C++Builder is a rapid application development (RAD) environment, developed by Borland and as of 2009 owned by Embarcadero Technologies, for writing programs in the C++ programming language. C++Builder combines the Visual Component Library and IDE written in Delphi with a C++ compiler. Traditionally, the release cycle was such that Delphi got major enhancements first, with C++Builder following, though recent versions have been released at the same time as their Delphi equivalents. Most components developed in Delphi can be used in C++Builder with no modification, although the reverse is not true.
C++Builder includes tools that allow true drag-and-drop visual development, making programming easier by incorporating a WYSIWYG GUI builder into its IDE.
C++Builder uses the same IDE as Delphi, and shares many core libraries. Notable shared Delphi (Pascal code) and C++ Builder routines include the FastMM4 memory manager, which was developed as a community effort within the FastCode project, the entire UI framework known as the VCL, which is written in Pascal, as well as base system routines, many of which have been optimised for both Delphi and C++Builder through the FastCode project.
C++Builder projects can include Delphi code. The Delphi compiler emits C++ headers, allowing C++ code to link to Delphi classes and methods as though they were written in C++. The reverse (C++ code being used by Delphi) is not possible.
C++Builder originally targeted only the Microsoft Windows platform. Later versions incorporated Borland CLX, a cross-platform development visual component library based on Qt, that supports Windows and Linux, however CLX is now abandoned. A cross-platform version for Linux and OSX is reportedly planned.