rgexf bitbucket.org

Oracle Solaris Studio oracle.com

C, C++ and Fortran compiler for SPARC and x86. Supports C++11. Available on Linux and Solaris. [OTN Developer License]

OpenVDB openvdb.org

Library and tools for storing, editing, and rendering volumetric datasets. [MPL2]

fastR bitbucket.org

OpenSceneGraph openscenegraph.org

An open source high performance 3D graphics toolkit. [OSGPL]

Bioconductor bioconductor.org

OpenEXR openexr.com

Cross-platform library for high dynamic range imaging. [Modified BSDF]

Bio7 bio7.org

OpenAL openal.org

Open Audio Library - A crossplatform audio API. [BSD/LGPL/Proprietary]

arrow arrow.apache.org

Conda anaconda.org

All C++20 core language features with examples oleksandrkvl.github.io

A reference of all C++20 core language features with examples.

Ninja ninja-build.org

A small build system with a focus on speed.

Advanced R, 2nd ed. by Hadley Wickham (2019) adv-r.hadley.nz

MRPT mrpt.org

Mobile Robot Programming Toolkit. [BSD]

MOOS-IvP moos-ivp.org

A set of open source C++ modules for providing autonomy on robotic platforms, in particular autonomous marine vehicles.

libsequence molpopgen.github.io

A C++ library for representing and analyzing population genetics data. [GPL]

MiniScript miniscript.org

scripting language modern, elegant, easy to learn, and easy to embed in your own C# or C++ projects. [MIT]

Metashell metashell.readthedocs.org

An interactive template metaprogramming shell which includes the MDB metadebugger.

MesonBuild mesonbuild.com

An open source build system meant to be both extremely fast, and, even more importantly, as user friendly as possible.

Meeting C++ meetingcpp.com

Choosing Some C++ Over C medium.com

An article about when to use C++ instead of C.

Lithium matt-42.github.io

Build high performance C++ HTTP servers without being a C++ expert. [MIT]

Beautiful Native Libraries lucumr.pocoo.org

Lua lua.org

A minimal and fast scripting engine for configuration files and basic application scripting. [MIT]

Loki loki-lib.sourceforge.net

A C++ library of designs, containing flexible implementations of common design patterns and idioms. [MIT]

Log4cpp log4cpp.sourceforge.net

A library of C++ classes for flexible logging to files, syslog, IDSA and other destinations. [LGPL]

LLVM Coding Standards llvm.org

LLDB lldb.llvm.org

The LLDB Debugger.

LIVE555 Streaming Media live555.com

Multimedia streaming library using open standard protocols (RTP/RTCP, RTSP, SIP). [LGPL]

litePDF litepdf.sourceforge.io

Library to create and edit PDF documents that uses GDI functions through a device context to draw the page content. [LGPL v3 and zlib]

Linticator linticator.com

Eclipse CDT integration of Pc-/FlexeLint.

libxml++ libxmlplusplus.sourceforge.net

An XML Parser for C++. [LGPL2]

libusb libusb.info

A universal USB library which allows for portable access to USB devices. [LGPL2]

LibreSSL libressl.org

A free version of the SSL/TLS protocol forked from OpenSSL in 2014. [?]

Expat libexpat.org

An XML parser library written in C. [MIT]

libevent libevent.org

An event notification library. [BSD]

libev libev.schmorp.de

A full-featured and high-performance event loop that is loosely modelled after libevent, but without its limitations and bugs. [BSD and GPL]

LAME lame.sourceforge.io

LAME is a high quality MPEG Audio Layer III (MP3) encoder. [LGPL]

Kore kore.io

ultra fast and flexible web server / framework for web applications developed in C. [ISC]

VLD kinddragon.github.io

Visual Leak Detector. A free, robust, open-source memory leak detection system for Visual C++.

Linux kernel coding style kernel.org

Kenny Kerr kennykerr.ca

ITK itk.org

An open-source, cross-platform system for image analysis. [Apache2 from ITK 4.0]

Standard C++ isocpp.org

zap: - News, Status & Discussion about Standard C++.

Ncurses invisible-island.net

A terminal user interface. [MIT]

InterviewBit interviewbit.com

A simple and easy to use online C++ compiler.

MagickWnd imagemagick.org

ImageMagick program interfaces for C. [Apache2]

Magick++ imagemagick.org

ImageMagick program interfaces for C++. [Apache2]

Ideone ideone.com

An online compiler and debugging tool which allows you to compile source code and execute it online in more than 60 programming languages.