Primitives

docs/primitives.md lists all 54, with what each one compiles to on the Web and on React Native and which conformance case pins it. It is generated — pnpm docs:primitives — by compiling one snippet per primitive through both backends, so it cannot describe a lowering the compiler does not do. Adding a primitive without a snippet or a doc comment fails rather than leaving a hole, and CI checks the page is current.

The half worth reading is where a role has to be written on one side and not the other: 17 of the 54. A <nav> is a navigation landmark because it is a <nav>; React Native has no elements, so every role it keeps is one the compiler put there — and the ones it has no word for are the ones genuinely lost.