put your myPlugin.properties inside your project structure, in src/main/resources/META-INF /gradle-plugins/
• Build your jar like you usually do

• In the script you wish to use this plugin, add a buildscript closure to something like:

  buildscript {
      repositories {
          flatDir dirs: "build/libs"
      }
      dependencies {
          classpath "your.group:your-plugin:1.0.0"
      }
  }
  

Or whatever settings for repositories and dependencies you wish, but you need to use the classpath configuration as I've done here. I don't think you can (or should!) add the jar to the plugin dir of Gradle like you did.

Note: the flatDir does not resolve transitive dependencies. The same rule for dependency management applies to the buildscript, so you can use a regular maven or ivy repository to deploy your plugin.