Matreshka is an Ada framework to develop information systems:

 League - a set of reusable components aimed at providing high level
 abstractions for  internationalization of applications, as well as a portable
 interface to different operating systems. Other features, include advanced
 calendrical calculations, regular expressions, and JSON support for processing
 and generation.

 XML processor - manipulating of streams and documents; including SAX reader,
 and writer; XML1.0, XML1.1, Namespaces support and XML Base specifications;
 DOM API to process XML documents 0.8; XML Catalogs resolver; Markup Templates
 Engine to process XML templates and generates XML or HTML/XHTML output 0.6.

 Web framework SpikeDog - implemented over AWS (Ada Web Server) with Servlet
 API 0.7. FastCGI. SOAP 1.2 supported, including WS-Security module 1.1.

 SQL database access - provides a generic API for accessing SQL databases:
 Firebird, MySQL, Oracle, PostgreSQL, SQLite3.

 Ada Modeling Framework - an implementation of OMG's Meta Object
 Facility (MOF) written completely in Ada. Extension modules are provided to
 assist in the analysis and modification of, UML models and their
 extensions. MOF Extensions to support metamodeling OCL models UML Testing
 Profile to support Model-Driven Testing Diagram Definition