diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,8 @@
+### 1.0.1
+
+- Using deepseq for really deep evaluation of resulting lazy bytestrings to
+  prevent leaks of exceptions outside of protected code.
+
 ### 1.0
 
 - Added an asynchronous content handler exported with *ngxExportAsyncHandler*.
diff --git a/NgxExport.hs b/NgxExport.hs
--- a/NgxExport.hs
+++ b/NgxExport.hs
@@ -52,6 +52,7 @@
 import           System.Posix.Internals
 import           Control.Monad
 import           Control.Monad.Loops
+import           Control.DeepSeq
 import qualified Control.Exception as E
 import           Control.Exception hiding (Handler)
 import           GHC.IO.Exception (ioe_errno)
@@ -304,7 +305,7 @@
        Ptr CString -> Ptr CSize -> Ptr CInt -> IO CUInt|]
 
 -- | Exports a function of type
--- /'B.ByteString' -> IO ('L.ByteString', 'B.ByteString', 'Int')/
+-- /'B.ByteString' -> 'IO' ('L.ByteString', 'B.ByteString', 'Int')/
 -- for using in directive /haskell_async_content/.
 --
 -- The first element in the returned /3-tuple/ of the exported function is
@@ -463,7 +464,7 @@
 yY f x (I n) p pl spd = do
     (s, (r, _)) <- safeYYHandler $ do
         s <- f <$> B.unsafePackCStringLen (x, n)
-        fmap (flip (,) (0, False)) $ return $! s
+        fmap (flip (,) (0, False)) $ return $!! s
     pokeLazyByteString s p pl spd
     return r
 
@@ -473,7 +474,7 @@
 ioyY f x (I n) p pl spd = do
     (s, (r, _)) <- safeYYHandler $ do
         s <- B.unsafePackCStringLen (x, n) >>= flip f False
-        fmap (flip (,) (0, False)) $ return $! s
+        fmap (flip (,) (0, False)) $ return $!! s
     pokeLazyByteString s p pl spd
     return r
 
@@ -491,7 +492,7 @@
     (do
         (s, (r, exiting)) <- safeYYHandler $ do
             (s, exiting) <- a
-            fmap (flip (,) (0, exiting)) $ return $! s
+            fmap (flip (,) (0, exiting)) $ return $!! s
         pokeLazyByteString s p pl spd
         poke pr r
         if exiting
@@ -561,7 +562,7 @@
     (do
         x' <- B.unsafePackCStringLen (x, n)
         (s, ct, I st) <- f x'
-        (return $! s) >> pokeContentTypeAndStatus ct pct plct pst st
+        (return $!! s) >> pokeContentTypeAndStatus ct pct plct pst st
         newStablePtr ct >>= poke spct
         return (s, False)
     ) fd efd
@@ -605,7 +606,7 @@
 handler f x (I n) p pl pct plct spct pst spd =
     safeHandler pct pst $ do
         (s, ct, I st) <- f <$> B.unsafePackCStringLen (x, n)
-        pokeContentTypeAndStatus ct pct plct pst st
+        (return $!! s) >> pokeContentTypeAndStatus ct pct plct pst st
         pokeLazyByteString s p pl spd
         newStablePtr ct >>= poke spct
         return 0
@@ -624,7 +625,7 @@
 unsafeHandler f x (I n) p pl pct plct pst =
     safeHandler pct pst $ do
         (s, ct, I st) <- f <$> B.unsafePackCStringLen (x, n)
-        pokeContentTypeAndStatus ct pct plct pst st
+        (return $!! s) >> pokeContentTypeAndStatus ct pct plct pst st
         PtrLen t l <- B.unsafeUseAsCStringLen s return
         pokeCStringLen t l p pl
         return 0
diff --git a/ngx-export.cabal b/ngx-export.cabal
--- a/ngx-export.cabal
+++ b/ngx-export.cabal
@@ -1,5 +1,5 @@
 name:                       ngx-export
-version:                    1.0
+version:                    1.0.1
 synopsis:                   Helper module for Nginx haskell module
 description:                Helper module for
         <http://github.com/lyokha/nginx-haskell-module Nginx haskell module>
@@ -20,6 +20,7 @@
                           , template-haskell
                           , bytestring >= 0.10.0.0
                           , monad-loops >= 0.4.2
+                          , deepseq >= 1.2.0.0
                           , binary >= 0.8.1.0
                           , async >= 2.0
                           , unix