ClevaDesk is a flexible IT-system with a set of business applications. It includes ECM system with the set of business applications, visual designer to create web apps of different complexity and web interfaces to IBM Lotus Notes/Domino apps. Only a web browser is required to change and develop capabilities of the system. Specialist training takes only a few hours. Web Designer can build different IT-systems without programming. Architecture of ClevaDesk is focused on working with large data. It uses the relational and nonrelational database at the same time. It is a complete solution with enhanced security level enabling high speed design and easy maintenance.