e actors' guild was able to put on a spectacular theatrical production. This is

truly impressive, since the guild operates on a shoestring.

What is the meaning of the expression on a shoestring?
out of the public eye
up on a tightrope
with very little money

The meaning of the expression "on a shoestring" in this context is with very little money. It indicates that the actors' guild operates with limited financial resources but was still able to put on a remarkable theatrical production.