Cacaovm - Just-In-Time (JIT) Compiler

•    Java

cacaovm is a Java Virtual Machine (JVM) which uses Just-In-Time (JIT) compilation to execute Java methods natively. cacaovm uses GNU Classpath or OpenJDK or phoneME as Java runtime library. The cacaovm project started as a research JVM to explore new implementation techniques. The first version for the Alpha was released in February 1997 as a binary.

Eclipse OpenJ9 - A Java Virtual Machine for OpenJDK that's optimized for small footprint, fast start-up, and high throughput

•    Java

Eclipse OpenJ9 is an independent implementation of a Java Virtual Machine. "Independent implementation" means it was built using the Java Virtual Machine specification without using any code from any other Java Virtual Machine. The OpenJ9 JVM combines with the Java Class libraries from OpenJDK to create a complete JDK tuned for footprint, performance, and reliability that is well suited for cloud deployments.

Kaffe - Not Java

•    Java

Kaffe is a clean room implementation of the Java virtual machine, plus the associated class libraries needed to provide a Java runtime environment.

GNU Classpath - Mother of most of the VM

•    C

GNU Classpath provides core class libraries for use with virtual machines and compilers for the java programming language. GNU Classpath 1.0 will be fully compatible with the 1.1 and 1.2 API specifications, in addition to having significant compatibility with the 1.3, 1.4, 1.5 and 1.6 APIs.

JC Virtual Machine - Converts Java to C

•    Java

JC Virtual machine converts Java class files to C source code. It could also compiles with GCC and loads them with built-in ELF loader. Additional to that, JC provides a complete Java runtime with optimization to increase performance.

Graal - High-Performance Polyglot VM

•    Java

GraalVM is a universal virtual machine for running applications written in JavaScript, Python 3, Ruby, R, JVM-based languages like Java, Scala, Kotlin, and LLVM-based languages such as C and C++. GraalVM removes the isolation between programming languages and enables interoperability in a shared runtime. It can run either standalone or in the context of OpenJDK, Node.js, Oracle Database, or MySQL.

Harmony - Open Source Java SE

•    Java

Apache Harmony is a modular Java runtime with class libraries and associated tools. One of the goals of the Harmony project is to create a design modular enough so that parts of the VM can be implemented in different languages. This project started in 2005 and it is under active development.

Java SE - Creator of Java

•    Java

Java Standard Edition provides Java development kit and Runtime to develop and deploy Java programs. Developed by Sun and take over by Oracle. It has support for different environments like Desktop, Embedded, Web, Realtime etc.

IKVM.NET - Java for Mono and .NET Framework

•    Java

IKVM.NET is an implementation of Java for Mono and the Microsoft .NET Framework. It has JVM implemented in .NET. A .NET implementation of Java class libraries. It is interoperable between Java and .NET.

Kaffe

•    C

Kaffe is a clean room implementation of the Java virtual machine, plus the associated class libraries needed to provide a Java runtime environment.

SapMachine - An OpenJDK release maintained and supported by SAP

•    Java

This project contains a downstream version of the OpenJDK project. It is used to build and maintain a SAP supported version of OpenJDK for SAP customers and partners who wish to use OpenJDK to run their applications.

mac - virtual machine in c

•    C

mac is a simple virtual machine created for educational purposes. Here is the accompanied blog post. There is a slightly more extended example in the mac-improved folder.

avian - Avian is a lightweight virtual machine and class library designed to provide a useful subset of Java's features, suitable for building self-contained applications

•    C++

These are examples of building Avian on various operating systems for the x86_64 architecture. You may need to modify JAVA_HOME according to where the JDK is installed on your system. In all cases, be sure to use forward slashes in the path.Avian is a lightweight virtual machine and class library designed to provide a useful subset of Java's features, suitable for building self-contained applications. More information is available at the project web site.

java-virtual-machine-specification - Chinese translation of The Java® Virtual Machine Specification

Chinese translation of The Java® Virtual Machine Specification.《Java 虚拟机规范（第11版）》中文翻译及示例，Java SE 11 版

Small Deterministic D Embedded Assembler Register Machine

SIDEARM is a minimal, virtual register machine that acts as an interpreter/shell for valid AVR assembly language execution in real-time by the virtual machine.

kernel virtual machine

•    C

KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko. Using KVM, one can run multiple virtual machines running unmodified Linux or Windows images. Each virtual machine has private virtualized hardware: a network card, disk, graphics adapter, etc.

erjang - A JVM-based Erlang VM

•    Java

Erjang is a virtual machine for Erlang, which runs on Java 7.It loads Erlang's binary .beam file format, compiles it into Java's .class file format, and loads it into the JVM. It will eventually have it's own implementation of all Erlang's BIFs (built-in-functions) written in Java.

Packer - Build Automated Machine Images

•    Go

Packer is a tool for building identical machine images for multiple platforms from a single source configuration. It is lightweight, runs on every major operating system, and is highly performant, creating machine images for multiple platforms in parallel.

gasm - An Experimental Wasm Virtual Machine for Gophers

•    Go

A minimal implementation of v1 WASM spec compatible virtual machine purely written in go. The vm can be embedded in your go program without any dependency like cgo, and enables Gophers to write wasm host environments easily. The vm should be used only for providing sandbox environments embedded in your Go program since we have not implemented validation of wasm binary.

HHVM - HipHop Virtual Machine for PHP

•    PHP

HHVM (aka the HipHop Virtual Machine) is a new open-source virtual machine designed for executing programs written in PHP. HHVM uses a just-in-time compilation approach to achieve superior performance while maintaining the flexibility that PHP developers are accustomed to.