JVM

Awesome JVM Awesome

A curated list of awesome JVM low level, performance and non-framework related stuff.

- [Communities](#communities)

Bytecode

Tools for bytecode manipulation and analysis.

  • asmtools - Used to develop tools for the production of Java .class files.
  • Byte Buddy - Code generation library creating Java classes at runtime without the help of a compiler.
  • Jitescript - Bytecode generation library similar to BiteScript.

Garbage collectors

Garbage collectors for the JVM.

  • Azul Pauseless Garbage Collection - Providing continuous, pauseless operation for Java applications.
  • Balanced GC - GC policy available in the Java Virtual Machine for IBM WebSphere Application Server V8.
  • Epsilon GC - Completely passive GC implementation with bounded allocation limit, and lowest runtime performance overhead possible.
  • G1 - The Garbage-First Garbage Collector.
  • Shenandoah - Ultra-Low-Pause-Time Garbage Collector.
  • The Garbage Collection Handbook - Book that addresses new challenges to garbage collection made by recent advances in hardware and software.
  • ZGC - Garbage collector optimized for low latency and very large heaps.

Load tools

Tools that generate load and measure the system accurately without coordinated omission

  • Gatling - Asynchronous non-blocking scenario driven load testing tool for testing HTTP servers.
  • wrk2 - A constant throughput, correct latency recording variant of wrk.

Languages

Languages running on the JVM. * Ceylon - Object-oriented, strong and static programming language with an emphasis on immutability, created by Red Hat. * Clojure - Dialect of Lisp created by Rich Hickey. Dynamically typed with emphasis on functional programming. * Erjang - A JVM-based Erlang VM. * Eta - Pure, lazy, strongly typed functional programming language on the JVM. * Frege - Pure functional programming language in the spirit of Haskell. * gojava - Java bindings for Go packages. * Golo - A simple dynamic language that makes extensive usage of invokedynamic. * Groovy - Optionally typed and dynamic language, with static-typing and static compilation capabilities. * Java - General-purpose, concurrent, strongly typed, class-based object-oriented language. * JRuby - Implementation of the Ruby language on the JVM. * JPHP - PHP on the Java VM. * Jython - Python for the Java Platform. * Kawa - Extension of the Scheme language, which is in the Lisp family of programming languages. * Kotlin - Statically typed programming language for the JVM, Android and the browser. * LuaJ - Java-centric implementation of lua vm built to leverage standard Java features. * Nashorn - Lightweight high-performance JavaScript runtime in Java with a native JVM. * OCaml-Java - Supports OCaml language v4. Generates plain Java bytecode and have seamless integration with Java. * Rembulan - Rembulan is an implementation of Lua 5.3 for the JVM, written in pure Java with minimal dependencies. * Renjin - JVM-based interpreter for the R language for the statistical analysis * Scala - Strong and static programming language that combine object-oriented and functional programming ideas. * Xtend - Flexible and expressive dialect of Java, which compiles into Java 5 source code.

Machine Learning

  • Deeplearning4j - Open-Source, Distributed, Deep Learning Library for the JVM.
  • H2O - Fast statistical, machine learning & math runtime.
  • Smile - Statistical Machine Intelligence & Learning Engine.

Memory and concurrency

Tools and data structures for efficient memory layout and concurrent access.

