Panama JAR on Maven Central contains no class files

[WtzLAS]

When I was trying to use panama runtime type to create engine but failed no matter how I set the dependency.

It constantly says:

5/08, 2026 4:33:33 AM ai.tegmentum.wasmtime4j.factory.WasmRuntimeFactory create
INFO: Creating WebAssembly runtime with type: PANAMA
ai.tegmentum.wasmtime4j.exception.WasmException: Requested runtime type PANAMA is not available and no suitable fallback found
        at ai.tegmentum.wasmtime4j.factory.WasmRuntimeFactory.create(WasmRuntimeFactory.java:104)
        at mic.Main$.run$$anonfun$1(Main.scala:36)
        at mic.Main$.run$$anonfun$adapted$1(Main.scala:42)
        at apply @ mic.Main$.run(Main.scala:42)
        at flatMap @ mic.Main$.run(Main.scala:34)
        at main$ @ mic.Main$.main(Main.scala:32)
        at main$ @ mic.Main$.main(Main.scala:32)
        at main$ @ mic.Main$.main(Main.scala:32)

For context I am using this from a currently private Scala 3 project running on macOS Tahoe with Liberca JDK 25.

I tried to make it log FINE messages but failed, so I manually executed Class.forName("ai.tegmentum.wasmtime4j.panama.PanamaWasmRuntime") on the first line of main function, and here is what I got:

java.lang.ClassNotFoundException: ai.tegmentum.wasmtime4j.panama.PanamaWasmRuntime
        at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:580)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:490)
        at java.base/java.lang.Class.forName0(Native Method)
        at java.base/java.lang.Class.forName(Class.java:467)
        at java.base/java.lang.Class.forName(Class.java:458)
        at mic.Main$.run$$anonfun$1(Main.scala:35)
        at mic.Main$.run$$anonfun$adapted$1(Main.scala:42)
        at apply @ mic.Main$.run(Main.scala:42)
        at flatMap @ mic.Main$.run(Main.scala:34)
        at main$ @ mic.Main$.main(Main.scala:32)
        at main$ @ mic.Main$.main(Main.scala:32)
        at main$ @ mic.Main$.main(Main.scala:32)

And I decided to check the JAR file to see if it is corrupted but I redownloaded from the central repo multiple times but only native libraries are found.

I assume this is a packaging issue?

[rapus95]

EDIT: My understanding of the build pipeline might be off:

This location: https://github.com/tegmentum/wasmtime4j/blob/master/.github/workflows/release.yml#L187 explicitly makes publish use java 21 and hence probably never will include panama files.

And there's also https://github.com/tegmentum/wasmtime4j/blob/master/CONTRIBUTING.md which mentions Java 23+ as prerequisite for Panama development. Am I missing something? Panama should be available from 22 onwards, shouldn't it?

Original:
I believe I've found the root cause of the empty Panama JARs. In the wasmtime4j-panama POM, there is a mismatch between the target Java version and the profile activation logic:

• The Properties: Set source/target to 22.
• The Profiles: The panama-unavailable profile triggers on [,23) (anything below 23).

The Problem:
Since the module targets Java 22, if the release build was performed on a JDK 22 environment, the panama-unavailable profile activated. This set the maven-compiler-plugin phase to none, skipping class compilation entirely. However, the maven-dependency-plugin still ran during prepare-package, resulting in a JAR that contains native binaries but no .class files.

The Fix:
The activation cutoffs should be updated to match the targeted Java 22 finalized Panama API:

• panama-available: Change to [22,)
• panama-unavailable: Change to [,22)