Hi, I've been trying to build a stub for GRASP running in the Android environment. My earlier prototype was written in Java, based on the scripts from a github project called 'buildAPKs', that lets one build Android projects on Android (using the Termux app). Also, I found a github project that showd how to build apps written in Kawa for Android, and even managed to build and run an example application: https://github.com/abarbu/android-kawa However, the caveat is that it comes with a kawa.jar file with version 1.13, which is quite old (and there are many features from the more recent Kawa releases that GRASP relies on). But when I try to build the KawaHello example using a kawa.jar built from the most recent version, I get an error from the Android's ''dexer" tool (which translates JVM bytecode to Dalvik/ART): PARSE ERROR: unsupported class file version 61.0 ...while parsing gnu/bytecode/Access.class So, what I suppose happens, is that the javac which builds Kawa emits byte code that is unsupported by dx. I tried building Kawa having passed --with-java-source=7 to the 'configure' script, but that didn't help. I also tried cosplaying javac by ecj (which is the compiler that the buildAPKs uses), but this results with a bunch of warnings and some errors: 180. WARNING in /data/data/com.termux/files/home/Kawa2/gnu/kawa/util/AbstractHashTable.java (at line 243) static class AbstractEntrySet, K, V> extends AbstractSet ^^^^^ The type parameter Entry is hiding the type Map.Entry ---------- 181. ERROR in /data/data/com.termux/files/home/Kawa2/gnu/kawa/util/AbstractHashTable.java (at line 287) nextEntry = htable.table[nextIndex]; ^^^^^^^^^^^^^^^^^^^^^^^ Type mismatch: cannot convert from Map.Entry to Entry ---------- 182. ERROR in /data/data/com.termux/files/home/Kawa2/gnu/kawa/util/AbstractHashTable.java (at line 298) nextEntry = htable.getEntryNext(currentEntry); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Type mismatch: cannot convert from Map.Entry to Entry ---------- I'm not really sure where these errors stem from - I suppose ecj supports a different subset of Java than the one that was used to write Kawa (I was forcing source and tarfet I also tried aliasing javac as javac -release 7, but it still seens to produce the class file version 61.0. Does anyone know how to produce a kawa.jar that would satisfy the dexer? (The dexer version from the termux repo is 1.16)