  • Agera - Reactive Programming for Android by Google.
  • Agrona - Library of data structures and utility methods that are a common need when building high-performance applications.
  • Apache Arrow - A high-performance cross-system data layer for columnar in-memory analytics.
  • bloofi - Java implementation of multidimensional Bloom filters
  • Cap’n Proto - Insanely fast data interchange format and capability-based RPC system.
  • caffeine - A high performance caching library for Java 8.
  • Chronicle-Bytes - Low level memory access wrappers.
  • Chronicle-Queue - Micro second messaging that stores everything to disk.
  • Chronicle-Map - In-memory key-value store designed for low-latency and/or multi-process applications.
  • clj-ds - Clojure's data structures modified for use outside of Clojure.
  • colfer - Binary serialization format and class generator.
  • commons-math - Library of lightweight, self-contained mathematics and statistics components.
  • CuckooFilter4J - Bloom filter replacement for approximated set-membership queries.
  • cyclops - Integration modules for RxJava, Reactor, FunctionalJava, Guava & Javaslang.
  • Eclipse Collections - Collections framework for Java.
  • externalsortinginjava - Sort very large files using multiple cores and an external-memory algorithm.
  • failsafe - A lightweight, zero-dependency library for handling failures.
  • fasttuple - Collections that are laid out adjacently in both on- and off-heap memory.
  • fast-uuid - Java library for quickly and efficiently parsing and writing UUIDs.
  • FlatBuffers - Efficient cross platform serialization library for C++, C#, Go, Java, JavaScript, PHP, and Python.
  • geohash - Java utility methods for geohashing.
  • gs-collections - Goldman Sachs collections framework.
  • hollow - Java library and comprehensive toolset for harnessing small to moderately sized in-memory datasets.
  • high-scale-lib - Cliff Click's High Scale Library.
  • hppc - High Performance Primitive Collections.
  • injector - A new Executor for Java.
  • java-concurrent-hash-trie-map - Java port of a concurrent trie hash map implementation from Scala collections.
  • java-hll - Java library for the HyperLogLog algorithm.
  • JavaFastPFOR - Library to compress and uncompress arrays of integers very fast.
  • java-string-similarity - String similarity and distance measures, including Levenshtein edit distance and sibblings, Jaro-Winkler, Longest Common Subsequence, cosine similarity etc.
  • JCTools - Concurrent data structures currently missing from the JDK.
  • DSL-JSON - High performance JSON library with advanced compile-time databinding.
  • jsoniter - Claims to be the fastest JSON parser ever (copy of DSL-JSON).
  • jOOL - Useful extensions to Java 8 lambdas.
  • Koloboke - Java Collections til the last breadcrumb of memory and performance.
  • LevelDB - Rewrite (port) of LevelDB in Java.
  • lightweight_trie - A very memory-efficient trie (radix tree) implementation.
  • lmdbjni - Java API to LMDB (HawtJNI) which is an ultra-fast, ultra-compact key-value embedded data store written in C.
  • lmdbjava - Java API to LMDB (JNR) which is an ultra-fast, ultra-compact key-value embedded data store written in C.
  • low-gc-membuffers - In-memory circular buffers that use direct ByteBuffers to minimize GC overhead.
  • lwjgl3 - Java library that enables cross-platform access to popular native APIs useful in the development of graphics (OpenGL), audio (OpenAL) and parallel computing (OpenCL) applications.
  • MapDB - Collections backed by off-heap or on-disk storage.
  • mph-table - Minimal Perfect Hash Tables are an immutable key/value store with efficient space utilization and fast reads.
  • mug - A small, zero-dep functional util library originating from Google.
  • netty-buffers - Memory buffer pool implementation similar to jemalloc.
  • ObjectLayout - A layout-optimized Java data structure package.
  • ohc - Java large off heap cache developed for Apache Cassandra 3.0.
  • okio - Modern Java IO library that do clever things to save CPU and memory.
  • onyx-java - Mirrors the Onyx Platform core API by providing a Java equivalent for each component of an Onyx workflow.
  • parquet - Columnar storage format that uses the record shredding and assembly algorithm described in the Dremel paper.
  • PauselessHashMap - A java.util.HashMap compatible map that won't stall puts or gets when resizing.
  • pcollections - A Persistent Java Collections Library.
  • protobuf - Google's data interchange format.
  • Quasar - Lightweight threads and actors for the JVM.
  • rtree - Immutable in-memory R-tree and R*-tree implementations in Java with reactive api.
  • RTree2D - RTree2D is a 2D immutable R-tree with STR (Sort-Tile-Recursive) packing for ultra-fast nearest and intersection queries on plane and spherical surfaces.
  • Reactive Streams - Standard for asynchronous stream processing with non-blocking back pressure.
  • Reactive Streams Utilities - Future standard utilities library for Reactive Streams.
  • RoaringBitmap - A better compressed bitset in Java.
  • rollinghashjava - Rolling hash functions in Java.
  • Reactor - Reactive data applications on the JVM for Java, Groovy, Clojure and other.
  • RxJava - Library for composing asynchronous and event-based programs using observable sequences.
  • SmoothieMap - java.util.Map impl with worst put latencies more than 100 times smaller than java.util.HashMap.
  • Simple Binary Encoding - High Performance Message Codec.
  • splitmap - A parallel bitmap implementation.
  • DataSketches - A Java software library of stochastic streaming algorithms.
  • stormpot - A fast object pool for the JVM.
  • stream-lib - A Java library for summarizing data in streams for which it is infeasible to store all events.
  • streamvbyte - Fast integer compression in C using the StreamVByte codec.
  • TraneIO - High-performance implementation of the Future abstraction.
  • transducers-java - Composable algorithmic transformations independent from the context of their input and output sources.
  • VarInt - No-deps variable int implementation without deps (by Bazel).
  • vavr - Functional Library for Java 8+.
  • wire - Clean, lightweight protocol buffers for Android and Java.
  • Zero-Allocation-Hashing - Hashing any sequences of bytes in Java, including all kinds of primitive arrays, buffers, CharSequences and more.

