Awesome C++

A curated list of awesome C++ (or C) frameworks, libraries, resources, and shiny things. Inspired by awesome-... stuff.

• Awesome C++
  • Standard Libraries
  • Frameworks
  • Artificial Intelligence
  • Asynchronous Event Loop
  • Audio
  • Biology
  • BitTorrent
  • Chemistry
  • CLI
  • Compression
  • Concurrency
  • Configuration
  • Containers
  • Cryptography
  • CSV
  • Database
  • Data visualization
  • Debug
  • Font
  • Game Engine
  • GUI
  • Graphics
  • Image Processing
  • Internationalization
  • Inter-process communication
  • JSON
  • Logging
  • Machine Learning
  • Math
  • Memory Allocation
  • Multimedia
  • Networking
  • PDF
  • Physics
  • Reflection
  • Regular Expression
  • Robotics
  • Scientific Computing
  • Scripting
  • Serialization
  • Sorting
  • Video
  • Virtual Machines
  • Web Application Framework
  • XML
  • Yaml
  • Miscellaneous
• Software
  • Compiler
  • Online Compiler
  • Debugger
  • Integrated Development Environment
  • Build Systems
  • Static Code Analysis
  • Coding Style Tools
• Resources
  • API Design
  • Articles
  • Books
  • Coding Style
  • Podcasts
  • Talks
  • Videos
  • Websites
• Other Awesome Lists
• Contributing

Standard Libraries

C++ Standard Library - including STL Containers, STL Algorithm, STL Functional, etc.

• C++ Standard Library - A collection of classes and functions, which are written in the core language and part of the C++ ISO Standard itself.
• Standard Template Library - The Standard Template Library (STL).
• C POSIX library - A specification of a C standard library for POSIX systems.
• ISO C++ Standards Committee - ISO/IEC JTC1/SC22/WG21 - The C++ Standards Committee. website
• The GNU C Library - The purpose of this manual is to tell you how to use the facilities of the GNU C Library.

Frameworks

C++ generic frameworks and libraries.

• abseil-cpp - Abseil C++ Common Libraries. [Apache2]
• Apache C++ Standard Library - STDCXX, A collection of algorithms, containers, iterators, and other fundamental components. [retired] [Apache2]
• APR - Apache Portable Runtime. Another library of cross-platform utility functions. [Apache2]
• ASL - Adobe Source Libraries provides peer-reviewed and portable C++ source libraries. [MIT]
• Boost ⚡ - A large collection of generic C++ libraries. [Boost] website
• BDE - The BDE Development Environment from Bloomberg Labs. [Apache2]
• C++ Workflow - C++ Parallel Computing and Asynchronous Networking Engine. [Apache2]
• Cinder - A community-developed, free and open source library for professional-quality creative coding. [BSD]
• Coost - A tiny boost library in C++11. [MIT]
• Cxxomfort - A small, header-only library that backports various facilities from more recent C++ Standards to C++03 and later. [MIT]
• Dlib ⚡ - A toolkit for making real world machine learning and data analysis applications in C++ [Boost] website
• EASTL - Electronic Arts Standard Template Library. [BSD]
• ETL - Embedded Template Library. [MIT]
• ffead-cpp - Framework for Enterprise Application Development. [Apache2]
• Folly - An open-source C++ library developed and used at Facebook. [Apache2]
• FunctionalPlus - Functional Programming Library for C++. Write concise and readable C++ code. [MIT]
• GLib - GLib provides the core application building blocks for libraries and applications written in C. [LGPL]
• JUCE - An all-encompassing C++ class library for developing cross-platform software. [Core-Module: ISC, Rest: GPL2/GPL3/Commercial] website
• Kigs framework - A free and open source C++ modular multi-purpose cross platform RAD framework. [MIT] website
• libPhenom - libPhenom is an eventing framework for building high performance and high scalability systems in C. [Apache2]
• LibSourcey - C++11 evented IO for real-time video streaming and high performance networking applications. [LGPL]
• LibU - A multiplatform utility library written in C. [BSD]
• Loki - A C++ library of designs, containing flexible implementations of common design patterns and idioms. [MIT]
• MiLi - Minimal headers-only C++ Library. [Boost]
• OpenFrameworks - A cross platform open source toolkit for creative coding in C++. [MIT] website
• Qt ⚡ - A cross-platform application and UI framework. [GPL/LGPL/Commercial]
• Reason - A cross platform framework designed to bring the ease of use of Java, .Net, or Python to developers who require the performance and strength of C++. [GPL2]
• ROOT - A set of OO frameworks with all the functionality needed to handle and analyze large amounts of data in a very efficient way. Used at CERN. [LGPL]
• Seastar - An advanced, open-source C++ framework for high-performance server applications on modern hardware. [Apache-2.0 License] seastar.io
• STLport - An exemplary version of STL. [Free]
• STXXL - Standard Template Library for Extra Large Data Sets. [Boost]
• tbox - A glib-like multi-platform c library. [Apache2] website
• Ultimate++ - A C++ cross-platform rapid application development framework. [BSD]
• uSTL - The small STL library. [MIT]
• Windows Template Library - A C++ library for developing Windows applications and UI components. [Public]
• Yomm2 - Fast, Orthogonal, Open multi-methods. Supersedes Yomm11 [Boost]

Artificial Intelligence

• ANNetGPGPU - A GPU (CUDA) based Artificial Neural Network library. [LGPL]
• btsk - Game Behavior Tree Starter Kit. [zlib]
• Evolving Objects - A template-based, ANSI-C++ evolutionary computation library which helps you to write your own stochastic optimization algorithms insanely fast. [LGPL]
• frugally-deep - Header-only library for using Keras models in C++. [MIT]
• Genann - Simple neural network library in C. [zlib]
• MXNet - Lightweight, Portable, Flexible Distributed/Mobile Deep Learning with Dynamic, Mutation-aware Dataflow Dep Scheduler; for Python, R, Julia, Scala, Go, Javascript and more website
• PyTorch - Tensors and Dynamic neural networks in Python with strong GPU acceleration. website
• flashlight - Flashlight is a fast, flexible machine learning library written entirely in C++. [BSD]
• Recast/Detour - (3D) Navigation mesh generator and pathfinder, mostly for games. [zlib]
• TensorFlow - An open source software library for numerical computation using data flow graphs [Apache]
• oneDNN - An open-source cross-platform performance library for deep learning applications. [Apache] website
• CNTK - Microsoft Cognitive Toolkit (CNTK), an open source deep-learning toolkit. [Boost]
• tiny-dnn - A header only, dependency-free deep learning framework in C++11. [BSD]
• Veles - Distributed platform for rapid Deep learning application development. [Apache]
• Kaldi - Toolkit for speech recognition. [Apache]

Asynchronous Event Loop

• Asio - A cross-platform C++ library for network and low-level I/O programming that provides developers with a consistent asynchronous model using a modern C++ approach. [Boost] website
• Boost.Asio - A cross-platform C++ library for network and low-level I/O programming. [Boost]
• C++ Actor Framework - An Open Source Implementation of the Actor Model in C++. [BSD-3-Clause] website
• Ichor - An event queue which focuses on thread safety and provides dependency injection. [MIT]
• libev - A full-featured and high-performance event loop that is loosely modelled after libevent, but without its limitations and bugs. [BSD and GPL]
• libevent - An event notification library. [BSD]
• libhv - Cross-platform event loop library. [BSD]
• libuv - Cross-platform asynchronous I/O. [BSD]
• promise-cpp - Header only library that implements Promise/A+ standard. [Anti-996]
• uvw - C++ wrapper for libuv. [MIT]

Audio

Audio, Sound, Music, Digitized Voice Libraries

• AudioFile - A simple C++ library for reading and writing audio files. [GPL3]
• dr_libs - Single file audio decoding libraries for C and C++. [Unlicense]
• FMOD - An easy to use crossplatform audio engine and audio content creation tool for games. [Free for non-commercial/Commercial]
• KFR - Fast, modern C++ DSP framework, FFT, FIR/IIR filters, Sample Rate Conversion. [GPL/Commercial]
• LAME - LAME is a high quality MPEG Audio Layer III (MP3) encoder. [LGPL]
• libsndfile - C library with C++ wrapper for reading and writing files containing sampled sound through one standard library interface. [LGPL-2.1] website
• libsoundio - C library for cross-platform real-time audio input and output. [MIT] website
• Maximilian - C++ Audio and Music DSP Library. [MIT]
• OpenAL - Open Audio Library - A crossplatform audio API. [BSD/LGPL/Commercial]
• miniaudio - Single file audio playback and capture library. [Unlicense] website
• ni-media - C++ library for reading and writing audio files. [MIT]
• Opus - A totally open, royalty-free, highly versatile audio codec. [BSD]
• PortAudio - PortAudio is a free, cross-platform, open-source, audio I/O library. [MIT]
• rnnoise - Recurrent neural network for audio noise reduction. [BSD-3-Clause]
• SELA - SimplE Lossless Audio. [MIT]
• SoLoud - Easy, portable audio engine for games. [zlib]
• Speex - A free codec for free speech. Obsoleted by Opus. [BSD]
• Tonic - Easy and efficient audio synthesis in C++. [Unlicense]
• Vorbis - Ogg Vorbis is a fully open, non-proprietary, patent-and-royalty-free, general-purpose compressed audio format. [BSD]
• minimp3 - Public domain, header-only MP3 decoder with clean-room implementation. [CC0]
• Verovio - Verovio is a fast and lightweight music notation engraving library. [LGPL] website
• Wav2Letter++ - Public domain, a fast open source speech processing toolkit written entirely in C++ and uses the ArrayFire tensor library and the flashlight machine learning library for maximum efficiency [BSD]

Biology

Bioinformatics, Genomics, Biotech

• BioC++ - C++ Computational Libraries for Bioinformatics. [BSD]
• Chaste - An open source C++ library for the computational simulation of mathematical models developed for physiology and biology. [BSD]
• libsequence - A C++ library for representing and analyzing population genetics data. [GPL]
• SeqAn - Algorithms and data structures for the analysis of sequences with the focus on biological data. [BSD/3-clause]
• Vcflib - A C++ library for parsing and manipulating VCF files. [MIT]
• Wham - Structural variants (SVs) in Genomes by directly applying association tests to BAM files. [MIT]

BitTorrent

• jech/dht - BitTorrent DHT library in C. [MIT]
• libtorrent (a.k.a. libtorrent-rasterbar) - An efficient feature complete C++ bittorrent implementation. [BSD]
• LibTorrent (a.k.a. libtorrent-rakshasa) - BitTorrent library. [GPL]
• libutp - uTorrent Transport Protocol library. [MIT]

Chemistry

Chemistry, Quantum Chemistry, Solid-State Chemistry/Physics, Geochemistry, Biochemistry

• d-SEAMS - A molecular dynamics trajectory analysis engine in C++ and Lua with Nix. It is an acronym for Deferred Structural Elucidation Analysis for Molecular Simulations. [GPL] website
• gromacs - A message-passing parallel molecular dynamics implementation. [GPL] website
• Reaktoro - A computational framework in C++ and Python for modeling chemically reactive systems. [LGPL] website
• LAMMPS - A classical molecular dynamics code with a focus on materials modeling. It's an acronym for Large-scale Atomic/Molecular Massively Parallel Simulator. [GPL] website
• MADNESS - Multiresolution Adaptive Numerical Environment for Scientific Simulation. [GPL] website
• MPQC - The Massively Parallel Quantum Chemistry program, MPQC, computes properties of atoms and molecules from first principles using the time independent Schrödinger equation. [GPL] website
• ORCA - An ab initio quantum chemistry program package that contains modern electronic structure methods. [Academic] website
• Psi - An ab initio computational chemistry package. [GPL] website

