A Java 8+ Jar & Android APK Reverse Engineering Suite (Decompiler, Editor, Debugger & More)

Apache Groovy: A powerful multi-faceted programming language for the JVM platform

Eclipse OpenJ9: A Java Virtual Machine for OpenJDK that's optimized for small footprint, fast start-up, and high throughput. Builds on Eclipse OMR (https://github.com/eclipse/omr) and combines with the Extensions for OpenJDK for OpenJ9 repo.

JPHP - an implementation of PHP on Java VM

A Java to JavaScript transpiler.

Java to Closure JavaScript transpiler

Janino is a super-small, super-fast Java™ compiler.

Java bytecode to WebAssembly compiler

A GeekTime course about constructing a compiler.

Esper Complex Event Processing, Streaming SQL and Event Series Analysis

Framework to interpret and transpile JVM bytecode to JavaScript, OpenCL or WebAssembly.

Bytecode to source converting Java & Kotlin code into JavaScript, C++, D, C#, PHP, AS3, Dart and Haxe and run it everywhere. Also use JVM code in your favourite language as a library.

The implementation of the Rascal meta-programming language (including interpreter, type checker, parser generator, compiler and JVM based run-time system)

Utility class to compile java source code in memory

Library to read, write, analyze, and process java bytecode

The Whiley Compiler (WyC)

A next-gen Ide for JVM development on Android

SquirrelJME is a Java ME 8 Virtual Machine for embedded and Internet of Things devices. It has the ultimate goal of being 99.9% compatible with the Java ME standard.

Cb (C flat) compiler. Cb is simplified C.

100% Java compatibility and Functional Programming.