WebAssembly and the Future of the JVM Ecosystem
Andrea Peruffo - IBM
WebAssembly is no longer just a browser technology. It is becoming a portable, sandboxed runtime that can be embedded directly inside the JVM. This is already happening.
Projects like QuickJs4J run the QuickJS engine compiled to WebAssembly inside Java applications. QuickJs4J is used inside Microcks, a CNCF project built as a Spring application, proving that this model is already production grade in cloud native environments. SQLite4J executes SQLite compiled to WebAssembly without relying on platform specific JNI binaries.
These examples demonstrate a new execution model for Java: portable native capabilities, strong isolation, and safer extensibility without classloader hacks.
In this session we explore what WebAssembly enables today for Java and Spring developers. We will look at embedding Wasm runtimes in JVM applications, compare this model with JNI and traditional scripting engines, and discuss architectural use cases such as plugin systems, policy engines, and sandboxed extensions inside Spring applications.
WebAssembly is not replacing Java. It is extending it. And it is already reshaping what the JVM can safely execute.