The language is very, very nice.<p>However, if I ran into this incidentally (not posted to HN for review), I would never use this. I'd see the lack of a github link on the top right, and assume it's a some kind of startup making some prototype hosted tool.<p>The only way to find out this is open-source is to click "about," read to the third paragraph, see github mentioned, click through the link, and click on the license.<p>My major piece of feedback is to add a github link to the icons at the top-right of the page. A .org might also be nicer than a .com.<p>To people asking why this and not a graphical tool?<p>To me, the overhead to moving a graphical tool is very large:<p>1) I like being able to manage files on github and be able to use common tooling.<p>2) If someone (including myself, two years later) needs to install Vizio, Illustrator, or whatever other tool to edit my diagrams, pay for a cloud service, or worse, recover something which was hosted in a discontinued tool, I'm SOL.<p>3) Discovery is big too. I can use normal search tools to find things. If something is locked away in a .ai file, a .docx file, or a cloud service, and I lose it, it's likely lost forever.<p>95% of the cost of most projects is maintenance, and even if I invest 10x the time up-front into making a diagram in a tool like this (e.g. an hour to learn it, tweak it, and get the diagram I want, instead of 5 minutes in my favourite GUI), that will pay much than an hour in dividends down the line. I use Markdown, LaTeX, and similar for large or important documents because, in the long term, they save time.