diff --git a/hakyll.cabal b/hakyll.cabal
--- a/hakyll.cabal
+++ b/hakyll.cabal
@@ -1,5 +1,5 @@
 Name:    hakyll
-Version: 3.2.0.6
+Version: 3.2.0.7
 
 Synopsis: A static website compiler library
 Description:
diff --git a/src/Hakyll/Core/Compiler.hs b/src/Hakyll/Core/Compiler.hs
--- a/src/Hakyll/Core/Compiler.hs
+++ b/src/Hakyll/Core/Compiler.hs
@@ -98,6 +98,7 @@
     , getRouteFor
     , getResourceString
     , getResourceLBS
+    , getResourceWith
     , fromDependency
     , require_
     , require
diff --git a/src/Hakyll/Core/Resource/Provider.hs b/src/Hakyll/Core/Resource/Provider.hs
--- a/src/Hakyll/Core/Resource/Provider.hs
+++ b/src/Hakyll/Core/Resource/Provider.hs
@@ -23,6 +23,7 @@
 import Data.Map (Map)
 import qualified Data.Map as M
 
+import Data.Time (UTCTime)
 import qualified Crypto.Hash.MD5 as MD5
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Lazy as LB
@@ -34,13 +35,15 @@
 --
 data ResourceProvider = ResourceProvider
     { -- | A list of all resources this provider is able to provide
-      resourceList          :: [Resource]
+      resourceList             :: [Resource]
     , -- | Retrieve a certain resource as string
-      resourceString        :: Resource -> IO String
+      resourceString           :: Resource -> IO String
     , -- | Retrieve a certain resource as lazy bytestring
-      resourceLBS           :: Resource -> IO LB.ByteString
+      resourceLBS              :: Resource -> IO LB.ByteString
+    , -- | Check when a resource was last modified
+      resourceModificationTime :: Resource -> IO UTCTime
     , -- | Cache keeping track of modified items
-      resourceModifiedCache :: MVar (Map Resource Bool)
+      resourceModifiedCache    :: MVar (Map Resource Bool)
     }
 
 -- | Create a resource provider
@@ -48,8 +51,9 @@
 makeResourceProvider :: [Resource]                      -- ^ Resource list
                      -> (Resource -> IO String)         -- ^ String reader
                      -> (Resource -> IO LB.ByteString)  -- ^ ByteString reader
+                     -> (Resource -> IO UTCTime)        -- ^ Time checker
                      -> IO ResourceProvider             -- ^ Resulting provider
-makeResourceProvider l s b = ResourceProvider l s b <$> newMVar M.empty
+makeResourceProvider l s b t = ResourceProvider l s b t <$> newMVar M.empty
 
 -- | Check if a given identifier has a resource
 --
diff --git a/src/Hakyll/Core/Resource/Provider/File.hs b/src/Hakyll/Core/Resource/Provider/File.hs
--- a/src/Hakyll/Core/Resource/Provider/File.hs
+++ b/src/Hakyll/Core/Resource/Provider/File.hs
@@ -6,6 +6,10 @@
 
 import Control.Applicative ((<$>))
 
+import Data.Time (readTime)
+import System.Directory (getModificationTime)
+import System.Locale (defaultTimeLocale)
+import System.Time (formatCalendarTime, toCalendarTime)
 import qualified Data.ByteString.Lazy as LB
 
 import Hakyll.Core.Resource
@@ -22,3 +26,9 @@
         getRecursiveContents False "."
     makeResourceProvider list (readFile . unResource)
                               (LB.readFile . unResource)
+                              mtime
+  where
+    mtime (Resource r) = do
+        ct <- toCalendarTime =<< getModificationTime r
+        let str = formatCalendarTime defaultTimeLocale "%s" ct
+        return $ readTime defaultTimeLocale "%s" str
diff --git a/src/Hakyll/Web/Page/Metadata.hs b/src/Hakyll/Web/Page/Metadata.hs
--- a/src/Hakyll/Web/Page/Metadata.hs
+++ b/src/Hakyll/Web/Page/Metadata.hs
@@ -12,6 +12,8 @@
     , copyField
     , renderDateField
     , renderDateFieldWith
+    , renderModificationTime
+    , renderModificationTimeWith
     , copyBodyToField
     , copyBodyFromField
     ) where
@@ -31,6 +33,7 @@
 import Hakyll.Core.Util.String
 import Hakyll.Core.Identifier
 import Hakyll.Core.Compiler
+import Hakyll.Core.Resource.Provider
 
 -- | Get a metadata field. If the field does not exist, the empty string is
 -- returned.
@@ -150,6 +153,28 @@
                           "%Y-%m-%d"
                           dateString :: Maybe UTCTime
         return $ formatTime locale format time
+
+-- | Set the modification time as a field in the page
+--
+renderModificationTime :: String
+                       -- ^ Destination key
+                       -> String
+                       -- ^ Format to use on the time
+                       -> Compiler (Page String) (Page String)
+                       -- ^ Resulting compiler
+renderModificationTime = renderModificationTimeWith defaultTimeLocale
+
+renderModificationTimeWith :: TimeLocale
+                           -- ^ Output time locale
+                           -> String
+                           -- ^ Destination key
+                           -> String
+                           -- ^ Format to use on the time
+                           -> Compiler (Page String) (Page String)
+                           -- ^ Resulting compiler
+renderModificationTimeWith locale key format =
+    id &&& (getResource >>> getResourceWith resourceModificationTime) >>>
+    setFieldA key (arr (formatTime locale format))
 
 -- | Copy the body of a page to a metadata field
 --