Configurator is a configuration file parser. It allows you to use arbitrary nesting of sections. The user can define an option's default value, necessity, and semantic check. It supports single-line and multi-line comments (in C++ style). It provides common checks of options and sections, like duplication, incorrection, etc. It uses only Boost C++ libraries and ISO C++. It is header-only (does not require building) and very easy to use.