Alex Bronstein (aka effulgentsia) talks about how he got working with Drupal 7 and the Form API through his work on the flexifield module. He's also listed as the co-maintainer of the AJAX, Form, Render, and Theme systems for Drupal 7. Bronstein also talks about some of the work that he has done with Libraries through Your Library Site and mentions the Social Online Public Access Catalog (SOPAC) module.