CLI

Console/Terminal User Interface, Command Line Interface

• Argh! - A minimalist, frustration-free, header-only argument handler. [BSD]
• Taywee/args - A simple header-only C++ argument parser library. [MIT]
• Boost.Program_options - A library to obtain program options via conventional methods such as command line and config file. [Boost]
• Clara - A simple to use, composable, command line parser for C++ 11 and beyond. [BSL-1.0]
• cli - A cross-platform header only C++14 library for interactive command line interfaces (Cisco style). [Boost]
• CLI11 - Header only single or multi-file C++11 library for simple and advanced CLI parsing. [BSD]
• jarro2783/cxxopts - Lightweight C++ command line option parser. [MIT]
• docopt.cpp - A library to generate option parser from docstring. [MIT/Boost]
• FINAL CUT - Library for creating terminal applications with text-based widgets. [LGPL]
• gflags - Commandline flags module for C++. [BSD]
• indicators - Activity indicators for Modern C++. [MIT]
• linenoise - A small self-contained alternative to readline and libedit. [BSD-2-Clause]
• linenoise-ng - A small, portable GNU readline replacement for Linux, Windows and MacOS which is capable of handling UTF-8 characters. [BSD]
• Lyra - A simple to use, composable, command line parser for C++ 11 and beyond. [Boost]
• Ncurses - A terminal user interface. [MIT]
• oof - Convenient, high-performance RGB color and position control for console output. [MIT]
• PDCurses - Public domain curses library with both source code and pre-compiled library available. [PublicDomain]
• popl - A single-header templated command line arguments and ini file parser for C++ 11 and beyond. [MIT]
• replxx - A readline and libedit replacement that supports UTF-8, syntax highlighting, hints, works on Unix and Windows. [BSD]
• tabulate - Table Maker for Modern C++ [MIT]
• TCLAP - A mature, stable and feature-rich library for defining and accessing command line arguments in ANSI C++. [MIT]
• termbox - A C library for writing text-based user interfaces. [MIT]
• cpp-terminal - Small header only C++ library for writing multiplatform terminal applications. [MIT]
• FTXUI - C++ Functional Terminal User Interface. [MIT]
• imtui - Immediate Mode Text-based User Interface [MIT]

Compression

Compression and Archiving Libraries

• bit7z - A C++ static library offering a clean and simple interface to the 7-zip DLLs. [GPLv2]
• Brotli - Brotli compression format. Developed by Google. [MIT]
• bzip2 - A freely available, patent free, high-quality data compressor. [BSD]
• bzip3 - A better and stronger spiritual successor to BZip2. [LGPL]
• FiniteStateEntropy - New generation entropy codecs : Finite State Entropy and Huff0.
• PhysicsFS - A library to provide abstract access to various archives. It is intended for use in video games, and the design was somewhat inspired by Quake 3's file subsystem. [zlib]
• KArchive - A library for creating, reading, writing and manipulating file archives like zip and tar. It also provides transparent compression and decompression of data, using formats like gzip, via a subclass of QIODevice. [LGPL]
• libarchive - Multi-format archive and compression library. [New BSD] website
• LZ4 - Extremely Fast Compression algorithm. [BSD] website
• LZFSE - LZFSE compression library and command line tool. Developed by Apple.
• LZHAM - Lossless data compression library with a compression ratio similar to LZMA but with much faster decompression. [BSD]
• LZMA ⚡ - The default and general compression method of 7z format. [PublicDomain]
• LZMAT - An extremely fast real-time lossless data compression library. [GPL]
• miniz - Single C source file Deflate/Inflate compression library with zlib-compatible API, ZIP archive reading/writing, PNG writing. [MIT]
• Minizip - Zlib with latest bug fixes that supports PKWARE disk spanning, AES encryption, and IO buffering. [zlib]
• smaz - Small strings compression library. [BSD]
• Snappy - A fast compressor/decompressor. [BSD]
• ZLib - A very compact compression library for data streams. [zlib]
• zlib-ng - zlib for the "next generation" systems. Drop-In replacement with some serious optimizations. [zlib]
• zstd - Zstandard - Fast real-time compression algorithm. Developed by Facebook. [BSD]
• ZZIPlib - Provides read access on ZIP-archives. [MPL/LGPL]

Concurrency

Concurrency and Multithreading

• alpaka - Abstraction library for parallel kernel acceleration. [LGPLv3+]
• ArrayFire - A general purpose GPU library. [BSD]
• Async++ - A lightweight concurrency framework for C++11, inspired by the Microsoft PPL library and the N3428 C++ standard proposal. [MIT]
• Boost.Compute - A C++ GPU Computing Library for OpenCL. [Boost]
• Bolt - A C++ template library optimized for GPUs. [Apache2]
• ck - Concurrency primitives, safe memory reclamation mechanisms and non-blocking data structures. [BSD]
• concurrentqueue - A fast multi-producer, multi-consumer lock-free concurrent queue for C++11. [BSD,Boost]
• Cpp-Taskflow - Fast C++ Parallel Programming with Task Dependencies. [MIT]
• CUB - CUB provides state-of-the-art, reusable software components for every layer of the CUDA programming mode. [New BSD]
• cuda-api-wrappers - Lightweight, Modern-C++ wrappers for the CUDA GPU programming runtime API. [BSD]
• cupla - C++ API to run CUDA/C++ on OpenMP, Threads, TBB, ... through Alpaka. [LGPLv3+]
• C++React - A reactive programming library for C++11. [Boost]
• FiberTaskingLib - Task-based multi-threading library that supports task graphs with arbitrary dependencies. [Apache]
• HPX - A general purpose C++ runtime system for parallel and distributed applications of any scale. [Boost]
• Intel Games Task Scheduler - A task scheduling framework designed for the needs of game developers. [MIT]
• Intel Parallel STL - Intel® implementation of C++17 STL for C++11 and above. [Apache2]
• Intel TBB - Intel® Threading Building Blocks. [Apache2]
• junction - A library of concurrent data structures in C++. [BSD]
• Kokkos - A performance portable programming model for parallel execution and memory abstraction. [BSD]
• libcds - A C++ library of Concurrent Data Structures. [BSD]
• Libclsph - An OpenCL based GPU accelerated SPH fluid simulation library. [MIT]
• libdill - Introduces structured concurrency in C. [MIT]
• libdispatch - Grand Central Dispatch (GCD), developed by Apple Inc., is a task parallelism technology based on the thread pool pattern. libdispatch is a library that provides the implementation of GCD's services. [Apache-2.0] website
• libmill - Introduces Go-style concurrency in C. [MIT]
• marl - Marl is a hybrid thread / fiber task scheduler written in C++ 11. [Apache-2.0]
• moderngpu - moderngpu is a productivity library for general-purpose computing on GPUs. It is a header-only C++ library written for CUDA. The unique value of the library is in its accelerated primitives for solving irregularly parallel problems. [FreeBSD & Copyright, Sean Baxter]
• NCCL - Optimized primitives for collective multi-GPU communication. [BSD]
• OpenCL - The open standard for parallel programming of heterogeneous systems.
• OpenMP - The OpenMP API.
• rotor - Event loop friendly C++ actor micro framework. [MIT]
• SObjectizer - An implementation of Actor, Publish-Subscribe, and CSP models in one rather small C++ framework. [BSD-3-Clause]
• Quantum - A powerful C++ coroutine dispatcher framework built on top of boost::coroutines2.
• RaftLib - The RaftLib C++ library, streaming/dataflow concurrency via C++ iostream-like operators [Apache2]
• readerwriterqueue - A fast single-producer, single-consumer lock-free queue for C++. [BSD]
• stdgpu - Efficient STL-like Data Structures on the GPU. [Apache2]
• Thrust - A parallel algorithms library which resembles the C++ Standard Template Library (STL). [Apache2]
• transwarp - A header-only C++ library for task concurrency. [MIT]
• VexCL - A C++ vector expression template library for OpenCL/CUDA. [MIT]
• STAPL - A C++ parallel programming framework designed to work on both shared and distributed memory parallel computers. [BSD]
• concurrencpp - A general concurrency library containing tasks, executors, timers and C++20 coroutines to rule them all.

Configuration

Configuration files, INI files

• inifile-cpp - A header-only and easy to use Ini file parser for C++. [MIT]
• inih - Simple .INI file parser in C, good for embedded systems. [BSD-3-Clause]
• inih - Single header only C++ version of inih. [BSD-3-Clause]
• iniparser - INI file parser. [MIT]
• libconfig - C, C++ library for processing structured configuration files. [LGPL-2.1] website
• libconfuse - Small configuration file parser library for C. [ISC]
• simpleini - Cross-platform C++ library providing a simple API to read and write INI-style configuration files. [MIT]
• toml++ - Header-only TOML parser and serializer for C++17 and later. [MIT] website

Containers

• C++ B-tree - A template library that implements ordered in-memory containers based on a B-tree data structure. [Apache2]
• Colony - An unordered "bag"-type container which outperforms std containers in high-modification scenarios while maintaining permanent pointers to non-erased elements regardless of insertion/erasure. [zLib] website
• dynamic_bitset - A C++17 header-only dynamic bitset. [MIT]
• Forest - Template library implementing an AVL, a Binary Search, a KD and a Quad Tree. [MIT]
• Hashmaps - Implementation of open addressing hash table algorithms in C++. [MIT]
• Hopscotch map - A fast header-only hash map which uses hopscotch hashing for collisions resolution. [MIT]
• LSHBOX - A c++ toolbox of locality-sensitive hashing (LSH), provides several popular LSH algorithms, also support Python and MATLAB. [GPL]
• PGM-index - A data structure that enables fast lookup, predecessor, range searches and updates in arrays of billions of items using orders of magnitude less space than traditional indexes. [Apache2] website
• plf::list - A std::list implementation which removes range splicing in order to enable cache-friendlier structure, yielding significant performance gains. [zLib] website
• plf::stack - A replacement container for the std::stack container adaptor, with better performance than any std container in a stack context. [zLib] website
• ring_span lite - A simplified implementation of Arthur O'Dwyer's ring_span implementation ie. a circular buffer view. [MIT]
• robin-hood-hashing - Fast & memory efficient hashtable based on robin hood hashing for C++14. [MIT]
• robin-map - Fast hash map and hash set using robin hood hashing. [MIT]
• sparsepp - A fast, memory efficient hash map for C++. [BSD 3-clause]

