  This paper presents Favalon, a functional programming language built on the
premise of a lambda calculus for use as an interactive shell replacement.
Favalon seamlessly integrates with typed versions of existing libraries and
commands using type inference, flexible runtime type metadata, and the same
techniques employed by shells to link commands together. Much of Favalon's
syntax is customizable via user-defined functions, allowing it to be extended
by anyone who is familiar with a command-line shell. Furthermore, Favalon's
type inference engine can be separated from its runtime library and easily
repurposed for other applications.
