Very cool. Reminds me of Heroku's Data Clip [1] service released as part of their Postgres as a service offering. [1] https://postgres.heroku.com/blog/past/2012/1/31/simple_data_...
If you're already using Heroku Postgres there's a ton of overlap between the services, but I'm hoping to provide a decent open source alternative for the rest of us. :)