Cryptography

Cryptography and Encryption Libraries

• Bcrypt - A cross platform file encryption utility. Encrypted files are portable across all supported operating systems and processors. [BSD]
• BeeCrypt - A portable and fast cryptography library. [LGPLv2.1+]
• Botan - A crypto library for C++. [BSD-2]
• Crypto++ - A free C++ class library of cryptographic schemes. [Boost] website
• digestpp - C++11 header-only message digest (hash) library. [PublicDomain]
• GnuPG - A complete and free implementation of the OpenPGP standard. [GPL]
• GnuTLS - A secure communications library implementing the SSL, TLS and DTLS protocols. [LGPL2.1]
• Libgcrypt - A general purpose cryptographic library originally based on code from GnuPG. [LGPLv2.1+]
• LibreSSL - A free version of the SSL/TLS protocol forked from OpenSSL in 2014. [?]
• libsodium - P(ortable|ackageable) NaCl-based crypto library, opinionated and easy to use. [ISC]
• libhydrogen - A lightweight, secure, easy-to-use crypto library suitable for constrained environments. [ISC]
• LibTomCrypt - A fairly comprehensive, modular and portable cryptographic toolkit. [WTFPL]
• mbedTLS - An open source, portable, easy to use, readable and flexible SSL library, previously known as PolarSSL. [Apache2] website
• Nettle - A low-level cryptographic library. [LGPL]
• OpenSSL - A robust, commercial-grade, full-featured, and Open Source cryptography library. [Apache] website
• retter - A collection of hash functions, ciphers, tools, libraries, and materials related to cryptography.
• s2n - An implementation of the TLS/SSL protocols. [Apache]
• sha1collisiondetection - Library and command line tool to detect SHA-1 collision in a file. [MIT]
• Tink - A multi-language, cross-platform library that provides cryptographic APIs that are secure, easy to use correctly, and hard(er) to misuse. [Apache-2.0]
• Tiny AES in C - Small portable AES128/192/256 in C. [PublicDomain]
• Themis - crypto library for painless data security, providing symmetric and asymmetric encryption, secure sockets with forward secrecy, for mobile and server platforms. [Apache2]

CSV

Libraries for parsing Comma Separated Value (CSV) files

• csv2 - Fast CSV parser for modern C++. [MIT]
• Csv::Parser - Compile-time and runtime CSV parser written in C++17. [Zlib]
• Fast C++ CSV Parser - Small, easy-to-use and fast header-only library for reading CSV files. [BSD-3-Clause]
• lazycsv - A fast, lightweight and single-header csv parser for modern C++. [MIT]
• Vince's CSV Parser - A fast, self-contained, streaming C++17 CSV parser with optional type-casting and statistics. [MIT]

Database

Database Libraries, SQL Servers, ODBC Drivers, and Tools

• ClickHouse - C++ client for ClickHouse DBMS. [Apache2]
• hiberlite - C++ Object-relational mapping for sqlite3. [BSD]
• Hiredis - A minimalistic C client library for the Redis database. [BSD]
• LevelDB - A fast key-value storage library written at Google that provides an ordered mapping from string keys to string values. [BSD]
• LMDB - Very fast embedded key/value store with full ACID semantics. [OpenLDAP]
• LMDB++ - C++11 wrapper for the LMDB embedded database library. [PublicDomain]
• MongoDB C Driver - MongoDB client library for C. [Apache2]
• MongoDB C++ Driver - C++ driver for MongoDB. [Apache2]
• MongoDB Libbson - A BSON utility library. [Apache2]
• MySQL++ - A C++ wrapper for MySQL's C API. [LGPL]
• nanodbc - A small C++ wrapper for the native C ODBC API. [MIT]
• ODB - An open-source, cross-platform, and cross-database object-relational mapping (ORM) system for C++. [GPLv2]
• redis3m - Wrapper of hiredis with clean C++ interface, supporting sentinel and ready to use patterns. [Apache2]
• RocksDB - Embedded key-value store for fast storage from facebook. [BSD]
• SimDB - High performance, shared memory, lock free, cross platform, single file, minimal dependencies, C++11 key-value store [Apache2]
• SOCI - A database abstraction layer for C++. [BSL-1.0]
• SQLite - A completely embedded, full-featured relational database in a few 100k that you can include right into your project. [PublicDomain]
• SQLiteC++ - SQLiteC++ (SQLiteCpp) is a smart and easy to use C++ SQLite3 wrapper. [MIT]
• sqlite_modern_cpp - Header only C++14 wrapper around sqlite library. [MIT]
• sqlite_orm - SQLite ORM light header only library for modern C++. [AGPL + paid MIT]
• sqlpp11 - A type safe embedded domain specific language for SQL queries and results in C++. [BSD-2-Clause]
• TileDB - Fast Dense and Sparse Multidimensional Array DBMS. [MIT] website
• UnQLite - A self-contained, serverless, zero-configuration, transactional NoSQL engine. [BSD-2-Clause] website
• upscaledb - An embedded "typed" key/value store with a built-in query interface. [GPLv3]

Data visualization

Data visiualization Libraries

• matplotplusplus - C++ Graphics Library for Data Visualization. [MIT] website

Debug

Debugging Libraries, Memory Leak and Resource Leak Detection, Unit Testing

• backward-cpp - A beautiful stack trace pretty printer for C++. [MIT]
• benchmark - Google provided small microbenchmark support library. [Apache2]
• Boost.Test - Boost Test Library. [Boost]
• check - Check is a unit testing framework for C. [LGPL-2.1] website
• doctest - The lightest feature rich C++ single header testing framework. [MIT]
• Catch2 - A modern, C++-native, header-only, test framework for unit-tests, TDD and BDD. [BSL-1.0]
• Celero - C++ Benchmarking Framework. [Apache2]
• CppUTest - Unit testing and mocking framework for C/C++. [BSD-3-clause]
• CUTE - C++ Unit Testing Easier. [LGPL3]
• CMocka - unit testing framework for C with support for mock objects. [Apache2]
• CppUnit - C++ port of JUnit. [LGPL2]
• CTest - The CMake test driver program. [BSD]
• dbg-macro - A dbg(…) macro for C++. [MIT]
• DebugViewPP - Debug logging viewer. [BSL]
• Deleaker - A tool for resource leak detection, including memory, GDI and handle leaks.
• FakeIt - Simple mocking framework for C++. [MIT]
• fff - A micro-framework for creating fake C functions. [MIT]
• Google Mock - A library for writing and using C++ mock classes. [BSD]
• Google Test - Google C++ Testing Framework. [BSD]
• ig-debugheap - Multiplatform debug heap useful for tracking down memory errors. [BSD]
• libtap - Write tests in C. [GPL2]
• microprofile - Profiler with web-view for multiple platforms. [Unlicense]
• MinUnit - A minimal unit testing framework for C self-contained in a single header file. [MIT]
• Mockator - Eclipse CDT plug-in for C++ Seams and Mock Objects.
• nanobench - Simple, fast, accurate single-header microbenchmarking functionality for C++11/14/17/20. [MIT] website
• Nanotimer - A simple low-overhead cross-platform timer class for benchmarking. [zLib] website
• Nonius - A C++ micro-benchmarking framework. [CC]
• Remotery - Single C File Profiler with Web Viewer. [Apache2]
• Touca - Open-source regression testing system that you can self-host. [Apache2] website
• UnitTest++ - A lightweight unit testing framework for C++. [MIT/X Consortium license]
• Unity - Simple Unit Testing for C. [MIT]
• utest.h - Single header unit testing framework for C and C++. [Unlicense]
• μt - C++20 single header/single module, macro-free μ(micro)/Unit Testing Framework [Boost]
• VLD - Visual Leak Detector. A free, robust, open-source memory leak detection system for Visual C++.

Font

Libraries for parsing and manipulating font files.

• Fontconfig - Font configuration and customization library. [MIT] website
• FreeType - FreeType is a freely available software library to render fonts. [FTL & GPLv2]
• otfcc - A C library and utility used for parsing and writing OpenType font files. [Apache-2.0]

Game Engine

• Acid - A high speed C++17 Vulkan game engine. [MIT]
• Allegro - A cross-platform library mainly aimed for video games and multimedia programming. [zlib]
• Cocos2d-x - A multi-platform framework for building 2d games, interactive books, demos and other graphical applications. [MIT]
• Corange - A game engine written in pure C, SDL and OpenGL. [BSD]
• crown - Crown is a general purpose data-driven game engine, written from scratch in orthodox C++ with a minimalistic and data-oriented design philosophy in mind. [MIT]
• delta3d - A robust simulation platform. [LGPL2]
• EnTT - Gaming meets modern C++. [MIT]
• GamePlay - A cross-platform native C++ game framework for creating 2D/3D mobile and desktop games. [Apache2]
• Godot - A fully featured, open source, MIT licensed, game engine. [MIT]
• Grit - Community project to build a free game engine for implementing open world 3D games. [MIT]
• Halley - A lightweight game engine written in C++14 with a "true" entity-component system. [Apache 2.0]
• KlayGE - a cross-platform open source game engine with plugin-based architecture. [GPLv2] website
• nCine - A cross-platform 2D game engine with an emphasis on performance, written in C++11 and optionally scriptable in Lua. [MIT] website
• o3de - An open-source, real-time, multi-platform 3D engine based on Amazon Lumberyard. [Apache2] website
• OpenXRay - a community-modified X-Ray engine used in S.T.A.L.K.E.R. game series. [Modified BSD/non-commercial only]
• Oxygine - A cross-platform 2D C++ game engine. [MIT]
• Panda3D - A game engine, a framework for 3D rendering and game development for Python and C++ programs. [Modified BSD] website
• PixelGameEngine - The official distribution of olcPixelGameEngine, a tool used in javidx9's YouTube videos and projects. [OLC3]
• Polycode - A cross-platform framework for creative code in C++ (with Lua bindings). [MIT] website
• raylib - A simple and easy-to-use library to enjoy videogames programming. [zlib/libpng] website
• Spring - A powerful free cross-platform RTS game engine. [GPLv2/GPLv3] website
• Torque2D - An open-source and cross-platform C++ engine built for 2D game development. [MIT] website
• Torque3D - An open-source C++ engine built for 3D game development. [MIT] website
• toy engine - toy is a thin and modular c++ game engine and offers simple expressive c++ idioms to design full featured 2D or 3D games in fast iterations.
• Urho3D - A free lightweight, cross-platform 2D and 3D game engine implemented in C++. Greatly inspired by OGRE and Horde3D. [MIT]

GUI

Graphic User Interface

• Boden - Native, mobile, cross-platform GUI Framework. [GPL/LGPL/Commercial] website
• CEGUI - Flexible, cross-platform GUI library.
• Elements - Lightweight, fine-grained, resolution independent, modular GUI library. [MIT]
• FLTK - Fast, light, cross-platform C++ GUI toolkit. [GPL2]
• GacUI - GPU Accelerated C++ User Interface, with WYSIWYG developing tools, XML supports, built-in data binding and MVVM features. [Ms-PL]
• GTK+ - A multi-platform toolkit for creating graphical user interfaces. [LGPL]
• gtkmm - The official C++ interface for the popular GUI library GTK+. [LGPL]
• imgui - Immediate Mode Graphical User Interface with minimal dependencies. [MIT]
• implot - Immediate Mode Plotting widgets for imgui. [MIT]
• iup - Multi-platform toolkit for building graphical user interfaces. [MIT]
• libui - Simple and portable (but not inflexible) GUI library in C that uses the native GUI technologies of each platform it supports. [MIT]
• MyGUI - Fast, flexible and simple GUI. [MIT]
• nana - Nana is a cross-platform library for GUI programming in modern C++ style. [Boost]
• NanoGui - A minimalistic cross-platform widget library for OpenGL 3.x or higher. [BSD]
• nuklear - A single-header ANSI C gui library. [PublicDomain]
• QCustomPlot - Qt plotting widget without further dependencies. [GPLv3]
• Qwt - Qt Widgets for Technical Applications. [Own based on LGPL]
• QwtPlot3D - A feature-rich Qt/OpenGL-based C++ programming library, providing essentially a bunch of 3D-widgets. [zlib]
• RmlUi - The HTML/CSS User Interface library evolved. Fork of libRocket. [MIT]
• Sciter - Sciter is an embeddable HTML/CSS/scripting engine aimed to be used as an UI layer of modern desktop applications. [Free/Commercial]
• Slint - Lightweight GUI toolkit for desktop and embedded. [GPL/Free/Commercial] website
• wxWidgets - A C++ library that lets developers create applications for Windows, Mac OS X, Linux and other platforms with a single code base. [Own LGPL]
• xtd - Modern C++17/20 framework to create console (CLI), forms (GUI like WinForms) and tunit (unit tests like Microsoft Unit Testing Framework) applications on Windows, macOS, Linux, iOS and android. [MIT]
• Yue - A library for creating native cross-platform GUI apps. [LGPLv2]

