1. An apparatus for generating, validating and applying custom extensible markup language (XML) configuration on a specific-purpose local client having a windows-based embedded image and obviating reinstallation of an entire windows-based embedded image onto the specific-purpose local client, the apparatus comprising: a processor; a memory communicatively coupled to the processor; and processing instructions encoded in the memory, the processing instructions, when executed by the processor, operable to perform operations comprising: generating an XML configuration file; validating the XML configuration file based on a validation file; and saving the XML configuration file to storage location accessible by the specific-purpose local client each time the specific-purpose local client boots up, the XML configuration file operable to, when executed by a processor of the specific-purpose local client, automatically apply a configuration change to the windows-based embedded image; wherein the configuration change persists across a reboot of the specific-purpose local client while obviating reinstallation of an entire windows-based embedded image with the configuration change on the specific-purpose local client; and wherein the windows-based embedded image supports a graphical user interface and comprises an operating system and one or more applications dedicated to the specific purpose.