Plucene is a fully-featured and highly customizable search engine
toolkit based on the Lucene API.

It is not, in and of itself, a functional search engine - you are
expected to subclass and tie all the pieces together to suit your own
needs. The synopsis above gives a rough indication of how to use the
engine in simple cases. See Plucene::Simple in the distribution for one
example of tying it all together.