GraalVM is a high-performance JDK distribution that compiles your Java applications ahead of time into standalone binaries. These binaries start instantly, provide peak performance with no warmup, and use fewer resources. You can use GraalVM just like any other Java Development Kit in your IDE.

The project website at https://www.graalvm.org/ describes how to get started, how to stay connected, and how to contribute.

Documentation

Please refer to the GraalVM website for documentation. You can find most of the documentation sources in the docs/ directory in the same hierarchy as displayed on the website. Additional documentation including developer instructions for individual components can be found in corresponding docs/ sub-directories. The documentation for the Truffle framework, for example, is in truffle/docs/. This also applies to languages, tools, and other components maintained in related repositories.

Get Support

• Open a GitHub issue for bug reports, questions, or requests for enhancements.
• Join the GraalVM Slack to connect with the community and the GraalVM team.
• Report a security vulnerability according to the Reporting Vulnerabilities guide.

Repository Structure

This source repository is the main repository for GraalVM and includes the following components:

Directory	Description
.devcontainer/	Configuration files for GitHub dev containers.
.github/	Configuration files for GitHub issues, workflows, ….
compiler/	Graal compiler, a modern, versatile compiler written in Java.
espresso/	Espresso, a meta-circular Java bytecode interpreter for the GraalVM.
regex/	TRegex, a regular expression engine for other GraalVM languages.
sdk/	GraalVM SDK, long-term supported APIs of GraalVM.
substratevm/	Framework for ahead-of-time (AOT) compilation with Native Image.
sulong/	Sulong, an engine for running LLVM bitcode on GraalVM.
tools/	Tools for GraalVM languages implemented with the instrumentation framework.
truffle/	GraalVM’s language implementation framework for creating languages and tools.
visualizer/	Ideal Graph Visualizer (IGV), a tool for analyzing Graal compiler graphs.
vm/	Components for building GraalVM distributions.
wasm/	GraalWasm, an engine for running WebAssembly programs on GraalVM.

Related Repositories

GraalVM provides additional languages, tools, and other components developed in related repositories. These are:

Name	Description
FastR	Implementation of the R language.
GraalJS	Implementation of JavaScript and Node.js.
GraalPy	Implementation of the Python language.
GraalVM Demos	Several example applications illustrating GraalVM capabilities.
Native Build Tools	Build tool plugins for GraalVM Native Image.
SimpleLanguage	A simple example language built with the Truffle framework.
SimpleTool	A simple example tool built with the Truffle framework.
TruffleRuby	Implementation of the Ruby language.

License

GraalVM Community Edition is open source and distributed under version 2 of the GNU General Public License with the “Classpath” Exception, which are the same terms as for Java. The licenses of the individual GraalVM components are generally derivative of the license of a particular language (see the table below).

Component(s)	License
Espresso, Ideal Graph Visualizer	GPL 2
GraalVM Compiler, SubstrateVM, Tools, VM	GPL 2 with Classpath Exception
GraalVM SDK, GraalWasm, Truffle Framework, TRegex	Universal Permissive License
Sulong	3-clause BSD