Guile in a closed environment

[marker@kelp.boston.ma.us (Mark E. Roland)]

(I hope this is the right address for this type of question.
All I know about Guile is what I've seen in the GNU's Bulletin.)

I have a server that accepts certain requests by email, and
one such request requires a sufficiently rich format that it
needs a sublanguage, so that the client can submit a short
function and the server will evaluate it.  But since access to
the server is unrestricted, the server has to be able to evaluate
the function in a closed environment; in particular, with no
access to system calls.  Does it make sense to use Guile for this?
(If not, then I'll probably end up writing my own simple extension
language, probably based on Lisp.)