GraalVM 25 has just been released, bringing a bunch of improvements to Oracle’s tool for turning Java code into native binaries. Alongside it, Oracle rolled out JDK 25, marking a significant update in the Java ecosystem. These updates aim to make native image generation more precise, faster, and more secure.

Enhanced Native Image Capabilities

One of the biggest upgrades in GraalVM 25 is better points-to analysis in Native Image. This means the tool can now more accurately figure out what parts of the code are needed, helping to shrink the final binary size and boost efficiency. By default, the new version enables Whole-Program Sparse Conditional Constant Propagation (WP-SCCP), which improves static analysis precision. This can lead to smaller binaries and more optimized code.

GraalVM 25 also introduces a static profiler based on XGBoost, a machine learning model. It helps identify which methods are “hot” or “cold,” guiding the compiler to optimize better and reduce unnecessary code. Additionally, an experimental feature called RelativeCodePointers aims to cut down on relocation entries, which can further trim down executable sizes. Security is also a focus, with a new advanced obfuscation feature that re-names symbols in native images to make reverse engineering harder.

Polyglot and WebAssembly Support Gets Better

GraalVM isn’t just for Java anymore. The latest version improves support for other languages and runtimes. For example, GraalJS, the JavaScript engine built on GraalVM, now supports importing WebAssembly modules directly during source code parsing, making it simpler to work with WebAssembly in JavaScript projects. The ECMAScript 2025 standard is enabled by default, keeping GraalVM up to date with modern JavaScript features.

GraalWasm, the WebAssembly runtime, now returns a module object that’s compiled but not yet instantiated. This change makes it easier to manage WebAssembly modules more efficiently. For Python developers, GraalPy now offers a full Python 3.12.8 runtime with a standard REPL, available on Windows. This opens up more possibilities for Python on the JVM, especially for those integrating multiple languages.

Focus Shift and Future Plans

Oracle has announced that GraalVM will move away from Java-specific support. The focus will shift toward non-Java languages like GraalJS and GraalPy. The last GraalVM release supported as part of Oracle Java SE was version 24. Moving forward, customers needing updates for older versions will have to go through Oracle Support.

One big change is the discontinuation of Early Adopter features like Native Image for Java SE users. Instead, Oracle and the broader community are investing in OpenJDK projects like Project Leyden, which aims to improve Java’s startup time, peak performance, and footprint. This shift suggests that the future of GraalVM will be more about supporting multiple languages and improving overall performance rather than tight integration with Java itself.

In summary, GraalVM 25 brings powerful new features for native image optimization, better support for WebAssembly and JavaScript, and a clear direction toward polyglot development. While Java-specific tools are winding down, the broader ecosystem is moving ahead with exciting innovations that could benefit many developers working across different programming languages.

Inspired by

• https://www.infoworld.com/article/4061937/graalvm-25-arrives-backed-by-jdk-25.html

Sources

• gmpg.org
• graalvm.org
• graalvm.org
• github.com
• oracle.com