Graphics

• assimp - Open Asset Import Library (assimp) is a cross-platform 3D model import library which aims to provide a common API for different 3D asset file formats. [BSD-3-Clause] website
• bgfx - A cross-platform rendering library. [BSD]
• Blend2D - 2D vector graphics engine powered by a JIT compiler. [Zlib] website
• bs::framework - Modern C++14 library for the development of real-time graphical applications. [MIT]
• Cairo - A 2D graphics library with support for multiple output devices. [LGPL2 or Mozilla MPL]
• C-Turtle - A C++11 header-only turtle graphics library acting as a CImg wrapper. [MIT]
• Diligent Engine - A modern cross-platform low-level 3D graphics library. [Apache2]
• DirectXTK - A collection of helper classes for writing DirectX 11.x code in C++. [MIT]
• GLFW - A simple, cross-platform OpenGL wrangling library. [zlib/libpng]
• Harfang 3D 3D visualization library usable in C++, Python, Lua and Go. Based on BGFX. [GPLv3/LGPLv3/Commercial] website
• herebedragons - A basic 3D scene implemented with various engines, frameworks or APIs. [MIT] website
• Horde3D - A small 3D rendering and animation engine. [EPL]
• Ion - A small and efficient set of libraries for building cross-platform client or server applications that use 3D graphics. [Apache2] website
• Irrlicht - A high performance realtime 3D engine written in C++. [zlib]
• libigl - Simple C++ geometry processing library. [MPL2]
• LLGL - Low Level Graphics Library (LLGL) is a thin abstraction layer for the modern graphics APIs. [BSD-3-Clause]
• magnum - Lightweight and modular C++11/C++14 graphics middleware for games and data visualization. [MIT] website
• NanoVG - Antialiased 2D vector drawing library on top of OpenGL for UI and visualizations. [Zlib]
• Ogre 3D ⚡ - A scene-oriented, real-time, flexible 3D rendering engine (as opposed to a game engine) written in C++. [MIT]
• OpenSceneGraph - An open source high performance 3D graphics toolkit. [OSGPL]
• OpenSubdiv - Pixar's library for evaluating and rendering subdivision surfaces on CPU and GPU. [Modified Apache2]
• OpenVDB - Library and tools for storing, editing, and rendering volumetric datasets. [MPL2]
• Panda3D - A framework for 3D rendering and game development for Python and C++. [BSD]
• Partio - Library for wrangling particle data, with support for most common file formats. [Modified BSD]
• Skia - A complete 2D graphic library for drawing Text, Geometries, and Images. [BSD] website
• TinySpline - A small, yet powerful ANSI C library for interpolating, transforming, and querying arbitrary NURBS, B-Splines, and Bézier curves. [MIT]
• urho3d - Cross-platform rendering and game engine. [Many different, mostly MIT]
• Yocto/GL - Tiny C++ Libraries for Data-Driven Physically-based Graphics. [MIT]

Image Processing

• Boost.GIL - Generic Image Library.
• CImg - A small, open source, C++ toolkit for image processing. [Own LGPL or GPL]
• CxImage - An image processing and conversion library to load, save, display, transform BMP, JPEG, GIF, PNG, TIFF, MNG, ICO, PCX, TGA, WMF, WBMP, JBG, J2K images. [zlib]
• Dlib ⚡ - A modern C++11 machine learning, computer vision, numerical optimization, and deep learning toolkit. [Boost] website
• FreeImage - An open source library that supports popular graphics image formats and others as needed by today's multimedia applications. [GPL2 or GPL3]
• GD - GD Graphics Library, famously used in PHP for image loading/manipulation & thumbnail generation. [custom permissive license, requires mention in user docs] website
• DCMTK - DICOM Toolkit.
• GDCM - Grassroots DICOM library.
• ITK - An open-source, cross-platform system for image analysis. [Apache2 from ITK 4.0]
• Leptonica - Leptonica is an open source library containing software that is broadly useful for image processing and image analysis applications. [BSD-2-Clause] website
• libfacedetection - Open source library for face detection in images. The face detection speed can reach 1500FPS. [BSD]
• libjpeg-turbo - A JPEG image codec that uses SIMD instructions to accelerate baseline JPEG encoding and decoding. [IJG & BSD-3-Clause & zlib] website
• libvips - A fast image processing library with low memory needs. [LGPL] website
• Magick++ - ImageMagick program interfaces for C++. [Apache2]
• MagickWnd - ImageMagick program interfaces for C. [Apache2]
• OpenCV ⚡ - Open source computer vision. [BSD]
• OpenEXR - Cross-platform library for high dynamic range imaging. [Modified BSDF]
• OpenImageIO - Powerful image and texture wrangling library with support for a wide number of common lossy and RAW formats. [Modified BSD]
• SAIL - Easy-to-use cross-platform image decoding library with pluggable image codecs. [MIT]
• Simd - C++ image processing library with using of SIMD: SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2, AVX-512, VMX(Altivec) and VSX(Power7), NEON for ARM. [MIT]
• stb-image - STB single-header image loading library. [Public Domain]
• tesseract-ocr - An OCR engine. [Apache2]
• TinyEXIF - Tiny ISO-compliant C++ EXIF and XMP parsing library for JPEG. [MIT]
• Video++ - A C++14 high performance video and image processing library. [MIT]
• VIGRA - A generic C++ computer vision library for image analysis. [MIT X11]
• VTK - Open-source, freely available software system for 3D computer graphics, image processing and visualization. [BSD]

Internationalization

• gettext - GNU 'gettext'. [GPL2]
• IBM ICU - A set of C/C++ and Java libraries providing Unicode and Globalization support. [ICU]
• libiconv - An encoding conversion library between different character encodings. [GPL]
• utf8.h - Single header utf8 string functions for C and C++. [Unlicense]
• utf8proc - A clean C library for processing UTF-8 Unicode data. [MIT]

Inter-process communication

• Apache Thrift - Efficient cross-language IPC/RPC, works between C++, Java, Python, PHP, C#, and many more other languages. Originally developed by Facebook. [Apache2]
• Boost.Interprocess - Header-only Boost library that supports kernel-level shared memory and memory-mapped files, with in-built synchronization mechanisms (semaphores, mutexes, and more). [Boost] website
• Cap'n Proto - Fast data interchange format and capability-based RPC system. [MIT] website
• eCAL - Pub/sub, client/server, C++/Python/C#, various message protocols (protobuf, capnproto ..). [Apache2] website
• gRPC - A high performance, open source, general-purpose RPC framework. [BSD] website
• Ice - Comprehensive RPC framework with support for C++, C#, Java, JavaScript, Python and more. [GPLv2]
• iceoryx - True zero-copy inter-process communication framework for safety critical systems with bindings for C, Rust. Runs on Linux, QNX, Windows, Mac OS, FreeBSD. [Apache2] website
• libjson-rpc-cpp - JSON-RPC framework for C++ servers and clients. [MIT]
• nanomsg - A simple high-performance implementation of several "scalability protocols". [MIT] website
• nng - nanomsg-next-generation, a light-weight brokerless messaging library. [MIT] website
• rpclib - A modern C++ msgpack-RPC server and client library. [MIT]
• simple-rpc-cpp - A simple RPC wrapper generator to C/C++ functions. [BSD]
• WAMP - Provides RPC and pub/sub messaging patterns. (various implementations, various languages)
• xmlrpc-c - A lightweight RPC library based on XML and HTTP. [BSD]

JSON

• Boost.PropertyTree - A property tree parser/generator that can be used to parse XML/JSON/INI/Info files. [Boost]
• cJSON - Ultralightweight JSON parser in ANSI C. [MIT]
• frozen - JSON parser and generator for C/C++. [GPL & GPL2]
• Glaze - Extremely fast, in memory, JSON and interface library for modern C++. [MIT]
• Jansson - C library for encoding, decoding and manipulating JSON data. [MIT]
• jbson - jbson is a library for building & iterating BSON data, and JSON documents in C++14. [Boost]
• JeayeSON - A very sane (header only) C++ JSON library. [BSD]
• Jsmn - A minimalistic JSON parser in C. [MIT]
• json ⚡ - JSON for Modern C++. [MIT]
• JSON++ - A JSON parser in C++. [MIT]
• json.h - A simple one header/one source solution to parsing JSON in C and C++. [Unlicense]
• json-build - C89 tiny zero-allocation JSON serializer. [MIT]
• json-c - A JSON implementation in C. [MIT]
• jsoncons - A C++ header-only library for JSON and JSON-like binary formats with JSONPointer, JSONPatch, JSONPath and JMESPath. [Boost]
• JsonCpp - A C++ library for interacting with JSON. [MIT]
• json-parser - Very low footprint JSON parser written in portable ANSI C. [BSD]
• json11 - A tiny JSON library for C++11. [MIT]
• json-struct - High performance, single header JSON parser parsing to and from C++ structs. [MIT]
• json-voorhees - JSON library for C++. Support for C++11. No dependencies, fast and dev-friendly. [Apache2]
• jute - Very simple C++ JSON Parser. [PublicDomain]
• libjson - A JSON parser and printer library in C. easy to integrate with any model. [LGPL]
• libjson - Lightweight JSON library. [?]
• LIBUCL ⚡ - Universal configuration library parser [BSD-2-Clause]
• parson - Parson is a lighweight json library written in C. [MIT]
• PicoJSON - A header-file-only, JSON parser serializer in C++. [BSD]
• qt-json - A simple class for parsing JSON data into a QVariant hierarchy and vice versa. [GPLv3]
• QJson - A qt-based library that maps JSON data to QVariant objects. [LGPL2]
• RapidJSON ⚡ - A fast JSON parser/generator for C++ with both SAX/DOM style API. [MIT]
• sajson - Lightweight, extremely high-performance JSON parser for C++11. [MIT]
• simdjson - Extremely fast JSON library that can parse gigabytes of JSON per second. [Apache-2.0]
• taoJSON - Zero-dependency C++ header-only JSON library. [MIT]
• ujson - µjson is a a small, C++11, UTF-8, JSON library. [MIT]
• YAJL - A fast streaming JSON parsing library in C. [ISC]
• yyjson - A high performance JSON library written in ANSI C. [MIT]

