You see, Heroku runs PostgreSQL for each rails application database. They’re running a version new enough (Version 8.3) to have full text index support built in. If we’re willing to throw out database agnosticism, we can take advantage of the database’s indexing capability.

HireFire has the ability to automatically scale your web and worker dynos up and down when necessary. When new jobs are queued in to your application's worker queue (Delayed Job, Resque), HireFire will spin up new worker dynos to process these jobs. When the queue is empty, HireFire will shut down the worker dynos again so you're not paying for idle workers.