Jennifer Lea Lampton has been actively building sites with Drupal and participating in the open-source community since 2006. She maintains several of her own modules, and contributes issues & patches to many other projects as it relates to the needs of her own, or her client's work.
Jen's primary focus for improving Drupal is to make things easier to use ("usability") and easier to learn ("learnability"). She is currently wrangling a ton of very awesome contributors to get Twig into Drupal 8 core.
Jen is a very active member in the Drupal community as well. She is the lead coordinator for the Bay Area Drupal Camp, and was also on the organizing committee for DrupalCon San Francisco in 2010. Jen is also a regular face at the Berkeley users group, an occasional attendee at the San Francisco users group, and drops in on other Drupal camps and conferences around the world.