Build your own async primitive
Concurrency isn't easy and implementing its primitives is even harder. I found myself in need of
some no-std, no-alloc Rust async concurrency primitives and decided to write some. I kept the
scope small so even you and I can understand it. Even so, it still involved futures, wakers,
atomics, drop and unsafe. I'll introduce each of those to you while building a simple primitive.
At the end, you will be able to implement your own primitives!
