# Crystal Programming Language Copyright 2012-2024 Manas Technology Solutions. This product includes software developed at Manas Technology Solutions (<https://manas.tech/>). Apache License v2.0 applies to all works. Please see [LICENSE](/LICENSE) for additional copyright and licensing information. ## External libraries information Crystal compiler links the following libraries, which have their own license: * [LLVM][] - [Apache-2.0 with LLVM exceptions][] * [PCRE or PCRE2][] - [BSD-3][] * [libevent2][] - [BSD-3][] * [libiconv][] - [LGPLv3][] * [bdwgc][] - [MIT][] Crystal compiler calls the following tools as external process on compiling, which have their own license: * [pkg-config](https://www.freedesktop.org/wiki/Software/pkg-config/) - [GPLv3] Crystal standard library uses the following libraries, which have their own licenses: * [LLVM][] - [Apache-2.0 with LLVM exceptions][] * [PCRE or PCRE2][] - [BSD-3][] * [libevent2][] - [BSD-3][] * [libiconv][] - [LGPLv3][] * [bdwgc][] - [MIT][] * [Zlib][] - [Zlib][Zlib-license] * [OpenSSL][] - [Apache-2.0][] * [Libxml2][] - [MIT][] * [LibYAML][] - [MIT][] * [readline][] - [GPLv3][] * [GMP][] - [LGPLv3][] Crystal playground includes the following libraries, which have their own licenses. (There are these files under [/src/compiler/crystal/tools/playground/public/vendor](/src/compiler/crystal/tools/playground/public/vendor)): * [jQuery][] - [MIT][] `Copyright JS Foundation and other contributors, https://js.foundation/` * [Octicons][] - [MIT][] `(c) 2023 GitHub Inc.` * [Materialize][] - [MIT][] `Copyright (c) 2014-2015 Materialize` * [CodeMirror][] - [MIT][] `Copyright (C) 2016 by Marijn Haverbeke <marijnh@gmail.com> and others` * [ansi\_up][] - [MIT][] `Copyright (c) 2011 Dru Nelson` <!-- licenses --> [Apache-2.0]: https://www.openssl.org/source/apache-license-2.0.txt [Apache-2.0 with LLVM exceptions]: https://raw.githubusercontent.com/llvm/llvm-project/main/llvm/LICENSE.TXT [BSD-3]: https://opensource.org/licenses/BSD-3-Clause [GPLv3]: https://www.gnu.org/licenses/gpl-3.0.en.html [LGPLv3]: https://www.gnu.org/licenses/lgpl-3.0.en.html [MIT]: https://opensource.org/licenses/MIT [OFL-1.1]: https://opensource.org/licenses/OFL-1.1 [Zlib-license]: https://opensource.org/licenses/Zlib <!-- libraries --> [ansi\_up]: https://github.com/drudru/ansi\_up [bdwgc]: http://www.hboehm.info/gc/ [CodeMirror]: https://codemirror.net/ [jQuery]: https://jquery.com/ [GMP]: https://gmplib.org/ [libevent2]: http://libevent.org/ [libiconv]: https://www.gnu.org/software/libiconv/ [Libxml2]: http://xmlsoft.org/ [LibYAML]: http://pyyaml.org/wiki/LibYAML [LLVM]: http://llvm.org/ [Materialize]: http://materializecss.com/ [Octicons]: https://octicons.github.com/ [OpenSSL]: https://www.openssl.org/ [PCRE or PCRE2]: http://pcre.org/ [readline]: https://tiswww.case.edu/php/chet/readline/rltop.html [Zlib]: http://www.zlib.net/