CppUnit freedesktop.org

C++ port of JUnit. [LGPL2]

foonathan::blog() foonathan.net

FMOD fmod.org

An easy to use crossplatform audio engine and audio content creation tool for games. [Free for non-commercial/Commercial]

Fluent C++ fluentcpp.com

FLTK fltk.org

Fast, light, cross-platform C++ GUI toolkit. [LGPL2]

Fil-C fil-c.org

a fanatically compatible memory-safe implementation of C and C++.

FastFormat fastformat.org

Fast, Safe C++ Formatting inspired by log4j and Pantheios. [Simplified BSD]

FASTBuild fastbuild.org

High performance, open-source build system supporting highly scalable compilation, caching and network distribution.

Eric Niebler ericniebler.com

Evolving Objects eodev.sourceforge.net

A template-based, ANSI-C++ evolutionary computation library which helps you to write your own stochastic optimization algorithms insanely fast. [LGPL]

Standard Template Library en.wikipedia.org

The Standard Template Library (STL).

Comparison of debuggers en.wikipedia.org

A list of Debuggers from Wikipedia.

C POSIX library en.wikipedia.org

A specification of a C standard library for POSIX systems.

C++ Standard Library en.wikipedia.org

A collection of classes and functions, which are written in the core language and part of the C++ ISO Standard itself.

Eigen eigen.tuxfamily.org

A high-level C++ library of template headers for linear algebra, matrix and vector operations, numerical solvers and related algorithms. [MPL2]

EditorConfig editorconfig.org

EditorConfig helps maintain consistent coding styles across different editors and IDEs.

Eclipse CDT eclipse.org

A fully functional C and C++ IDE based on the Eclipse platform.

DynaPDF dynaforms.com

An easy-to-use PDF generation library. [Commercial]

ACE dre.vanderbilt.edu

An OO Network Programming Toolkit in C++. [?MIT?]

Microsoft Visual C++ docs.microsoft.com

MSVC, developed by Microsoft.

Designing Qt-Style C++ APIs doc.qt.io

djinni djinni.xlcpp.dev

A tool for generating cross-language type declarations and interface bindings. [Apache2]

DCMTK dicom.offis.de

DICOM Toolkit.

Thrust developer.nvidia.com

A parallel algorithms library which resembles the C++ Standard Template Library (STL). [Apache2]

C++ Team Blog devblogs.microsoft.com

Dev blog from the Microsoft Visual C++ team

CUTE cute-test.com

C++ Unit Testing Easier. [LGPL3]

libcurl curl.haxx.se

Multiprotocol file transfer library. [MIT/X derivate license]

Chaste cs.ox.ac.uk

An open source C++ library for the computational simulation of mathematical models developed for physiology and biology. [BSD]

cppstat cppstat.dev

A site that lists C++ features and their support by compilers and standard library implementations in an accessible way.

C++ reference cppreference.com

A complete online reference for the C and C++ languages and standard libraries.

C++ Quiz cppquiz.org

A simple online quiz that you can use to test your knowledge of the C++ programming language.

C++ Hints cpphints.com

Every business day hints about most often C++ mistakes and ways to solve them from PVS-Studio Team.

Misra C++ 2008 cppdepend.com

CppCon cppcon.org

The C++ Conference.

CppCMS cppcms.com

A Free High Performance Web Development Framework (not a CMS). [LGPLv3]

Cppcheck cppcheck.sourceforge.net

A tool for static C/C++ code analysis. - source

CppCast cppcast.com

The first podcast by C++ developers for C++ developers.

Awesome C++ cpp.libhunt.com

LibHunt's mirror.

CppChat cpp.chat

A (sometimes) weekly look at what's going on in the world of C++ chatting with a guest from the community.

cpp-netlib cpp-netlib.org

A collection of open-source libraries for high level network programming. [Boost]

cplusplus.com cplusplus.com

The C++ Resources Network.

libOnion coralbits.com

lightweight library to help you create webservers in C programming language. [LGPLv3]

Conan conan.io

C/C++ Package Manager, open sourced. [MIT]

CompileBytes C++ Compiler compilebytes.com

Online C++ compiler and interactive code execution environment.

coliru coliru.stacked-crooked.com

Online compiler/shell with support for various C++ compilers.

Coding For Speed codingforspeed.com

Coding For Speed DOT COM, Less Execution Time.

ODB codesynthesis.com

An open-source, cross-platform, and cross-database object-relational mapping (ORM) system for C++. [GPLv2]

CxImage codeproject.com

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]

CodeLite codelite.org

Another cross-platform, free C and C++ IDE. [GPL2 with an exception for plugins]

codechef codechef.com

A simple online compiler CodeChef.