I know the NoSQL world had some progress in this space. RethinkDB was going in this direction around a decade ago if I recall. I would really like this from a modern relational database or data warehouse though. Polling sucks.
Schema-less is a bit wrong term, since you always end up with one but, indeed, schema-on-read vs schema-on-write discussion for individual use cases is far from a settled thing, even though the zeitgeist is that schema-on-write won sometime in the 70s.
You say "prototyping", but I would generalize that to "faster evolving" in the long term. Of course, not without tradeoffs.
I personally have zero issues writing a custom marshaller when needed for any the schema-less document collections I have. Constraints your application has on the data are a superset of db schema anyways.
Just to add to sibling comments, one killer feature for me is ChangeStreams[1]. It's miles ahead of what Postgres[2] offers, and it enables really interesting use cases. Some of my services built around ChangeStreams end up not doing a single query to the DB. Data is right there in the program memory, indexed how I need it to be, and program is immediately reactive to any changes in the DB.
OpenResty with Redis on the same system - both Lua-powered - is a god-like power.
Ability to do basically control and rewrite all your ingress AND egress and have some state via Redis over UNIX sockets.
What's not to love? After all, it's what powers the bulk of internet.
Granted, it sounds dreamier than it is, since a lot of the contraptions you could come up with might be better placed at application layer. But having operational ability to do these things ad-hoc, security advantages of manipulating at your own infra edge or performance boosts, sure does come in handy!
We did this on production (still runs at webscale) but we abandoned dev effort on it for ${reasons}. I _loved_ it though :) Hook Lua on the HTTP event processing stages and add icing on the cake with Lua modules to hand-off non-trivial stuffs..
Safari for general browsing (and default) because it's the most energy efficient one.
Firefox for work. The best implementation of pinned tabs. Shame it's a resource hog.
Chrome for reference and research type stuff. No reason why Chrome, I just want that separate from other contexts.
Chrome Canary for development. Still a Chrome, the best browser for development, but I get to separate all the reference stuff nicely from actual Chrome
Brave for streaming, because it's still a Chrome (so supports all the things) and blocks video ads really well.
Tor for... nice try, FBI. :)
I set up iTerm to open up reference type links I care about in Chrome, and all the other ones in Safari.
Don't hesitate to charge for v2, if improvements pile up and you have affordances to do so. Will gladly pay.
It's pretty great already as-is. Thank you.