This issue is dedicated to the metacircular interpreter. If you have never experienced the magic of metacircularity for yourself, please take this opportunity.

Basically, what we mean when we say "metacircular interpreter" is an interpreter written in itself. Typically, the implementation language is simplified to only a few forms and functions. For instance, Lisp can be written using only seven primitive operations. That is pretty good. A metacircular object system can be written using a single point of circularity!

Metacircularity is important for two reasons: it empowers an individual to bootstrap a large system from a small system and it allows for runtime reflection (querying and modification of runtime behavior). The most powerful computer systems in the world have used metacircularity, including Lisp, Smalltalk, and Forth.