Java's Maven has been the nicest package management tool I've ever worked with. Apart from the fact that definitions are a bit verbose, it supported everything

Java's Maven has been the nicest package management tool I've ever worked with. Apart from the fact that definitions are a bit verbose, it supported everything I've ever wanted from such a tool: 1. Clear definitions of what is an artifact that it manages, easily described in a versioned file but still separate from your source code 2. Simple support to combine internal and external sources 3. Support for interacting with other package ecosystems (you can easily write a pom.xml for any other kind of package and reference it from your Java projects) 4. Not picky about version number formats 5. Not reliant on other tools to handle any step of package management (except for compilation, of course) 6. Works at the project level and has no problems about different versions being used in different projects on the same machine (with a shared cache for efficiency)