Yes, and it's a very nice tutorial! I'm interested in implementation details. Maybe there's no hygiene (and no scope sets etc.) to worry about—that would probably make documentation a little shorter. I'm sure the documentation will grow as people run into edge cases.
(I'm also probably a little spoiled with documentation coming from Racket which has like 4 big chapters dedicated to different aspects of macros scattered around the docs, plus some associated papers. Forgive me—I'm not trying to dunk on Hy; I just like reading docs.)
Admittedly, I've tried not to document the implementation. Yeah, they're pretty much simple dirty Common Lisp macros. Internally, they're functions that are called with the arguments converted to models (via `hy.as-model`), and then the return value is converted to a model. If a macro's first parameter is named `_hy_compiler`, it gets access to the current compiler object; this is undocumented since it's only meant for internal use. Reader macros have no parameters, but can access the current reader object as `&reader`. When it's defined, a reader macro is added to the current reader's dispatch table.
(I'm also probably a little spoiled with documentation coming from Racket which has like 4 big chapters dedicated to different aspects of macros scattered around the docs, plus some associated papers. Forgive me—I'm not trying to dunk on Hy; I just like reading docs.)