twitter-util-async adapts the scala-async library, which only operates with scala.concurrent.Future, to operate with com.twitter.util.Future in the Twitter util library.

Just add the following dependency to your SBT configuration:

libraryDependencies += "com.foursquare" %% "twitter-util-async" % "1.0.0"

See the documentation for scala-async for information on how to use async and await. The main difference is that you must import com.foursquare.common.async.Async.{async, await} instead of scala.async.Async.{async, await}. (Also, obviously, async returns, and await expects, a com.twitter.util.Future instead of a scala.concurrent.Future.