  We describe a complete Scheme implementation of miniAdapton, which implements
the core functionality of the Adapton system for incremental computation (also
known as self-adjusting computation). Like Adapton, miniAdapton allows
programmers to safely combine mutation and memoization. miniAdapton is built on
top of an even simpler system, microAdapton. Both miniAdapton and microAdapton
are designed to be easy to understand, extend, and port to host languages other
than Scheme. We also present adapton variables, a new interface in Adapton for
variables intended to represent expressions.