Logging

• Blackhole - Attribute-based logging framework, which is designed to be fast, modular and highly customizable. [MIT]
• Boost.Log - Designed to be very modular and extensible. [Boost]
• Easylogging++ - Extremely light-weight high performance logging library for C++11 (or higher) applications. [MIT]
• fmtlog - A performant fmtlib-style logging library with latency in nanoseconds. [MIT]
• G3log - Asynchronous logger with Dynamic Sinks. [PublicDomain]
• glog - C++ implementation of the Google logging module.
• Log4cpp - A library of C++ classes for flexible logging to files, syslog, IDSA and other destinations. [LGPL]
• log4cplus - A simple to use C++ logging API providing thread-safe, flexible, and arbitrarily granular control over log management and configuration. [BSD & Apache2]
• loguru - A lightweight C++ logging library. [PublicDomain]
• plog - Portable and simple log for C++ in less than 1000 lines of code. [MPL2]
• reckless - Low-latency, high-throughput, asynchronous logging library for C++. [MIT]
• spdlog - Super fast, header only, C++ logging library.
• templog - A very small and lightweight C++ library which you can use to add logging to your C++ applications. [Boost]
• P7Baical - An open source and cross-platform library for high-speed sending telemetry & trace data with minimal usage of CPU and memory. [LGPL]
• Quill - Asynchronous cross platform low latency logging library. [MIT]

Machine Learning

• Caffe - A fast framework for neural networks. [BSD]
• CCV - C-based/Cached/Core Computer Vision Library, A Modern Computer Vision Library. [BSD]
• darknet - Open source neural network framework written in C and CUDA. [PublicDomain] website
• Dlib ⚡ - A modern C++11 machine learning, computer vision, numerical optimization, and deep learning toolkit. [Boost] website
• Fido - A highly-modular C++ machine learning library for embedded electronics and robotics. [MIT] website
• flashlight - A fast, flexible machine learning library from Facebook AI Research written entirely in C++ and based on the ArrayFire tensor library. [BSD-3-Clause] website
• libsvm - A simple, easy-to-use, efficient library for Support Vector Machines. [BSD-3-Clause] website
• m2cgen - A CLI tool to transpile trained classic ML models into a native C code with zero dependencies. [MIT]
• MeTA - A modern C++ data sciences toolkit. [MIT] website
• Minerva - A fast and flexible system for deep learning. [Apache2]
• mlpack - A scalable c++ machine learning library. [LGPLv3] website
• OpenCV ⚡ - Open Source Computer Vision Library. [BSD] website
• oneDAL - A powerful machine learning library that helps speed up big data analysis. [Apache]
• ONNX runtime - C and C++ library for training and inference ONNX models. ONNX is a standard that AI models can be converted into, regardless of the library they are trained with. [MIT] website
• Recommender - C library for product recommendations/suggestions using collaborative filtering (CF). [BSD]
• RNNLIB - RNNLIB is a recurrent neural network library for sequence learning problems. [GPLv3]
• SHOGUN - The Shogun Machine Learning Toolbox. [GPLv3]
• sofia-ml - The suite of fast incremental algorithms for machine learning. [Apache2]
• VLFeat - The VLFeat open source library implements popular computer vision algorithms specialising in image understanding and local featurexs extraction and matching. [BSD-2-Clause] website
• xgboost - Scalable, Portable and Distributed Gradient Boosting (GBDT, GBRT or GBM) Library, for Python, R, Java, Scala, C++ and more. Runs on single machine, Hadoop, Spark, Flink and DataFlow. [Apache2]
• ncnn - A high-performance neural network inference computing framework optimized for mobile platforms. [BSD]

Math

• Apophenia - A C library for statistical and scientific computing [GPL2]
• Armadillo - Fast C++ library for linear algebra & scientific computing. [Apache2] website
• autodiff - A modern, fast and expressive C++ library for automatic differentiation. [MIT] website
• blaze - high-performance C++ math library for dense and sparse arithmetic. [BSD]
• Boost.Multiprecision - provides higher-range/precision integer, rational and floating-point types in C++, header-only or with GMP/MPFR/LibTomMath backends. [Boost]
• ceres-solver - C++ library for modeling and solving large complicated nonlinear least squares problems from google. [BSD]
• CGAL - Collection of efficient and reliable geometric algorithms. [LGPL&GPL] website
• cml - free C++ math library for games and graphics. [Boost]
• CNL - A Compositional Numeric Library for C++. [Boost]
• CXXGraph - free C++(17) graph header-only library for representation and algorithms execution. [AGPL-3.0]
• Dlib ⚡ - A modern C++11 machine learning, computer vision, numerical optimization, and deep learning toolkit. [Boost] website
• Eigen - A high-level C++ library of template headers for linear algebra, matrix and vector operations, numerical solvers and related algorithms. [MPL2]
• ExprTK - The C++ Mathematical Expression Toolkit Library (ExprTk) is a simple to use, easy to integrate and extremely efficient run-time mathematical expression parser and evaluation engine. [MIT]
• Geometric Tools - C++ library for computing in the fields of mathematics, graphics, image analysis and physics. [Boost] website
• GLM - Header-only C++ math library that matches and inter-operates with OpenGL's GLSL math. [MIT] website
• GMTL - Graphics Math Template Library is a collection of tools implementing Graphics primitives in generalized ways. [GPL2]
• GMP - A C library for arbitrary precision arithmetic, operating on signed integers, rational numbers, and floating-point numbers. [LGPL3 & GPL2]
• Klein - A fast, SIMD-optimized C++17 Geometric Algebra library for point, line, and plane projections, intersections, joins, rigid-body motion, and more. [MIT] website
• linalg.h - Single header, public domain, short vector math library for C++. [Unlicense]
• MIRACL - A Multiprecision Integer and Rational Arithmetic Cryptographic Library. [AGPL]
• NumCpp - A templatized header only C++ implementation of the Python Numpy library. [MIT]
• muparser - muParser is an extensible high performance math expression parser library written in C++. [MIT]
• LibTomMath - A free open source portable number theoretic multiple-precision integer library written entirely in C. [PublicDomain & WTFPL] website
• linmath.h - A lean linear math library, aimed at graphics programming. [WTFPL]
• lp_solve - A library used to formulate and solve linear programming problems. [LGPL] website
• OpenBLAS - An optimized BLAS library based on GotoBLAS2 1.13 BSD version. [BSD 3-clause] website
• PCG-rand - PCG is a family of simple fast space-efficient statistically good algorithms for random number generation. Unlike many general-purpose RNGs, they are also hard to predict. [Apache]
• QuantLib - A free/open-source library for quantitative finance. [Modified BSD] website
• StatsLib - A C++ header-only library of statistical distribution functions. [Apache2] website
• SymEngine - Fast symbolic manipulation library, a rewriting of SymPy's core in C++. [MIT]
• TinyExpr - A C library for parsing and evaluating math expressions from strings. [zlib]
• Vc - SIMD Vector Classes for C++. [BSD]
• Versor - A (fast) Generic C++ library for Geometric Algebras, including Euclidean, Projective, Conformal, Spacetime (etc).
• Wykobi - A C++ library of efficient, robust and simple to use C++ 2D/3D oriented computational geometry routines. [MIT]
• xtensor - A C++14 library for numerical analysis with multi-dimensional array expressions, inspired by NumPy syntax. [BSD 3-clause] website
• universal - A C++14 header-only library implementing arbitrary posit arithmetic. The posit number system is a tapered floating point that is more efficient than IEEE floating point. Posits enable reproducible computational science. [MIT license] website

Memory Allocation

• Boehm GC - Conservative garbage collector for C and C++. [similar to X11] website
• C Smart Pointers - Smart pointers for the (GNU) C programming language. [MIT]
• Hoard - Fast, Scalable, and Memory-efficient Malloc for Linux, Windows, and Mac. [GPL, commercial] website
• jemalloc - General purpose malloc(3) implementation that emphasizes fragmentation avoidance and scalable concurrency support. [BSD] website
• memory - STL compatible C++ memory allocator library. [ZLib]
• memory-allocators - Custom memory allocators to improve the performance of dynamic memory allocation. [MIT]
• mimalloc - A compact general purpose allocator with excellent performance. [MIT]
• rpmalloc - Cross platform lock free thread caching 16-byte aligned memory allocator implemented in C. [PublicDomain]
• snmalloc - Message passing based high-performance allocator. [MIT]
• TCMalloc - Google's fast, multi-threaded malloc implementation. [Apache-2.0] website
• tgc - A tiny garbage collector for C written in ~500 LOC. [BSD]

Multimedia

• GStreamer - A library for constructing graphs of media-handling components. [LGPL]
• libass - Portable subtitle renderer for the ASS/SSA subtitle format. [ISC]
• libav - A collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata. [LGPL v2.1+ and others] website
• LIVE555 Streaming Media - Multimedia streaming library using open standard protocols (RTP/RTCP, RTSP, SIP). [LGPL]
• libVLC - libVLC (VLC SDK) media framework. [GPL]
• MediaInfoLib - Convenient unified display of the most relevant technical and tag data for video and audio files. [BSD]
• QtAv - A multimedia playback framework based on Qt and FFmpeg to write a player easily. [LGPL] website
• SDL ⚡ - Simple DirectMedia Layer. [zlib]
• SFML ⚡ - Simple and Fast Multimedia Library. [zlib] website
• TagLib - A library for reading and editing the metadata of several popular audio formats. [LGPL/MPL] website

