//! upstream libraries, no system libraries, and no libc.
//!
//! [^free]: Strictly speaking, there are some symbols which are needed but
-//! they aren't always neccesary.
+//! they aren't always necessary.
//!
//! The core library is *minimal*: it isn't even aware of heap allocation,
//! nor does it provide concurrency or I/O. These things require