Metaprogramming

Parsers, interpreters, compilers and source generation targeted for the JVM.

  • Antlr - Parser generator for reading, processing, executing, or translating structured text or binary files.
  • auto - A collection of source code generators for Java.
  • Apache Calcite - Dynamic data management framework and SQL parser plugin.
  • Checker Framework - Compiler plug-ins that find bugs or verify their absence.
  • compile-testing - Testing tools for javac and annotation processors.
  • derive4j - Algebraic data types constructors, pattern-matching, morphisms, optics and typeclasses.
  • error-prone - Catch common Java mistakes as compile-time errors.
  • GHCVM - A Haskell to JVM compiler that supports GHC Haskell.
  • Graal - New experimental just-in-time compiler for Java that is integrated with the HotSpot virtual machine.
  • grappa - Java fork of Parboiled. Write grammars with no preprocessing phase.
  • immutables - Generate simple, safe and consistent value objects.
  • javacc - Parser generator for use with Java.
  • javaparser - Java 1.8 Parser and Abstract Syntax Tree for Java.
  • JavaPoet - A Java API for generating .java source files.
  • jparsec - Builds mini parsers in pure Java a la Haskell Parsec.
  • JSweet - A transpiler from Java to TypeScript/JavaScript.
  • MPS - Design and build extensible DSLs and editors.
  • lombok - Reduce the amount of boilerplate code that is commonly written for Java classes.
  • parboiled - Parsing of arbitrary input text based on parsing expression grammars.
  • Sulong - LLVM IR interpreter written in Java using Truffle and Graal.
  • TeaVM - Ahead-of-time translating compiler (transpiler) from Java bytecode to JavaScript.
  • Truffle - Framework for implementing languages as simple interpreters.
  • Xtext - Framework for development of programming languages and DSLs.

Native

Interconnecting JVM and native code

  • hawtjni - A JNI code generator based on the JNI generator used in Eclipse SWT.
  • Java Grinder - Compile Java bytecode to microcontroller assembly.
  • j2v8 - Java API for Google's V8 JavaScript engine.
  • JavaCPP - JavaCPP provides efficient access to native C++ inside Java.
  • jnr-ffi - Load native libraries without writing JNI code by hand.
  • jssembly - Execution of native assembly from Java.
  • NuProcess - A low-overhead, non-blocking I/O, external Process execution implementation for Java.
  • Project Panama - Enriching the connections between the JVM and APIs used by C programmers.

Network

Tools for network programming, packet capture, monitoring, testing and resiliency.

