diff --git a/Development/Hake/RunHake.hs b/Development/Hake/RunHake.hs
--- a/Development/Hake/RunHake.hs
+++ b/Development/Hake/RunHake.hs
@@ -28,10 +28,10 @@
 import System.FilePath            (takeFileName)
 import System.Process             (runProcess, waitForProcess)
 import Control.Monad              (when)
-import Control.Monad.Tools        (unlessM)
+import Control.Monad.Tools        (unlessM, filterM)
 import Data.Function.Tools        (applyWhen, apply2way)
 import YJTools.Tribial            (ghcMake, updateFile)
-import Text.RegexPR               (gsubRegexPR)
+import Text.RegexPR               (gsubRegexPR, ggetbrsRegexPR)
 import Development.Hake.Variables (defaultTrgtStr, hakefileUpdateOption,
                                    hakeDir, commentPair, srcSuffix, exeEscPairs)
 
@@ -47,8 +47,15 @@
                $ apply2way (updateFile commentPair) id $
 			                            (hakeDir ++) . takeFileName
   hakefileUD  <- updateFile commentPair src binSrc
+  modUD <-
+    if null othrs
+       then do mods <- getModules src
+               fmap or $ flip mapM mods
+                       $ apply2way (updateFile commentPair) id $
+	                                                    (hakeDir ++)
+       else return False
   notUpdated  <- doesNotExistOrOldThan binPath binSrc
-  when (othrsUD || hakefileUD || notUpdated) $ do
+  when (othrsUD || hakefileUD || notUpdated || modUD) $ do
     ec <- ghcMake bin hakeDir
     when (ec /= ExitSuccess) $ exitWith ec
   let args_  = applyWhen (othrsUD || hakefileUD) (hakefileUpdateOption:) $
@@ -59,3 +66,10 @@
 errorNotExist :: FilePath -> IO ()
 errorNotExist fp = unlessM (doesFileExist fp) $
                      error $ "runHake: " ++ fp ++ " does not exist"
+
+getModules :: FilePath -> IO [ FilePath ]
+getModules hf = do
+  cont <- readFile hf
+  let mods_ = map (!!1) $ ggetbrsRegexPR "^import\\s+([^\n\\([:blank:]]+)" cont
+  mods <- filterM doesFileExist $ map (++".hs") mods_
+  return mods
diff --git a/hake.cabal b/hake.cabal
--- a/hake.cabal
+++ b/hake.cabal
@@ -1,5 +1,5 @@
 Name:		hake
-Version:	1.0
+Version:	1.1
 License:	GPL
 License-file:	LICENSE
 Author:		Yoshikuni Jujo
@@ -69,5 +69,5 @@
 
 Executable hake
   GHC-Options:		-Wall
-  Build-Depends:	directory, process, yjtools >= 0.9.6, regexpr >= 0.3
+  Build-Depends:	directory, process, yjtools >= 0.9.7, regexpr >= 0.5.1
   Main-Is:		Main.hs