lang/chicken - The NetBSD Packages Collection

CHICKEN is a Scheme-to-C compiler supporting most of the language
features as defined in the Revised^5 Report on Scheme.  CHICKEN
generates quite portable C code, and files compiled by it (including
itself) should work without any changes on most platforms.

The whole package is distributed under a BSD license and as such free
to use and modify as long as you adhere to its terms (see the manual).
Linkage to C modules and C-library functions is straightforward, so
it's easy to access C from Scheme.  Compiled code can be embedded into
existing C programs without problems.  The generated code supports
full tail-recursion, first-class continuations, multiple values and
dynamic-wind.