  • Aeron - Efficient reliable UDP unicast, UDP multicast, and IPC message transport.
  • armeria - Asynchronous RPC/API client/server library built on top of Java 8, Netty 4.1, HTTP/2, and Thrift.
  • Chronicle-Network - A High Performance Network library.
  • comcast - Simulating shitty network connections.
  • gor - HTTP traffic replay in real-time.
  • gRPC - A high performance, open source, general RPC framework that puts mobile and HTTP/2 first.
  • jRT - Measures response time of a java application to socket-based requests.
  • JXIO - Java API over AccelIO (C library), a high-performance asynchronous reliable messaging and RPC library optimized for hardware acceleration.
  • K3PO - Create arbitrary network traffic and behavior to certify whether a network endpoint behaves correctly.
  • muxy - Simulating real-world distributed system failures.
  • Netty - Async event-driven network library for high performance protocol servers & clients.
  • okhttp - An HTTP+HTTP/2 client for Android and Java applications.
  • one-nio - library for building high performance Java servers.
  • proteus-java - Proteus Java Client based on RSocket.
  • reactive-grpc - Reactive gRPC is a suite of libraries for using gRPC with Reactive Streams programming libraries.
  • RSocket - RSocket is a binary protocol for use on byte stream transports such as TCP, WebSockets, and Aeron.
  • SimianArmy - Resiliency tool that helps ensure that your applications can tolerate random instance failures.
  • pcap4j - Java library for capturing, crafting, and sending packets using libpcap.
  • pig - A Linux packet crafting tool.
  • tcpdump - Packet analyzer for network traffic capture.
  • tcpflow - Captures TCP connections flows in a way that is convenient for protocol analysis and debugging.
  • tcpreplay - Pcap editing and replay tools.

Nix tools

Useful nix tools when profiling the JVM and interaction with the host environment* * atoptool - Logging of system and process activity for long-term analysis, highlighting overloaded system. * bcc - Tools for BPF-based Linux IO analysis, networking, monitoring, and more. * Flame Graphs - Visualization of profiled software, allowing the most frequent code-paths to be identified quickly and accurately. * ioping - Simple disk I/0 latency measuring tool. * javap - Disassembles class files into code that reflects the java bytecode. * jhat - Java Heap Analysis Tool * jinfo - Prints configuration information for a given process. * jstack - Prints stack traces of threads for a given Java process. * jstat - Monitors GC and compiler statistics in the JVM. * hwloc - Reports the structure of the processor, number of cores, hyperthreads and cache size. * likwid - Read hardware performance counters on Intel and AMD processors. * numactl - Control NUMA policy for processes or shared memory. * oprofile - System-wide hardware performance monitoring with easy-to-use interface at low overhead. * perf - Linux profiling with performance counters. * perf-tools - Performance analysis tools based on Linux perf_events (aka perf) and ftrace. * sysdig - Capture system state and activity from a running Linux instance, then save, filter and analyze. * sysstat - Performance monitoring tools for Linux. * taskset/process-affinity - Retrieve or set a processes’s CPU affinity. * tiptop - Like top but also shows instructions per cycle (IPC).

