Metaspec C# parser library is designed to provide the kernel for applications which require processing C# source code: refactoring, formatting, and verification applications, and other similar tools. C# parser is fully compliant with ECMA-334 and ECMA-335 standards. In addition, it supports Microsoft-specific extensions. C# parser is available in two versions: a compilation parser and a transformation parser. The compilation parser is designed for applications that require converting source code into the internal format as fast as possible. Only the significant data required for correct analysis of the program is preserved. This parser is useful for the development of compilers, interpreters, analyzers and other tools that do not require modification of source code. The transformation parser preserves all information in the program's source code (including comments, spaces and preprocessing directives). This parser is useful for the development of refactoring and formatting utilities and other programs that do transformations on the program's source code.