It looks like the last bullet point on the page, so I'm not surprised that you missed it. They could definitely put this farther up the page:

"Wren is a scripting language. Wren is intended for embedding in applications. It has no dependencies, a small standard library, and an easy-to-use C API. It compiles cleanly as C99, C++98 or anything later."

http://munificent.github.io/wren/