Networking

• ACE - An OO Network Programming Toolkit in C++. [?MIT?]
• Boost.Asio ⚡ - A cross-platform C++ library for network and low-level I/O programming. [Boost]
• Boost.Beast ⚡ - HTTP and WebSocket built on Boost.Asio in C++11. [BSL-1.0] website
• Breep - Event based, high-level C++14 peer-to-peer library. [EUPL-1.1 (OSI approved)]
• C++ REST SDK - C++ REST SDK (previously named Casablanca). [Apache2]
• Restbed - C++11 Asynchronous RESTful framework. [AGPL]
• Restinio - A header-only C++14 library that gives you an embedded HTTP/Websocket server. [BSD]
• c-ares - A C library for asynchronous DNS requests. [MIT]
• cpp-httplib - A single file C++11 header-only HTTP/HTTPS server library. [MIT]
• cpp-netlib - A collection of open-source libraries for high level network programming. [Boost]
• cpp-netlib/uri - URI parser/builder library for C++, compatible with RFC 3986 and RFC 3987. [BSL-1.0]
• CppServer - Ultra fast and low latency asynchronous socket server & client C++ library with support TCP, SSL, UDP, HTTP, HTTPS, WebSocket protocols and 10K connections problem solution. [MIT]
• cpr - A modern C++ HTTP requests library with a simple but powerful interface. Modeled after the Python Requests module. [MIT] website
• curlcpp - An object oriented C++ wrapper for CURL(libcurl). [MIT]
• DPDK - Data Plane Development Kit, libraries and drivers for fast packet processing. [BSD-3-Clause & GPL-2.0] website
• Dyad.c - Asynchronous networking for C. [MIT]
• ENet - Reliable UDP networking library. [MIT] website
• evpp - C++ high performance networking with TCP/UDP/HTTP protocols. [BSD]
• H2O - An optimized HTTP server with support for HTTP/1.x and HTTP/2. It can also be used as a library. [MIT]
• HTTP Parser ⚡ - A http request/response parser for C. [MIT]
• KCP - A fast and reliable ARQ protocol that helps applications to reduce network latency. [MIT]
• libcurl - Multiprotocol file transfer library. [MIT/X derivate license]
• libhttpserver - C++ library for creating an embedded Rest HTTP server (and more). [LGPL2.1]
• Libmicrohttpd - GNU libmicrohttpd is a small C library that is supposed to make it easy to run an HTTP server as part of another application. [LGPL v2.1+]
• libpcap - A portable C/C++ library for network traffic capture. [BSD] website
• libquic - A QUIC protocol library extracted from Chromium's QUIC Implementation. [BSD]
• librdkafka - Apache Kafka client library for C and C++. [BSD-2-Clause]
• libwebsockets - A lightweight pure C WebSocket implementation that provides both client and server libraries. [LGPL2.1 + static link exception] website
• lwIP - A lightweight TCP/IP stack. [Modified BSD]
• Mongoose - Extremely lightweight webserver. [GPL2]
• MQTT-C - A portable MQTT C client for embedded systems and PCs alike. [MIT] website
• mTCP - Highly scalable user-level TCP stack for multicore systems. [Modified BSD]
• Muduo - A C++ non-blocking network library for multi-threaded server in Linux. [BSD]
• nghttp2 - HTTP/2 C Library. [MIT] website
• Onion - HTTP server library in C designed to be lightweight and easy to use. [Apache2/GPL2]
• PF_RING™ - High-speed packet processing framework. [LGPL-2.1] website
• PicoHTTPParser - A tiny, primitive, fast HTTP request/response parser. [MIT]
• POCO ⚡ - C++ class libraries and frameworks for building network- and internet-based applications that run on desktop, server, mobile and embedded systems. [Boost] website
• Proxygen - Facebook's collection of C++ HTTP libraries including an easy to use HTTP server. [BSD]
• RakNet - A cross platform, open source, C++ networking engine for game programmers. [BSD]
• restclient-cpp - Simple REST client for C++. It wraps libcurl for HTTP requests. [MIT]
• Seasocks - Simple, small, C++ embeddable webserver with WebSockets support. [BSD]
• Silicon - A high performance, middleware oriented C++14 http web framework. [MIT]
• tlse - Single C file TLS 1.2/1.3 implementation, using tomcrypt as crypto library [BSD-2-Clause]
• Tufão - An asynchronous web framework for C++ built on top of Qt. [LGPL2]
• uriparser - Strictly RFC 3986 compliant URI parsing and handling library. [BSD-3-Clause]
• uWebSockets - µWS is one of the most lightweight, efficient & scalable WebSocket & HTTP server implementations available. [Zlib]
• WAFer - A C language-based ultra-light software platform for scalable server-side and networking applications. Think node.js for C programmers. [GPL2]
• Wangle - A client/server application framework to build asynchronous, event-driven modern C++ services. [Apache-2.0]
• wdt - An embeddedable library (and command line tool) aiming to transfer data between 2 systems as fast as possible over multiple TCP paths. [BSD-3-Clause]
• WebSocket++ - C++/Boost Asio based websocket client/server library. [BSD]
• PcapPlusPlus - a multiplatform C++ network sniffing and packet parsing and crafting framework. [Unlicense]
• ZeroMQ - High-speed, modular asynchronous communication library. [LGPL] website

PDF

Libraries for parsing and manipulating PDF documents.

• libharu - A free, cross platform, open-sourced software library for generating PDF. [zlib]
• litePDF - Library to create and edit PDF documents that uses GDI functions through a device context to draw the page content. [LGPL v3 and zlib]
• MuPDF - A lightweight PDF, XPS, and E-book viewer. [AGPL/Commercial]
• PoDoFo - A library to work with the PDF file format. [LGPL]
• Poppler - Open-source multi-backend PDF rendering library based on the xpdf-3.0 code base. [GPLv2/GPLv3]
• Xpdf - Xpdf is a free PDF viewer and toolkit, including a text extractor, image converter, HTML converter, and more. [GPL v2/GPL v3]
• DynaPDF - An easy-to-use PDF generation library. [Commercial]

Physics

Dynamics simulation engines

• Box2D - A 2D physics engine for games. [BSD-like]
• Bullet - A 3D physics engine for games. [zlib] website
• Chipmunk - A fast and lightweight 2D game physics library. [MIT] website
• LiquidFun - A 2D physics engine for games. [BSD-like]
• Newton Dynamics - An integrated solution for real time simulation of physics environments. [zlib]
• ODE - Open Dynamics Engine - An open source, high performance library for simulating rigid body dynamics. [BSD&LGPL]
• Kratos - framework for building parallel, multi-disciplinary simulation software, aiming at modularity, extensibility, and high performance. [BSD] website
• ofxBox2d - openFrameworks wrapper for Box2D. [BSD-like]
• PhysX - An open-source realtime physics engine middleware SDK developed by Nvidia as a part of Nvidia GameWorks software suite. [BSD-3-Clause]
• Project Chrono - An open source multi-physics simulation engine. [BSD-3-Clause] website
• Quantum++ - A modern C++11 quantum computing library. [MIT]
• Simbody - High-performance C++ multibody dynamics/physics library for simulating articulated biomechanical and mechanical systems like vehicles, robots, and the human skeleton. [Apache2]
• SOFA - SOFA is an open-source framework targeting at real-time simulation, with an emphasis on medical simulation. [LGPL] website

Reflection

• config-loader - A C++17 static reflection framework, from parse configuration file to native data structure. [MIT]
• Better Enums - Reflective enums (to string, iteration). Single header. [BSD] website
• clReflect - C++ Reflection using clang. [MIT]
• CPFG - A C++03 library for reflection, callback and script binding. [Apache2] website
• CPP-Reflection - C++ Reflection using clang. [MIT]
• Magic Enum - Header-only C++17 library provides static reflection for enums (to string, from string, iteration), work with any enum type without any macro or boilerplate code. [MIT]
• magic_get - std::tuple like methods for user defined types without any macro or boilerplate code. [Boost]
• meta - Header-only, non-intrusive and macro-free runtime reflection system in C++. [MIT]
• Nameof - Header-only C++17 library provides nameof macros and functions to obtain the simple name of variable, type, function, macro, and enum. [MIT]
• Ponder - A C++11 library for reflection. [MIT]
• RTTR - A C++11 library for reflection. [MIT] website
• visit_struct - A miniature library for struct-field reflection in C++. [BSL-1.0]
• Refureku - A C++17 runtime reflection and code generation library. [MIT]

Regular Expression

• CppVerbalExpressions - C++ regular expressions made easy. [MIT]
• CTRE - A Compile time PCRE (almost) compatible regular expression matcher. [MIT]
• Hyperscan - Hyperscan is a high-performance multiple regex matching library by Intel. Provides simultaneous matching of large numbers of regexps (up to tens of thousands). Typically used in a DPI library stack. [BSD]
• Oniguruma - A modern and flexible regular expressions library that supports a variety of character encodings. [BSD]
• PCRE - A regular expression C library inspired by the regular expression capabilities in Perl. [BSD]
• PIRE - Perl Incompatible Regular Expressions library by Yandex. Can be really fast (more than 400 MB/s). [LPGL v3.0]
• RE2 - A software library for regular expressions via a finite-state machine using automata theory. [BSD-3-Clause]
• SLRE - Super Light Regexp engine for C/C++. [GPLv2/Commercial]
• sregex - A non-backtracking NFA/DFA-based Perl-compatible regex engine library for matching on large data streams. [BSD]

Robotics

• MOOS-IvP - A set of open source C++ modules for providing autonomy on robotic platforms, in particular autonomous marine vehicles.
• MRPT - Mobile Robot Programming Toolkit. [BSD]
• PCL - Point Cloud Library is a standalone, large scale, open project for 2D/3D image and point cloud processing [BSD] website
• Robotics Library (RL) - A self-contained C++ library for robot kinematics, motion planning and control. [BSD]
• RobWork - A collection of C++ libraries for simulation and control of robot systems. [Apache2] website
• ROS - Robot Operating System provides libraries and tools to help software developers create robot applications. [BSD]
• YARP (Yet Another Robot Platform) - Library and toolkit for communication and device interfaces. [BSD-3-Clause] website

Scientific Computing

• AMGCL - a header-only C++ library for solving large sparse linear systems with algebraic multigrid. [MIT]
• FFTW - A C library for computing the DFT in one or more dimensions. [GPL]
• GSL - GNU scientific library. [GPL]
• preCICE - Coupling library for partitioned multi-physics simulations (FSI, CHT, and more). [LGPL] website
• TileDB - Fast Dense and Sparse Multidimensional Array DBMS. [MIT] website
• Trilinos - High performance PDE solvers. [BSD]
• Torch - A scientific computing framework with wide support for machine learning algorithms that puts GPUs first. [BSD-3-Clause] website

Scripting

• AngelScript - AngelScript is a game-oriented interpreted/compiled scripting language. [zlib]
• Boost.Python - A C++ library which enables seamless interoperability between C++ and the Python programming language. [Boost]
• cppimport - Import C++ files directly from Python! [MIT]
• CppSharp - Tools and libraries to glue C/C++ APIs to high-level languages. [MIT]
• ChaiScript - An easy to use embedded scripting language for C++. [BSD] website
• ctypes.sh - A foreign function interface for bash. [MIT]
• Cython - Cython is an optimising static compiler for both the Python programming language and the extended Cython programming language (based on Pyrex). It makes writing C extensions for Python as easy as Python itself. [Apache] website
• djinni - A tool for generating cross-language type declarations and interface bindings. [Apache2]
• Duktape - An embeddable Javascript engine with compact footprint. [MIT] website
• JavaCpp - The missing bridge between Java and native C++. [Apache2]
• libffi - A portable foreign-function interface library. [MIT] website
• Lua - A minimal and fast scripting engine for configuration files and basic application scripting. [MIT]
• LuaBridge - A lightweight, dependency-free library for binding Lua to C++. [MIT]
• luacxx - C++11 API for creating Lua bindings. [MIT]
• nbind - Magical headers that make your C++ library accessible from JavaScript. [MIT]
• PHP-CPP - A library to build PHP extensions with C++. [Apache2] website
• pybind11 - Seamless operability between C++11 and Python. [BSD]
• SIP - C or C++ Bindings Generator for Python v2 and v3. [GPL]
• sol2 - A C++ <-> Lua API wrapper with advanced features and top notch performance. [MIT]
• SWIG - A wrapper/interface Generator that let you link your c++ code to Javascript, Perl, PHP, Python, Tcl and Ruby. [GPL/Output not licensed] website
• V7 - An embedded JavaScript engine. [GPL2]
• V8 - A fast JavaScript engine by Google that can be embedded into any C++ application. [BSD]
• ChakraCore -A JavaScript engine by Microsoft that can be embedded into nodejs. [MIT]

Serialization

• Bitsery - Header only C++ binary serialization library. [MIT]
• Bond - An open source, cross-platform framework for working with schematized data. [MIT]
• Boost.Serialization - Boost Serialization Library. [Boost]
• Cap'n Proto - Fast data interchange format and capability-based RPC system. [MIT] website
• cereal - A C++11 library for serialization. [BSD]
• cista - A C++17 library for zero-copy high-performance (de-)serialization. [MIT]
• cppcodec - Header-only C++11 library to encode/decode base64, base32 and hex with consistent, flexible API. [MIT]
• FastBinaryEncoding - Fast Binary Encoding is ultra fast and universal serialization solution for C++, C#, Go, Java, JavaScript, Kotlin, Python, Ruby, Swift. [MIT]
• FlatBuffers - A Memory efficient serialization library. [Apache2]
• MessagePack - Efficient binary serialization format "like JSON" for C and C++. [Apache2] website
• mrpt-serialization - Versioned serialization to binary or text formats. [BSD] website
• nanopb - Small code-size Protocol Buffers implementation in ANSI C. [Zlib]
• protobuf - Protocol Buffers - Google's data interchange format. [BSD]
• protobuf-c - Protocol Buffers implementation in C. [BSD]
• SimpleBinaryEncoding - encoding and decoding application messages in binary format for low-latency applications. [Apache2]
• upb - A small protobuf implementation in C. [BSD]
• YAS - Very fast Yet Another Serialization library supports the binary/text/json formats. [Boost]

