In 2001, Will Estes took over as maintainer of flex.

John Millaway is a co-author of the current version of flex. He has
contributed a large number of new features, fixed a large number of
outstanding bugs and has made significant contributions to the flex
documentation.

Aaron Stone has contributed several bug fixes to the flex codebase.

Vern Paxson wrote flex with the help of many ideas and much
inspiration from Van Jacobson.  Original version by Jef Poskanzer.

The fast table representation is a partial implementation of a design
done by Van Jacobson.  The implementation was done by Kevin Gong and
Vern Paxson.