I may be mixing this language up with another text-manipulation language starting with 'R' (not being coy—I genuinely don't remember its name), but I seem to remember being uncertain of the reach of this project.

The Wikipedia page links two publications by (I suppose) the creator of Ragel, and two publications that do not seem to be specifically about Ragel; and the product page mentions nothing in the way of publications or references to uses in industry. Is Ragel actually widely used?