Sorting

• pdqsort - Pattern-defeating quicksort. [zlib]
• Timsort - A templated stable sorting function which outperforms quicksort-based algorithms including std::sort, for reversed or semi-sorted data. [MIT]
• Indiesort - A sort wrapper which enables the use of std::sort (& other random-access sort functions) with non-random-access containers, and also improves sort performance for large/non-trivially-copyable types in random-access containers and arrays. [zLib] website

Video

• libvpx - VP8/VP9 Codec SDK. [BSD]
• FFmpeg - A complete, cross-platform solution to record, convert and stream audio and video. [LGPL2/GPL2]
• libde265 - Open h.265 video codec implementation. [LGPL] website
• x265 - Open h.265 video codec implementation. [GPL2] website
• OpenH264 - Open Source H.264 Codec. [BSD] website
• Theora - A free and open video compression format. [BSD]
• Vireo - A lightweight and versatile video processing library by Twitter. [MIT]

Virtual Machines

• CarpVM - "interesting" VM in C. Let's see how this goes. [GPLv3]
• MicroPython - Aims to put an implementation of Python 3.x on a microcontroller. [MIT]
• TinyVM - A small, fast, lightweight virtual machine written in pure ANSI C. [MIT]

Web Application Framework

• Civetweb - Provides easy to use, powerful, C/C++ embeddable web server with optional CGI, SSL and Lua support. [MIT]
• C++ REST SDK - Microsoft project for cloud-based client-server communication in native code using a modern asynchronous C++ API design. [MIT]
• CppCMS - A Free High Performance Web Development Framework (not a CMS). [LGPLv3]
• Crow - Crow is a C++ microframework for running web services. It uses routing similar to Python's Flask. [BSD] website
• Cutelyst - A C++ Web Framework built on top of Qt, using the simple approach of Catalyst (Perl) framework. [LGPLv2.1+] website
• Drogon - A C++14/17 based, high-performance HTTP application framework. [MIT]
• facil.io - Evented, high performance C web framework supporting HTTP, WebSockets, SSE and more. [MIT] website
• Kore - ultra fast and flexible web server / framework for web applications developed in C. [ISC]
• libOnion - lightweight library to help you create webservers in C programming language. [LGPLv3]
• lwan - Experimental, scalable, high performance HTTP server. [GPL2]
• oat++ - Light, zero-dependency framework to create high-performance web-services. [Apache-2.0] website
• Pistache - Pistache is a C++ REST framework written in pure C++11 with no external dependency. [Apache2]
• QDjango - A web framework written in C++ and built on top of the Qt library. Where possible it tries to follow django's API, hence its name. [LGPL]
• TreeFrog Framework - High-speed and full-stack web application framework based on C++ and Qt, which supports HTTP and WebSocket protocol (with O/R mapping). [BSD] website
• userver - Asynchronous C++17 framework with a rich set of abstractions and database drivers for fast and comfortable creation of efficient microservices, services and utilities. [Apache-2.0] website
• Wt - A C++ library for developing web applications. [GPL/Commercial]

XML

XML is crap. Really. There are no excuses. XML is nasty to parse for humans, and it's a disaster to parse even for computers. There's just no reason for that horrible crap to exist. - Linus Torvalds

• Boost.PropertyTree - A property tree parser/generator that can be used to parse XML/JSON/INI/Info files. [Boost]
• Expat - An XML parser library written in C. [MIT]
• Libxml2 - The XML C parser and toolkit of Gnome. [MIT]
• libxml++ - An XML Parser for C++. [LGPL2]
• Mini-XML - A small XML parsing library written in ANSI C. [LGPL2 with exceptions]
• PugiXML - A light-weight, simple and fast XML parser for C++ with XPath support. [MIT]
• RapidXml - An attempt to create the fastest XML parser possible, while retaining useability, portability and reasonable W3C compatibility. [Boost]
• TinyXML - A simple, small, minimal, C++ XML parser that can be easily integrating into other programs. [zlib]
• TinyXML2 - A simple, small, efficient, C++ XML parser that can be easily integrating into other programs. [zlib]
• TinyXML++ - A completely new interface to TinyXML that uses MANY of the C++ strengths. Templates, exceptions, and much better error handling. [MIT]
• Xerces-C++ - A validating XML parser written in a portable subset of C++. [Apache2]

Yaml

• mini-yaml - Single header YAML 1.0 C++11 serializer/deserializer. [MIT]
• yaml-cpp - A YAML parser and emitter in C++ [MIT]

Miscellaneous

Useful libraries or tools that don't fit in the categories above or maybe just not categorised yet

• access_profiler - A tool to count accesses to member variables in c++ programs. [GPL3]
• American fuzzy lop a.k.a. afl-fuzz - Crazy fuzzing tool that automatically discovers bugs given time and minimal example input. [Apache2]
• Better String - An alternative to the string library for C which is more functional and does not have buffer overflow overrun problems. Also includes a C++ wrapper. [BSD, GPL2]
• Boost.Signals - An implementation of a managed signals and slots system. [Boost]
• Concord - A Discord API wrapper library written in C. [MIT] website
• CPPItertools - Range-based for loop add-ons inspired by the Python builtins and itertools library. [BSD-2-Clause]
• D++ (DPP) - A lightweight, high performance and scalable C++ library for creating Discord Bots. [Apache2] website
• DynaMix - A library which allows you to compose and modify objects at run time. [MIT]
• fccf - A command-line tool that recursively searches a directory to find C/C++ source code matching a search string. [MIT]
• {fmt} ⚡ - Small, safe and fast formatting library for C++. [Simplified BSD]
• FastFormat - Fast, Safe C++ Formatting inspired by log4j and Pantheios [Simplified BSD]
• casacore - A set of c++ core libraries derived from aips++. [LGPL]
• QtVerbalExpressions - This Qt lib is based off of the C++ VerbalExpressions library. [MIT]
• cxx-prettyprint - A pretty printing library for C++ containers. [Boost]
• icecream-cpp - A small printing library for debugging purposes. [MIT]
• gcc-poison - A simple header file for developers to ban unsafe C/C++ functions from applications.
• Kangaru - A dependency injection container for C++11 and C++14. [MIT]
• Klib - Small and lightweight implementations of common algorithms and data structures. [MIT]
• libsigc++ - A typesafe callback system for standard C++. [LGPL] website
• libcpuid - A small C library for x86 CPU detection and feature extraction. [BSD]
• libevil - The Evil License Manager. [GPLv3]
• libnih - A lightweight library of C functions and structures. [GPL2.1]
• libusb - A universal USB library which allows for portable access to USB devices. [LGPL2]
• Mach7 - A Pattern-matching library for C++. [BSD]
• mio - Cross-platform C++11 header-only library for memory mapped file IO. [MIT]
• PEGTL - The Parsing Expression Grammar Template Library. [MIT]
• Remote Call Framework - Inter-process communication framework for C++. [GPL2/Commercial]
• Scintilla - A free source code editing component. [MIT]
• SDS - Simple Dynamic Strings library for C. [BSD]
• semver.c - A semver parser and render in ANSI C. [MIT]
• Serial Communication Library - Cross-platform, Serial Port library written in C++. [MIT]
• sigslot - C++ Signal/Slot Library. [PublicDomain]
• SimpleSignal - High performance C++11 signals. [PublicDomain]
• Stage - Mobile robot simulator. [GPL2]
• stdman Formatted C++11/14 stdlib man pages (from cppreference). [MIT]
• stb ⚡ - A range of single-file libraries for C/C++. [PublicDomain]
• StrTk - A C++ library consisting of high performance string processing routines. [MIT]
• Tulip Indicators - A C library of over 100 financial technical analysis indicators. [LGPL]
• ub-canaries - A collection of C/C++ programs that try to get compilers to exploit undefined behavior.
• value-category-cheatsheet A PDF cheatsheet for lvalues, rvalues, and the like. [Jank copyleft]
• VarTypes - A feature-rich, object-oriented framework for managing variables in C++ / Qt4. [LGPL]
• ZBar - A barcode scanner library, which allows to scan photos/images/video streams for barcodes and return their value. [LGPL2]
• ZXing - An open-source, multi-format 1D/2D barcode image processing library implemented in Java, with ports to other languages. [Apache]
• pprint - Pretty Printer for Modern C++. [MIT]

Software

Software for creating a development environment.

Compiler

List of C or C++ compilers

• 8cc - A Small C Compiler.
• c - Compile and execute C "scripts" in one go! [MIT]
• Clang - A C compiler for LLVM. Supports C++11/14/1z C11. Developed by LLVM Team. [NCSA]
• GCC - GNU Compiler Collection. Supports C++11/14/1z C11 and OpenMP. [GNU GPL3]
• PCC - A very old C compiler. Supports C99.
• Intel C++ Compiler - Developed by Intel.
• LLVM - Collection of modular and reusable compiler and toolchain technologies.
• Microsoft Visual C++ - MSVC, developed by Microsoft.
• Open WatCom - Watcom C, C++, and Fortran cross compilers and tools. [Sybase Open Watcom Public License]
• Oracle Solaris Studio - C, C++ and Fortran compiler for SPARC and x86. Supports C++11. Available on Linux and Solaris. [OTN Developer License]
• TCC - Tiny C Compiler. [LGPL]

Online Compiler

List of online C or C++ compilers

• codechef - A simple online compiler CodeChef.
• codepad - An online compiler/interpreter, and a simple collaboration tool.
• coliru - Online compiler/shell with support for various C++ compilers.
• Compiler Explorer - An interactive compiler with assembly output available.
• CompileOnline - Compile and Execute C++ online on Linux.
• Ideone - An online compiler and debugging tool which allows you to compile source code and execute it online in more than 60 programming languages.
• repl.it - A powerful yet simple tools and platforms for educators, learners, and developers.
• Rextester - Online compiler which provides several compilers(Clang, GCC, MSVC) and several editors.
• Try It Online - TIO is a family of online interpreters for an evergrowing list of practical and recreational programming languages.
• Wandbox - An online Clang/GCC compiler with Boost available.
• paiza.io - An online C/C++ compiler with multiple files supporting feature, Github(gist) integration and collaborative editing.
• InterviewBit - A simple and easy to use online C++ compiler.

Debugger

List of C or C++ debuggers

• Comparison of debuggers - A list of Debuggers from Wikipedia.
• GDB - GNU Debugger.
• LLDB - The LLDB Debugger.
• Metashell - An interactive template metaprogramming shell which includes the MDB metadebugger.
• Valgrind - A tool for memory debugging, memory leak detection, and profiling.
• x64dbg - An open-source x64/x32 debugger for windows.

Integrated Development Environment

List of C or C++ nominal IDEs.