Profilers

Tools that provide profiling and tracing information to aid program optimization

  • allocation-instrumenter - Java agent that rewrites bytecode to instrument allocation sites.
  • aprof - Java memory allocation profiler.
  • async-profiler - Sampling CPU profiler for Java featuring AsyncGetCallTrace + perf_events.
  • BTrace - a safe, dynamic tracing tool for the Java platform.
  • Byteman - tracing, monitoring and testing tool for Java
  • bytestacks - Turn JVM bytecode execution into flame graphs.
  • Chronon - Record your entire java program. Replay on any machine.
  • GCeasy - Machine learning guided Garbage collection log analysis tool. Auto-detect problems in the JVM GC logs and recommend solutions to it.
  • GCViewer - GCViewer is a tool that visualizes verbose GC output.
  • grav - A collection of tools to help visualise process execution.
  • hawkshaw - Tools for tracking down memory / JVM problems & generating predictable-as-possible VM behaviour.
  • HdrHistogram - A Histogram that supports recording and analyzing sampled data value counts.
  • hdrhistogram-metrics-reservoir - A Metrics Reservoir implementation backed by HdrHistogram.
  • HdrLogProcessing - Utilities for HDR Histogram logs manipulation.
  • heapster - Production heap profiling for the JVM.
  • honest-profiler - Sampling JVM profiler without the safepoint sample bias.
  • jamm - Measure actual object memory use including JVM overhead.
  • Java Flight Recorder (JFR) - Tool for collecting diagnostic and profiling data about a running Java application with almost no performance overhead.
  • java-sizeof - Memory consumption estimator for Java.
  • jcstress - Experimental harness and tests to aid the research in the correctness of concurrency support in the JVM, class libraries, and hardware.
  • jfr-flame-graph - Converting JFR Method Profiling Samples to FlameGraph compatible format.
  • jfr-report-tool - Tool for creating reports from Java Flight Recorder dumps.
  • jitwatch - Log analyser / visualiser for Java HotSpot JIT compiler.
  • jitwatch-intellij - JITWatch plugin for IntelliJ IDEA.
  • jHiccup - jHiccup is an open source tool designed to measure the pauses and stalls associated with an application’s underlying Java runtime platform.
  • jmh - Micro benchmarks written in Java and other languages targetting the JVM.
  • jmh-compare-gui - GUI for comparing JMH results.
  • JOL - Analyze actual object layout schemes, footprint, and references in JVMs.
  • JProfiler - Helps resolve performance bottlenecks, pin down memory leaks and understand threading issues.
  • JVMTI - Provide a native API to inspect the state and to control the execution of applications running in the JVM.
  • jvmtop - Lightweight console application to monitor running jvms on a machine in top-like manner.
  • jvm-profiler - Java Agent to collect various metrics and stacktraces for Hadoop/Spark JVM processes in a distributed way.
  • MAT - Java heap analyzer that help find memory leaks and reduce memory consumption.
  • leakcanary - A memory leak detection library for Android and Java.
  • metrics - Measure the behavior of critical components in production environment.
  • micrometer - An application metrics facade for the most popular monitoring tools.
  • osquery - osquery is an instrumentation framework that expose the operating system as a high-performance relational database.
  • Overseer - Low-Level Hardware Monitoring and Management for Java.
  • OpenTracing - A vendor-neutral open standard for distributed tracing.
  • perf-map-agent - Generate method mappings to use with the linux perf tool.
  • perfj - Linux perf for java programs.
  • polarbear - A tool to help diagnose OutOfMemoryError conditions.
  • Riemann JVM Profiler - JVM agent which sends function-level profiler telemetry to a Riemann server for analysis, visualization, and storage.
  • statsd-jvm-profiler - JVM agent profiler that sends profiling data to StatsD.
  • Swiss Java Knife - Small set of tools for JVM troublshooting, monitoring and profiling.
  • Takipi - Tells you when and why code breaks in production.
  • Tracer - Manages custom trace identifiers and carries them through distributed systems.
  • YourKit - Fully featured, easy to use, low overhead profiler.
  • Zipkin - A distributed tracing system gather timing data for disparate services developed by Twitter.

Runtimes

Tools for managing jvm runtime processes * Capsule - Dead-Simple Packaging and Deployment for JVM Apps. * CRaSH - The shell for the Java Platform. * Drip - Fast JVM launching without the hassle of persistent JVMs. * HotswapAgent - Redefine classes at runtime and skip the redeploy process. * jvmkill - Agent that forcibly terminates the JVM when it is unable to allocate memory or create a thread. * Nailgun - Nailgun is a client, protocol, and server for running Java programs from the command line without incurring the JVM startup overhead.

Virtual Machines

Virtual machines that implement the JVM specification or parts of it. * Avian - Lightweight highly portable JVM with an option for AOT compilation. * Dalvik - Android runtime (ART) is the managed runtime used by applications and some system services on Android. * DCEVM - Modification of Java HotSwap VM with unlimited support for reloading classes at runtime. * HotSpot - HotSpot virtual machine maintained and distributed by Oracle Corporation. * IBM J9 - JVM developed by IBM. * Eclipse OpenJ9 - Eclipse OpenJ9. * J2ObjC - Translator from Java source to Objective-C code. Keeps shared code between iOS native apps and Android native apps. * jvm.go - A JVM written in Go. * ParparVM - An Open Source Java bytecode to C translator for iOS native development. Designed as a part of the Codename One WORA for mobile project. * MobiDevelop's RoboVM Fork - Ahead of time compiler for JVM bytecode targeting iOS, Mac OSX and Linux. * Zing - The only JVM that eliminates Java garbage collection pauses for large heap sizes. * Zulu - The only certified multi-platform build of OpenJDK: Free, 100% open source Java.

