Yeah, I'm also surprised to see people so upset about the idea of the feature mostly for the argument that it doesn't presently exist. As for the compile-time-extension, my main concern with that as a free software project is that we try to play nice with distro packaging and requiring users to compile their own sqlite would be setting them up for a bit of pain. But I suspect it doesn't matter: if the feature was coded with the aim of pushing it upstream, I'm suspecting there's a good chance upstream would accept it if of good quality.

Then again, I'm not upstream. :)