Love this. I think we are missing a UI paradigm for visualizing and editing graphs effectively, and I love seeing stabs at the problem. It is absolutely insane that dependency graphs aren't a first-class feature in all issue trackers. The fact that graph visualizers are so complex is probably a big part of it. I'm a fan of your approach because it's reusing familiar UX patterns that people already know, like making nested lists.

If you haven't already, you should check out Workflowy! You would be a fan of their design, since everything is centered around recursive lists and operations on them. They also noticed that lists are isomorphic to boards, so any list can be shown (and edited!) as a board without loss of information. I could imagine a similar isomorphism from those lists to graphs, which knotend visualizes.

I had trouble using the tool though, here's some things I noticed:

* <Tab> doesn't work when the graph is empty, and causes the "Sign in" link to get selected instead.

* It feels like nodes can be in different states depending on if I'm editing the text, or just have it selected. For example, typing a name and hitting <Tab> does not create the child. Looks like the app is trying to mimic spreadsheets, so this is surprising. Same with <Enter>, I'd expect it to make a sibling whether I'm in editing mode or not.

* The curved connecting lines between nodes don't scale well, and look a bit strange. This is a big problem, because knotend has to work just as well with small or huge graphs. Given a node, I have to know which nodes are up- and downstream of it immediately. As is, it gets confusing the moment I have two sibling nodes each with disjoint/shared children. ObservableHQ handles this by highlighting connectors to the parent and child nodes.

Definitely looking forward to seeing how this grows! I think it's close, but for it to be as easy as writing lists, there can't be a distinction between editing and not-editing.