Resources

Documentation

Documentation related to JVM * TCP Tracepoints Linux bcc/BPF using tcplife by Brendan Gregg * Linux tracing workshop - JVM monitoring with BPF, examples and hands-on labs for Linux tracing tools workshops. * JVM Anatomy Park - mini-post series where every post goes deep for only a single topic by Aleksey Shipilёv. * Coordinated Omission problem - Discussion on Mechanical Sympathy. * False sharing - Threads impact the performance of each other while modifying independent variables sharing the same cache line. Martin Thompson. * The JVM specification - The Java Virtual Machine Specification Java SE 8 Edition. * The Java Memory Model - Starting point for discussions of and information concerning the Java Memory Model. * The JSR-133 Cookbook for Compiler Writers - Unofficial guide to implementing the new Java Memory Model (JMM) specified by JSR-133. * Garbage Collection Tuning Guide - HotSpot Virtual Machine Garbage Collection Tuning Guide. * Safepoints - Where is my safepoint? Nitsan Wakart. * Topics in High-Performance Messaging - Design decisions, experience and constraints explained in high performance messaging systems. * Top 10 Performance Mistakes - Digest of the top 10 performance related mistakes Martin Thompson has seen in production. * The USE method - The Utilization Saturation and Errors (USE) Method is a methodology for analyzing the performance of any system. Brendan Gregg. * An introduction to distributed systems - Kyle Kingsbury (author of Jepsen). * Using JDK 9 Memory Order Modes - For expert programmers familiar with Java concurrency, but unfamiliar with the memory order modes available in JDK 9 provided by VarHandles. * CPU Utilization is Wrong - Measure instructions per cycle (IPC) for CPU utilization. Brendan Gregg. * Linux Load Averages: Solving the Mystery - Brendan Gregg. * What every programmer should know about solid-state drives - Emmanuel Goossaert. * Quick Tips for Fast Code on the JVM - Daniel Spiewak.

Communities

Active discussions.

Media

Videos, podcasts and other media related to JVMs * FOSDEM 2018 - FOSDEM 2018 Free Java devroom. * JFokus 2018 - The GC edition. Shenandoah, ZGC, Zing, Fibers, Falcon etc. * G1 Garbage Collector in Java 8/9 - Kirk Pepperdine. * Extreme Profiling: Digging Into Hotspots - Nitsan Wakart. * Java vs. C Performance - Cliff Click. * Why JNI is slow? - Cliff Click * A Crash Course in Modern Hardware - Cliff Click * Java Profiling from the Ground Up - Nitsan Wakart. * The Illusion of Execution - Nitsan Wakart. * Mythbusting Modern Hardware to Gain 'Mechanical Sympathy' - Martin Thompson. * Designing for Performance - Martin Thompson. * How NOT to Measure Latency - Gil Tene. * JVM Language Summit 2015 - JVM Language Summit 2015. * JVM Language Summit 2016 - JVM Language Summit 2016. * JVM Language Summit 2017 - JVM Language Summit 2017. * Bits of advice for VM writers - Cliff Click. * Understanding Java garbage collection ... - Gil Tene. * Faster Object Arrays - Gil Tene at GOTO Conferences. * Java Memory Model Pragmatics - Aleksey Shipilev. * With GC Solved, What Else Makes a JVM Pause? - John Cuthbertson. * JVM Mechanics - Douglas Hawkins. * Give me 15 minutes and I'll change your view of Linux tracing - Brendan Gregg. * Kernel Recipes 2017: Performance Analysis with BPF - Brendan Gregg. * Shenandoah deep talk - Aleksey Shipilëv slightly-deeper-than-usual Shenandoah talk from Virtual Machine Meetup 2017. * Shenandoah: The Garbage Collector That Could - Aleksey Shipilev - Devoxx 2017/11 * Analyzing and Debugging the Java HotSpot VM at the OS Level - Volker Simonis. * Cliff Click podcast 2017/09/16 - Programming and Performance Intro. * Cliff Click podcast 2017/09/16 - Bugs and Coding Styles. * Cliff Click podcast 2017/09/18 - Java vs C/C++. * Cliff Click podcast 2017/09/21 - Debugging Data Races. * Cliff Click podcast 2017/09/24 - Fast Bytecodes for Funny Languages. * Cliff Click podcast 2017/09/28 - Struct of Arrays vs Array of Structs. * Cliff Click podcast 2017/10/04 - The 3 Hardest Problems in Programming. * Cliff Click podcast 2017/11/05 - Modern Hardware Performance and Cache Lines. * Cliff Click podcast 2017/11/09 - Queuing In Practice. * Which technique do programming language parsers and interpreters use? - Cliff Click. * Everything about Stack Traces and Heap Dumps - Andrei Pangin. * Fast and safe production monitoring of JVM with BPF tools - Sasha Goldshtein. * The Future of the Linux Page Cache - Matthew Wilcox.

