diff --git a/Development/Shake/Core.hs b/Development/Shake/Core.hs
--- a/Development/Shake/Core.hs
+++ b/Development/Shake/Core.hs
@@ -36,7 +36,7 @@
 -- | Options to control the execution of Shake, usually specified by overriding fields in
 --   'shakeOptions':
 --
---   @ 'shakeOptions'{'shakeThreads'=4, 'shakeReport'=Just "report.html"} @
+--   @ 'shakeOptions'{'shakeThreads'=4, 'shakeReport'=Just \"report.html\"} @
 data ShakeOptions = ShakeOptions
     {shakeFiles :: FilePath -- ^ Where shall I store the database and journal files (defaults to @.shake@).
     ,shakeThreads :: Int -- ^ What is the maximum number of rules I should run in parallel (defaults to @1@).
diff --git a/Development/Shake/Database.hs b/Development/Shake/Database.hs
--- a/Development/Shake/Database.hs
+++ b/Development/Shake/Database.hs
@@ -333,7 +333,10 @@
 -- DATABASE
 
 withDatabase :: (String -> IO ()) -> FilePath -> Int -> (Database -> IO a) -> IO a
-withDatabase logger filename version = bracket (openDatabase logger filename version) closeDatabase
+withDatabase logger filename version act = do
+    -- expand the filename, in case pwd has changed by the close action
+    filename <- canonicalizePath filename
+    bracket (openDatabase logger filename version) closeDatabase act
 
 
 -- Files are named based on the FilePath, but with different extensions,
diff --git a/Development/Shake/Derived.hs b/Development/Shake/Derived.hs
--- a/Development/Shake/Derived.hs
+++ b/Development/Shake/Derived.hs
@@ -24,6 +24,26 @@
     when (res /= ExitSuccess) $
         error $ "System command failed:\n" ++ cmd
 
+
+-- | Execute a system command with a specified current working directory (first argument).
+--   This function will raise an error if the exit code is non-zero.
+--   Before running 'systemCwd' make sure you 'need' any required files.
+--
+-- > systemCwd "/usr/MyDirectory" "pwd" []
+systemCwd :: FilePath -> FilePath -> [String] -> Action ()
+systemCwd cwd path args = do
+    let path2 = toNative path
+    let cmd = unwords $ path2 : args
+    putLoud cmd
+    res <- traced ("system " ++ cmd) $ do
+        -- FIXME: Should I be using the non-exported System.Process.syncProcess?
+        --        That installs/removes signal handlers.
+        hdl <- runProcess path2 args (Just cwd) Nothing Nothing Nothing Nothing
+        waitForProcess hdl
+    when (res /= ExitSuccess) $
+        error $ "System command failed:\n" ++ cmd
+
+
 -- | Execute a system command, returning @(stdout,stderr)@.
 --   This function will raise an error if the exit code is non-zero.
 --   Before running 'systemOutput' make sure you 'need' any required files.
diff --git a/Development/Shake/Pool.hs b/Development/Shake/Pool.hs
--- a/Development/Shake/Pool.hs
+++ b/Development/Shake/Pool.hs
@@ -104,10 +104,17 @@
 runPool :: Int -> (Pool -> IO ()) -> IO () -- run all tasks in the pool
 runPool n act = do
     s <- newVar $ Just emptyS
-    res <- newBarrier
-    let pool = Pool n s res
-    addPool pool $ act pool
-    res <- waitBarrier res
-    case res of
-        Nothing -> return ()
-        Just e -> throw e
+    let cleanup = modifyVar_ s $ \s -> do
+            -- if someone kills our thread, make sure we kill our child threads
+            case s of
+                Just s -> mapM_ killThread $ Set.toList $ threads s
+                Nothing -> return ()
+            return Nothing
+    flip onException cleanup $ do
+        res <- newBarrier
+        let pool = Pool n s res
+        addPool pool $ act pool
+        res <- waitBarrier res
+        case res of
+            Nothing -> return ()
+            Just e -> throw e
diff --git a/Examples/Test/Pool.hs b/Examples/Test/Pool.hs
--- a/Examples/Test/Pool.hs
+++ b/Examples/Test/Pool.hs
@@ -50,7 +50,7 @@
             blockPool pool $ takeMVar var
             modifyMVar_ done $ const $ return True
     done <- readMVar done
-    assert done "Blocking works"
+    assert done "Blocking"
 
     -- check someone spawned when at zero todo still gets run
     done <- newMVar False
@@ -61,4 +61,20 @@
                 wait
                 modifyMVar_ done $ const $ return True
     done <- readMVar done
-    assert done "Waiting on someone works"
+    assert done "Waiting on someone"
+
+    -- check that killing a thread pool stops the tasks, bug 545
+    thread <- newEmptyMVar
+    done <- newEmptyMVar
+    res <- newMVar True
+    t <- forkIO $ finally (putMVar done ()) $ runPool 1 $ \pool ->
+        addPool pool $ do
+            t <- takeMVar thread
+            killThread t
+            wait -- allow the thread to die first
+            modifyMVar_ res (const $ return False)
+    putMVar thread t
+    takeMVar done
+    wait >> wait >> wait -- allow the bad thread to continue
+    res <- readMVar res
+    assert res "Early termination"
diff --git a/shake.cabal b/shake.cabal
--- a/shake.cabal
+++ b/shake.cabal
@@ -1,7 +1,7 @@
 cabal-version:      >= 1.6
 build-type:         Simple
 name:               shake
-version:            0.2.9
+version:            0.2.10
 license:            BSD3
 license-file:       LICENSE
 category:           Development