This was a fantastic, thorough, unbiased explanation. I am going to sully it by weighing in with my opinion: > Java packages are a fine "module" system if you

This was a fantastic, thorough, unbiased explanation. I am going to sully it by weighing in with my opinion: > Java packages are a fine "module" system if you're designing a single large cohesive application that has no dependencies or trust boundaries. I've always thought that Java packages are a fine module system period. They require library authors to be prescient enough to never make backward-incompatible API changes (it's easy, just make a new package any time you want to change your API in an incompatible way). Obviously, the open-source community has fallen down on the job in this respect, and I'm sure there is a widespread opinion that the burden of managing API changes in this way will never be met and so something like Jigsaw is necessary. But I think the required culture change among library authors would be much preferable to adding the complexity of another module system on top of packages. And it's such an easy change for library authors to make to their behavior that there must be at least some hope of being able to reach a consensus around it.