[dublin]

TiddlyWiki has hit most of these capabilities for many years now, and is nearly unique in wrapping up all the code and data in a single unit that can be run in any regular browser, from either local storage or a remote server or storage. (It does need a killer web clipper, though...)

TiddlyWiki really is one of the cleverest apps I've ever run across, but I'm not much of a JS programmer, so it's got a bit of a learning curve if you want to hack on it. It's pretty easy to use right out of the box if you don't want to hack on it, though, and I'm giving some thought to moving most of the data I've collected in OneNote to TiddlyWiki to escape Microsoft's clutches after I've finally disentangled myself from Google... One thing I love is that TiddlyWikis I built 20 years ago (granted, they were simpler then) are still perfectly usable today.

My perfect data keeper might be something of a mashup between TiddlyWiki and a JuPyteR notebook.

[bachmeier]

Another nice thing about TiddlyWiki is that you don't actually have to be a JS programmer to extend it.

I run a local CGI server and that allows me to make all kinds of customizations in the language I want (most languages support local CGI servers). The querying capabilities of TiddlyWiki make it a nice database.