Hi Glavo, My company is currently working on something you can think of as jpackage++. Amongst other tasks it invokes jlink to create a JDK distribution for each targeted operating system. It has JPMS support so I'll post about it on this list when a release is available for public download.
We had the same thoughts as you. JMODs look quite wasteful but as Alan points out, they are the raw inputs to an optimization pipeline. In theory jlink can do anything. Jigsaw is a 'finished' project, so there is unlikely to be any changes to OpenJDK packaging anytime soon. The best way is to lead by example. Unfortunately that would mean creating a new JDK distribution and some bandwidth costs, so you might be better off asking Microsoft, Amazon or some other JDK distribution to try something new here. Although we can ask for OpenJDK to lead by example by making suggestions, realistically the relevant people are engaged on other higher impact projects right now. It's just the way it is. You've suggested several bits of JMOD related low hanging fruit. It's probably best to just write a specification and then implement them! You/I/we could: 1. Take some JDKs and make the JMODs available as separate downloads. Write a simple spec that defines a URL convention, so given a JDK URL the platform specific versions and JMODs can be easily located via string interpolation. Then try and get Amazon/Microsoft/etc to implement the spec. 2. Define a convention so the target platform is incorporated into JMOD file names. Then a single set of JMODs can be used to create linked JVMs for all supported platforms at once. 3. More ambitiously, extend the JMOD format with platform specific directories and write a classloader library that extracts/loads native libraries on the fly. Then the JAR format can be replaced with JMODs, such that a single file represents a truly cross-platform artifact even for cases like JavaFX or java.base, where native libs/different classes are required. For bonus points, fork the clever jimage format to a separate spec so the benefits of jimage's perfect hashing and string dedupe can be obtained from Maven Central downloads, without requiring OpenJDK to commit to the format. None of these projects are difficult. We've considered doing some of them already, but there were always higher priorities. The limits of JMOD are in the end just a disk space/bandwidth waste, so we focus for now on higher impact developer productivity issues.
