NationBuilder is hiring developers and organizers. We build tools for leaders, mostly focused on politics right now. We're backed by Andreessen Horowitz, Sean Parker, and many others.
Developer jobs: http://dev.nationbuilder.com/jobs Organizer jobs: http://nationbuilder.com/organizer
Our stack is Ruby/Rails/Postgres/Redis/Mongo, details here: http://dev.nationbuilder.com/about