People

People that share hard-earned, often undocumented, knowledge and data of the inner workings of the JVM * Aleksey Shipilëv - Developing Oracle/Open JDK/Hotspot and other Java-related technologies. * Andrey Breslav - Lead Language Designer of Kotlin @ JetBrains. * Brian Goetz - Java Language Architect at Oracle. * Ben Christensen - Facebook, Netflix, Apple engineering. * Brendan Gregg - Cloud performance, kernel engineer, speaker, author. * Charles Nutter - JRuby guy. * Claes Redestad - Working with OpenJDK stuff @ Oracle. * Cliff Click - Creator of the HotSpot Server Compiler. * Dave Dice - Senior research scientist in the Scalable Synchronization Research Group within Oracle. * Dávid Karnok - RxJava committer that blogs about advanced RxJava. * Doug Lea - Author of the Java memory model. * Gil Tene - Azul Systems. * Heinz Kabutz - Author of 250+ Java Specialists' Newsletters. * Ivan Krylov - JVM expert. * Jake Wharton - Square, Google, open source hacker. * John Rose - HotSpot developer. * Jonas Bonér - Founder & CTO of Lightbend. * Lukas Eder - Blogger. Author of JOOQ. * Marcus Lagergren - Java language team alumnus. * Mark Reinhold - Chief Architect, Java Platform Group, Oracle. * Martin Thompson - Pasty faced performance gangster. * Martijn Verburg - Java Champion. * Kirk Pepperdine - Working in high performance and distributed computing for nearly 20 years. * Nitsan Wakart - Azul Systems. * Norman Maurer - Netty developer. * Paul Phillips - Forever undisputed SLOC Scala compiler dev. * Per Liden - Hacking on the HotSpot JVM at Oracle. * Peter Lawrey - Innovative developer of high performance Java systems for competitive advantage. * Rafael Winterhalter - Author of ByteBuddy. * Richard Warburton - Developer, Speaker, Author. * Richard Startin - Performance Analyst, developer, blogger. * Ron Pressler - Parallel Universe. Leading Fibers and Continuations for the JVM. * Stephen Colebourne - Java Champion. Occasional blogger and speaker. Best known for Joda projects and JSR-310. * Todd L. Montgomery - Ex-CTO, Ex-NASA researcher, network geek, messaging middleware designer. * Stéphane Maldini - Project Reactor Lead @Pivotal. * Stuart Marks - Doctor Deprecator. Java/JDK/OpenJDK developer * Vladimir Ivanov - hacking HotSpot JVM @ Oracle. * Viktor Klang - Deputy CTO at Typesafe Inc.

Contributing

Contributions are very welcome!

Please have a look at contributing.md for guidelines.