Will There Be Module Hell?

Project Jigsaw in Java 9 aims to escape JAR hell but falls short on the most critical issue: conflicting versions of third-party libraries. While Jigsaw solves unexpressed/transitive dependencies and shadowing, it explicitly does not support loading multiple versions of the same module in a single configuration. The author argues this omission means version conflicts will persist as 'module hell.' A proposal is made to allow developers and build tools to pass explicit multi-layer configurations at launch time, enabling the JVM to handle version conflicts without requiring changes to the module system itself.