Libraries and dev tools to visualise your software's architecture, data flow, and business logic to make it easier to Develop, Test, Debug, Monitor ...

How does it work?

1. Use collar libraries to create your code.

You can use the simple collar reactive library to build your software from scratch

Or you can use our high-level frameworks to build your software with the traditional OOP or API style

You can even wrap your current code with our library to benefit from all the features

// reactive style coding 
const ns = 

ns.when('increment action')
  .do('get the state')
  .map('increase state by 1')
  .do('set the state')
// framework style coding
const app = 
  .reduce('INCREMENT', (prevState, action) => {
    return prevState + 1;

2. enable collar addons.

Use different addons to collect the information

  .use(new DevToolAddon())
  .use(new TestAddon())

3. develop & operate your software with collar dev tool.

We provide several development & operation tools to help you solve different problems in software development & operation life cycle.


Reactive Programming

CollarTechs keeps Reactive Manifesto in mind to design the libraries and dev tools. By using the provided reactive programming library, you can easily build your software in a functional programming way.

Live coding everything

Live coding is no longer a feature only designed for front-end. With collar techs, both of your front-end and back-end application can benefit live coding. You can visualise your software's architecture and data flow in real time.

Record & Playback

You can record your data flow in collar dev tool, and play it back to understand your software's dynamic data flow, and see how data propagates and evolves in your software.

Live Testing

You can test your software during the development from the very beginning, without a single line of test code.

Deep Testing

Your tests are no longer limited to the unit test for functions, class and modules. You can easily make cross class, cross module, or event cross process test


Reactive Library

You can use the reactive javascript library collar.js to build your front-end and back-end (node.js) javascript application:

npm install --save collar.js

Alternatively, you can directly download the minified version from the following github repository: for your web application

Addons for collar.js



Predefined Frameworks for javascript

We have built the following frameworks with collar.js to bootstrap your development too:

- Redux/Flux framework: Collux

More frameworks coming soon ...

Development & Operation tools

Install collar-dev-server on your machine through npm:

sudo npm install collar-dev-server -g

Next, run collar-dev-server


Open collar dev tool from browser


Run your application with collar dev client addon enabled, you will see your application's architecture and data flow in dev tool. More detail see the document of collar-dev-server

More development & operation tools coming soon ...

Contact Us

Feel free to email us to provide some feedback on our libraries and tools, give us suggestions for new features, or to just say hello!