System Designer: A low-code development platform for creating systems (Free program)

System Designer is a free open source app that helps you to design systems and system components and generate the right classes for your workflow requirement.


With System Designer you create in fact a system and not an application. But what is a system ?

A system:

  • is defined by a model,
  • is composed by components and
  • reacts to events with actions that we call behaviors.

How does it work?

System Designer uses UML, a standard, to define your model. So you probably already know how to design in System Designer even if you have never run it.

The definition of the model is stored on a JSON format called MSON. With MSON you can define types, classes, one to one / one-to-many relationships and multi inheritance between classes.

Once you have created your model, System Designer generates the skeletons of all your methods. You only have then to add your code to implement them.

System Designer provides you helpers to manage your components. You can easily navigate through components to create your application.

There is no need to code to instantiate a component. Create a component in System Designer is like creating a document in a NoSQL Database.

In fact, System Designer acts as an ODM (Object-Document Mapper) to manage your components as NoSQL Documents.

You can run your system directly from System Designer and then export it to HTML, JSON, JavaScript, a Node.js module or a Graphviz file (* macOS, Windows, Linux, and PWA version only).

Because you have defined a model for your application, a Dynamic Type Check is done on every action of your system. All warnings are sent and shown in System Designer.


Copyright © 2022 Erwan Carriou

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License here.


macOS Windows and Linux


Apache-2.0 License


UML,design,development,devtools,web development,programming,JSON,HTML,graphics,system,MSON,productivity,tools



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