system-designer
system-designer is a low‑code platform for designing complete systems using a visual model derived from UML and stored in the MSON JSON format. The model defines types, classes, relationships and inheritance, and the tool generates skeleton classes and component structures that developers can augment with behavior code. Components are managed like NoSQL documents, and the platform provides instant dynamic type checking and debugging while the system runs in a browser or Node.js. It works on Windows, macOS, Linux, iOS, iPad, Android and any modern browser, supports synchronization across devices, and can export the model or generated code as HTML, JSON, JavaScript, a Node module or a Graphviz diagram.