[I retract this comment entirely—see downthread where rewq4321 corrects me.]
> on top of the "coming soon" filesystem/block store api
I’m completely unimpressed by Origin Private File Systems, which I believe is what you’re talking about: it’s just a key-value store, just made to look a little like a file system, but is probably exactly equivalent to IndexedDB in capability and usefulness, quite easily perfectly polyfillable atop it. It is certainly completely unsuitable for building a database on top of as far as ACID transactions or such are concerned—you’ll get appalling write performance because you will have to close the file to commit each write.
I wrote more about this in the thread about Safari having implemented OPFS five months ago: https://news.ycombinator.com/item?id=30394737. (My use of “probably” above is explained in there too.)
> on top of the "coming soon" filesystem/block store api
I’m completely unimpressed by Origin Private File Systems, which I believe is what you’re talking about: it’s just a key-value store, just made to look a little like a file system, but is probably exactly equivalent to IndexedDB in capability and usefulness, quite easily perfectly polyfillable atop it. It is certainly completely unsuitable for building a database on top of as far as ACID transactions or such are concerned—you’ll get appalling write performance because you will have to close the file to commit each write.
I wrote more about this in the thread about Safari having implemented OPFS five months ago: https://news.ycombinator.com/item?id=30394737. (My use of “probably” above is explained in there too.)