• Anjuta DevStudio - The GNOME IDE. [GPL3]
• AppCode - an IDE for Objective-C, C, C++, and JavaScript development built on JetBrains’ IntelliJ IDEA platform.
• Cevelop - Cross-platform C and C++ IDE based on Eclipse CDT with additional plug-ins.
• CLion - Cross-platform C and C++ IDE from JetBrains.
• Code::Blocks - A free C, C++ and Fortran IDE.
• CodeLite - Another cross-plaform, free C and C++ IDE. [GPL2 with an exception for plugins]
• color_coded - A vim plugin for libclang-based highlighting. [MIT]
• Dev-C++ - A portable C/C++/C++11 IDE.
• Eclipse CDT - A fully functional C and C++ IDE based on the Eclipse platform.
• Geany - Small, fast, cross-platform IDE. [GPL]
• IBM VisualAge - A family of computer integrated development environments from IBM.
• Irony-mode - A C/C++ minor mode for Emacs powered by libclang.
• juCi++ - Cross-platform, lightweight C++ IDE with libclang integration. [MIT]
• KDevelop - A free, open source IDE.
• Microsoft Visual Studio - An IDE from Microsoft.
• Microsoft Visual Studio Code ⚡ - An open-source IDE from Microsoft. [MIT]
• NetBeans - An IDE for developing primarily with Java, but also with other languages, in particular PHP, C/C++, and HTML5.
• Qt Creator ⚡ - A cross-platform C++, JavaScript and QML IDE which is part of the SDK for Qt.
• rtags - A c/c++ client/server indexer with for integration with emacs based on clang.
• Xcode - Developed by Apple.
• YouCompleteMe - YouCompleteMe is a fast, as-you-type, fuzzy-search code completion engine for Vim.
• cquery - A C++ code completion engine for vscode, emacs, vim, etc.

Build Systems

• Bazel - A multi-language, fast and scalable build system from Google. [Apache]
• Bear - A tool to generate compilation database for clang tooling. [GPLv3]
• Buck - A fast build system that encourages the creation of small, reusable modules over a variety of platforms and languages including C++ developed and used at Facebook. Written in Java. [Apache]
• build2 - cross-platform build, packaging and dependency management toolchain for developing and packaging C/C++ projects. [MIT]
• clib - Package manager for the C programming language. [MIT]
• CMake - Cross-platform free and open-source software for managing the build process of software using a compiler-independent method. [BSD]
• Cget - Cmake package retrieval. [Boost] website
• Conan - C/C++ Package Manager, open sourced. [MIT]
• CPM - A C++ Package Manager based on CMake and Git.
• FASTBuild - High performance, open-source build system supporting highly scalable compilation, caching and network distribution.
• Hunter - CMake driven cross-platform package manager for C++. [BSD-2]
• MesonBuild - An open source build system meant to be both extremely fast, and, even more importantly, as user friendly as possible.
• Ninja - A small build system with a focus on speed.
• Scons - A software construction tool configured with a Python script.
• Sconsolidator - Scons build system integration for Eclipse CDT.
• Spack - A flexible package manager that supports multiple versions, configurations, platforms, and compilers. [Apache-2.0/MIT]
• SW - Cross-platform C++ (and other langs) Build System and Package Manager with a lot of packages available. [GPLv3]
• tundra - High-performance code build system designed to give the best possible incremental build times even for very large software projects.
• tup - File-based build system that monitors in the background for changed files.
• Premake - A tool configured with a Lua script to generate project files for Visual Studio, GNU Make, Xcode, Code::Blocks, and more across Windows, Mac OS X, and Linux.
• Vcpkg - C++ library manager for Windows, Linux, and MacOS. [MIT]
• waf - Python-based framework for configuring, compiling and installing applications. [BSD] website
• XMake - A C/C++ cross-platform build utility based on Lua. [Apache]

Static Code Analysis

List of tools for improving quality and reducing defects by code analysis

• Cppcheck - A tool for static C/C++ code analysis. - source
• CppDepend - Simplifies managing a complex C/C++ code base by analyzing and visualizing code dependencies, by defining design rules, by doing impact analysis, and comparing different versions of the code.
• cpplint - A C++ style checker following Google's C++ style guide.
• PVS-Studio - A tool for bug detection in the source code of programs, written in C, C++ and C#.
• cpp-dependencies - Tool to check C++ #include dependencies (dependency graphs created in .dot format). [Apache]
• include-what-you-use - A tool for use with clang to analyze includes in C and C++ source files. website
• Infer - A static analyzer for Java, C and Objective-C. [BSD]
• OCLint - A static source code analysis tool to improve quality and reduce defects for C, C++ and Objective-C. - source
• Clang Static Analyzer - A source code analysis tool that finds bugs in C, C++, and Objective-C programs.
• Linticator - Eclipse CDT integration of Pc-/FlexeLint.
• IKOS - Static analyzer for C/C++ based on the theory of Abstract Interpretation. [NOSA 1.3]
• List of tools for static code analysis - A list of tools for static code analysis from Wikipedia.
• OptView2 - Inspect missed Clang optimizations
• Trunk - Toolkit to check, test, merge, and monitor code.

Coding Style Tools

• Artistic Style - A tool to format C/C++/C#/Obj-C/Java code. Also known as astyle.
• ClangFormat - A tool to format C/C++/Obj-C code.
• Clang-Tidy - Clang-based C++ linter tool.
• EditorConfig - EditorConfig helps maintain consistent coding styles across different editors and IDEs.
• Uncrustify - Code beautifier.

Resources

Various resources, such as books, websites, and articles for improving your C++ development skills and knowledge.

API Design

• Beautiful Native Libraries
• Designing Qt-Style C++ APIs

Articles

Fantastic C++ related articles.

• CppCon 2020 Presentation Materials - CppCon 2020 Presentation Materials.
• CppCon 2019 Presentation Materials - CppCon 2019 Presentation Materials.
• CppCon 2018 Presentation Materials - CppCon 2018 Presentation Materials.
• CppCon 2017 Presentation Materials - CppCon 2017 Presentation Materials.
• CppCon 2016 Presentation Materials - CppCon 2016 Presentation Materials.
• CppCon 2015 Presentation Materials - CppCon 2015 Presentation Materials.
• CppCon 2014 Presentation Materials - CppCon 2014 Presentation Materials.
• C++Now 2019 Presentations - Presentation materials presented at C++Now 2019.
• C++Now 2018 Presentations - Presentation materials presented at C++Now 2018.
• C++Now 2017 Presentations - Presentation materials presented at C++Now 2017.
• C++Now 2016 Presentations - Presentation materials presented at C++Now 2016.
• C++Now 2015 Presentations - Presentation materials presented at C++Now 2015.
• C++Now 2014 Presentations - Presentation materials presented at C++Now 2014.
• C++Now 2013 Presentations - Presentation materials presented at C++Now 2013.
• C++Now 2012 Presentations - Presentation materials presented at C++Now 2012.

Books

Fantastic C or C++ related books.

• List of Free C or C++ Books
• Free C Books - vhf/free-programming-books/C.
• Free C++ Books - vhf/free-programming-books/C++.
• cppbestpractices - Collaborative Collection of C++ Best Practices.

Coding Standards

• Cert C++
• Misra C++ 2008
• Autosar C++ 2014

Coding Style

• C++ Core Guidelines - "Official" set of C++ guidelines, reviewed by the author of C++.
• C++ Dos and Don'ts - The Chromium Projects > For Developers > Coding Style > C++ Dos and Don'ts.
• google-styleguide - Style guides for Google-originated open-source projects.
• Google C++ Style Guide
• GNU Coding Standard
• Linux kernel coding style
• LLVM Coding Standards

Podcasts

• CppCast - The first podcast by C++ developers for C++ developers.
• CppChat - A (sometimes) weekly look at what's going on in the world of C++ chatting with a guest from the community.

Talks

• CppCon Talks ⚡ - The C++ conference.
• Quick game development with C++11/C++14 - CppCon 2014 talk by Vittorio Romeo.
• Presentation on Hana for C++Now 2015
• Meeting Cpp - Meeting C++ Youtube Channel

Videos

Fantastic C or C++ related videos.

• List of C or C++ YouTube Videos
• Awesome C Programming Tutorials in Hi Def [HD] - A collection of detailed C Programming Language Tutorials for Beginners and New Programmers.
• C++ - by VoidRealms.
• C++ Qt Programming - by VoidRealms.
• C++ Programming Tutorials Playlist - TheNewBoston Official Buckys C++ Programming Tutorials Playlist.
• C++ Programming Tutorials from thenewboston - These are all of thenewboston's C++ programming tutorials.
• C++ GUI with Qt Playlist - Official Playlist for thenewboston C++ GUI with Qt tutorials.
• C Programming Tutorials - All of TheNewBoston's C programming tutorials are right here.
• Bo Qian's playlist - Boost Library, C++ Standard Library, Modern C++, Advanced C++, Advanced STL, ...

Websites

Useful C or C++ related websites.

• Standard C++ ⚡ - News, Status & Discussion about Standard C++.
• CppCon - The C++ Conference.
• C++ reference - C++98, C++03, C++11, C++14 reference.
• C++ by Example - Learn C++ by Example.
• cplusplus.com - The C++ Resources Network.
• C FAQ - C frequently asked questions.
• C++ FAQ - C++ frequently asked questions.
• C++ FQA Lite - C++ frequently questioned answers.
• Guru of the Week - A regular series of C++ programming problems created and written by Herb Sutter.
• Meeting C++
• C++ Quiz - C++ quiz in which you propose to find errors in code fragments of open source projects.
• Udemy C++ Courses and Tutorials
• C++ Hints - Every business day hints about most often C++ mistakes and ways to solve them from PVS-Studio Team.
• C++ tutorial - A user ranked online tutorial bank site displaying multiple courses to learn C++ from.
• C++ Tutorial for Beginners - A comprenhensive tutorial on C++ curated by trained experts.

Weblogs

Useful C or C++ related weblogs.

• Coding For Speed - Coding For Speed DOT COM, Less Execution Time.
• Eric Niebler
• Sticky Bits
• Paul Fultz II's Blog
• ridiculousfish - Will It Optimize?
• Embedded in Academia
• Simplify C++
• Fluent C++
• Bartek's Coding Blog
• Kenny Kerr
• Sutter’s Mill
• Vorbrodt's C++ Blog
• foonathan::blog()

Other Awesome Projects

Collection of useful codes, snippets, ...

• algorithms - Algorithms & Data Structures in C++.
• c-algorithms - C algorithms library.
• C++ Awesome Pack - Contains some awesome c++ codes, packed in one.
• 30 Seconds of C++

Other Awesome Lists

Other amazingly awesome lists

• lists - List of (awesome) lists curated on GitHub.
• awesome-awesomeness - A curated list of awesome awesomeness.
• awesome ⚡ - A curated list of awesome lists.
• C++ links - A categorized list of C++ resources.
• Awesome C++ - getAwesomeness()'s mirror.
• Awesome C++ - LibHunt's mirror.
• Awesome C 1
• Awesome C 2
• Awesome Modern C++ - A collection of resources on modern C++.
• AwesomePerfCpp - A curated list of awesome C/C++ performance optimization resources.
• free-programming-books - List of Freely Available Programming Books.
• Inqlude - The Qt library archive.
• papers-we-love - Papers from the computer science community to read and discuss.
• awesome-algorithms - A curated list of awesome places to learn and/or practice algorithms.
• awesome-talks - A lot of screencasts, recordings of user group gatherings and conference talks.
• Projects - A list of practical projects that anyone can solve in any programming language.
• Awesome interview questions - A list of lists of interview questions for the most popular technologies, including C and C++.
• nothings/single_file_libs ⚡ - List of single-file C/C++ libraries.

Contributing

Please take a quick gander at the contribution guidelines for details. Thanks to all contributors; you rock!

If you see a project or link here that is no longer maintained or is not a good fit, please submit a pull request to improve this document. Thank you!