airbnb/synapse — pull request #85 by liamstewart (2014-08-05 18:11:59+00:00)
Title: Consider only running instances and memoize AWS calls.

It doesn't make sense to retrieve starting, stopping, stopped, and terminated instances
and include them on the server list. The `memoize` block ensures that results
from requests are remembered, avoiding redundant calls to retrieve instance
details.