[akkartik]

Author here. I read your comment and just think I'm not a very good writer. Layers are absolutely not about adding extension points, and layers have nothing to do with modules with fixed interfaces. Often when I want to extend behavior in my layered programs, I just modify the line in place.

I mentioned a couple of rules of thumb for when I create new layers here: https://news.ycombinator.com/item?id=21766557#21767499

Here's the entry point for my current project which uses layers: http://akkartik.github.io/mu/html/000organization.cc.html

You can find a list of layers here: https://akkartik.github.io/mu1 (URL is slightly different; it's a previous prototype. But should suffice for this thread.)