diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,11 @@
 Changes
 =======
 
+Version 0.11.0.1
+----------------
+
+Use monotonic clock when measuring durations.
+
 Version 0.11
 ------------
 
diff --git a/Test/Tasty/Run.hs b/Test/Tasty/Run.hs
--- a/Test/Tasty/Run.hs
+++ b/Test/Tasty/Run.hs
@@ -11,7 +11,6 @@
 import qualified Data.Sequence as Seq
 import qualified Data.Foldable as F
 import Data.Maybe
-import Data.Time.Clock.POSIX
 import Control.Monad.State
 import Control.Monad.Writer
 import Control.Monad.Reader
@@ -22,6 +21,7 @@
 import Control.Applicative
 import Control.Arrow
 import GHC.Conc (labelThread)
+import qualified System.Clock as Clock
 
 import Test.Tasty.Core
 import Test.Tasty.Parallel
@@ -296,6 +296,12 @@
   end   <- getTime
   return (end-start, r)
 
--- | Get system time
+-- | Get monotonic time
+--
+-- Warning: This is not the system time, but a monotonically increasing time
+-- that facilitates reliable measurement of time differences.
 getTime :: IO Time
-getTime = realToFrac <$> getPOSIXTime
+getTime = do
+  t <- Clock.getTime Clock.Monotonic
+  let ns = realToFrac $ Clock.timeSpecAsNanoSecs t
+  return $ ns / 10^9
diff --git a/tasty.cabal b/tasty.cabal
--- a/tasty.cabal
+++ b/tasty.cabal
@@ -2,7 +2,7 @@
 --  see http://haskell.org/cabal/users-guide/
 
 name:                tasty
-version:             0.11
+version:             0.11.0.1
 synopsis:            Modern and extensible testing framework
 description:         Tasty is a modern testing framework for Haskell.
                      It lets you combine your unit tests, golden
@@ -59,7 +59,7 @@
     unbounded-delays >= 0.1,
     async >= 2.0,
     ansi-terminal >= 0.6.2,
-    time >= 1.4
+    clock >= 0.4.4.0
 
   if impl(ghc < 7.6)
     -- for GHC.Generics