When I used Scratch with my daughter, I noticed how intuitive is thinking in blocks (and nested blocks), and I wondered why we were not building charts similarly with javascript. It was fun and it helped to ideate through one of the most natural process: addition.

I thought that creating charts could be as simple as plugging blocks one after the other (or inside each other):

  • add a chart canvas block
  • add a line chart block
  • add an axis block
  • …and so on…

Yep! A system like this could be easily translated into Scratch blocks, or in more traditional programming languages:


The layered grammar of graphics at the foundation of ggplot2 is based on a similar model. And I love it! However, ggplot2 is for R, it has a steep learning curve and can be tricky to visually customize.

The system I was thinking about had to be simple, intuitive and with default settings to build beautifully crafted charts. Yes, beautifully crafted. I’ve experimented with many chart libraries and I still have to find one that is easy to customize and that enforces the best practices (yes, I’m talking to you, rotated axis titles!).

The goal was outlined: a block-based javascript library to create beautiful charts in a fun way.

And that’s how chrt started