Do you know a way to test that the long loop is the issue? or is this an educated guess based on your knowledge of the JIT?

Wow, never seen that bug before. I've created a issue ticket ( https://github.com/bramp/js-sequence-diagrams/issues/39 ), and I will fix it shortly.

Fixed. Turns out to be a bug in Raphaël (the graphic library).

Yup! and suitable attribution is given.

I just spent a lot of time looking at the various examples on zaach.github.com. I actually started to write a blog article on it but never finished. Maybe I'll finish it.

and from my understanding it was meant to be a drop in replacement for underscore.js, but I had to change at least one thing to make it work. https://github.com/bramp/js-sequence-diagrams/commit/2677cdf...

I submitted an issue to lodash, feel free to add to it: https://github.com/bestiejs/lodash/issues/215

Async is supported today by using ->>, to have a open arrow head. I plan to add multiple other diagramming elements.

That's the next feature I plan to add