Fig3. Kwalify validates a YAML document.

Kwalify is a parser, schema validator, and data binding tool for YAML and JSON.

YAML and JSON are simple and nice format for structured data and easier for human to read and write than XML. But there have been no schema for YAML such as RelaxNG or DTD. Kwalify gets over this situation.

From version 0.7, Kwalify supports data binding. If you specify class name in schema file, Kwalify YAML parser creates instance objects of that class instead of Hash objects. It means that you don't have to convert Hash into proper object any more. Data binding makes YAML much easier to handle and manipurate

See Users' Guide for details.


  • for Ruby
    • If you have installed RubyGems, just type 'gem install kwalify' to install Kwalify.
    • Or download from
  • for Java



  • MIT License