The `sssss` program might have a potential. But let me give you an example: I want my every blog article to also have versions / revisions and I'd like visitors to be able to read the older versions as well as the last version.

I'd also like multilingual article ability (but I think some of the engines out there can do that). The more I think of it, the more I wonder if it should be something like Ghost.org: namely backed by sqlite and not naked files. But who knows.