POSIX time, if you need to deal with timestamps and the like. Most people won't need this module.

You can use POSIXTime to obtain integer/word timestamps. For example:

import Data.Time import Data.Time.Clock.POSIX import Data.Int nanosSinceEpoch :: UTCTime -> Int64 nanosSinceEpoch = floor . (1e9 *) . nominalDiffTimeToSeconds . utcTimeToPOSIXSeconds main :: IO () main = do u <- getCurrentTime print $ nanosSinceEpoch u