diff --git a/NgxExport/Tools/EDE.hs b/NgxExport/Tools/EDE.hs
--- a/NgxExport/Tools/EDE.hs
+++ b/NgxExport/Tools/EDE.hs
@@ -36,7 +36,6 @@
 #endif
 import qualified Data.HashMap.Strict as HM
 import           Data.HashMap.Strict (HashMap)
-import qualified Data.ByteString as B
 import           Data.ByteString (ByteString)
 import qualified Data.ByteString.Char8 as C8
 import qualified Data.ByteString.Lazy as L
@@ -69,14 +68,12 @@
 --
 -- ==== File /test_tools_extra_ede.hs/
 -- @
--- {-\# OPTIONS_GHC -Wno-unused-imports \#-}
---
 -- {-\# LANGUAGE TemplateHaskell \#-}
 --
 -- module TestToolsExtraEDE where
 --
 -- import           NgxExport
--- import           NgxExport.Tools.EDE
+-- import           NgxExport.Tools.EDE ()
 --
 -- import           Data.ByteString (ByteString)
 -- import qualified Data.ByteString.Lazy as L
@@ -92,8 +89,8 @@
 -- cookies. Notice that we are not using any Haskell declarations from module
 -- /NgxExport.Tools.EDE/ while still need to import this to access the three
 -- handlers from the Nginx configuration. This situation is quite valid though
--- not usual to /ghc/, and to make it keep silence, pragma
--- /OPTIONS_GHC -Wno-unused-imports/ was added on the top of the file.
+-- not usual to /ghc/, and to make it keep silence, an explicit empty import
+-- list was added at the end of the import stanza.
 --
 -- ==== File /nginx.conf/
 -- @
@@ -209,7 +206,7 @@
 -- > User id: user1, options: WyJvcDEiLCJvcDIiXQ==, path: %2Fopt%2Fusers
 
 type InputTemplates = (FilePath, [(ByteString, ByteString)])
-type Templates = HashMap B.ByteString (Result Template)
+type Templates = HashMap ByteString (Result Template)
 
 newtype EDERenderError = EDERenderError String
 
diff --git a/NgxExport/Tools/Subrequest.hs b/NgxExport/Tools/Subrequest.hs
--- a/NgxExport/Tools/Subrequest.hs
+++ b/NgxExport/Tools/Subrequest.hs
@@ -472,9 +472,8 @@
 -- The same as 'makeSubrequest' except it returns a binary encoded response data
 -- whose parts must be extracted by handlers made of
 -- 'extractStatusFromFullResponse', 'extractHeaderFromFullResponse', and
--- 'extractBodyFromFullResponse'.
---
--- Exported on the Nginx level by a handler of the same name.
+-- 'extractBodyFromFullResponse'. Exported on the Nginx level by handler
+-- /makeSubrequestFull/.
 makeSubrequestFull
     :: ByteString       -- ^ Subrequest configuration
     -> IO L.ByteString
@@ -489,9 +488,8 @@
 -- The same as 'makeSubrequestWithRead' except it returns a binary encoded
 -- response data whose parts must be extracted by handlers made of
 -- 'extractStatusFromFullResponse', 'extractHeaderFromFullResponse', and
--- 'extractBodyFromFullResponse'.
---
--- Exported on the Nginx level by a handler of the same name.
+-- 'extractBodyFromFullResponse'. Exported on the Nginx level by handler
+-- /makeSubrequestFullWithRead/.
 makeSubrequestFullWithRead
     :: ByteString       -- ^ Subrequest configuration
     -> IO L.ByteString
@@ -503,11 +501,12 @@
 
 -- | Extracts the HTTP status from an encoded response.
 --
--- Must be used to extract response data encoded by 'makeSubrequestFull' and
--- 'makeSubrequestFullWithRead'.
---
--- Exported on the Nginx level by a handler of the same name.
-extractStatusFromFullResponse :: ByteString -> L.ByteString
+-- Must be used to extract response data encoded by 'makeSubrequestFull' or
+-- 'makeSubrequestFullWithRead'. Exported on the Nginx level by handler
+-- /extractStatusFromFullResponse/.
+extractStatusFromFullResponse
+    :: ByteString       -- ^ Encoded HTTP response
+    -> L.ByteString
 extractStatusFromFullResponse = C8L.pack . show .
     (\(a, _, _) -> a) . (Binary.decode @FullResponse) . L.fromStrict
 
@@ -515,13 +514,17 @@
 
 -- | Extracts a specified header from an encoded response.
 --
--- Must be used to extract response data encoded by 'makeSubrequestFull' and
--- 'makeSubrequestFullWithRead'. Expects that the encoded response data is
--- attached after the name of the header and a vertical bar such as
--- /Header-Name|$hs_body/. The lookup of the header name is case-insensitive.
+-- Must be used to extract response data encoded by 'makeSubrequestFull' or
+-- 'makeSubrequestFullWithRead'. Exported on the Nginx level by handler
+-- /extractHeaderFromFullResponse/.
 --
--- Exported on the Nginx level by a handler of the same name.
-extractHeaderFromFullResponse :: ByteString -> L.ByteString
+-- Expects that the encoded response data is attached after the name of the
+-- header and a vertical bar such as /Header-Name|$hs_body/. The lookup of the
+-- header name is case-insensitive. Returns an empty value if the header was not
+-- found.
+extractHeaderFromFullResponse
+    :: ByteString       -- ^ Encoded HTTP response
+    -> L.ByteString
 extractHeaderFromFullResponse v =
     let (h, b) = mk *** C8.tail $ C8.break ('|' ==) v
         hs = (\(_, a, _) -> map (first mk) a) $
@@ -532,11 +535,12 @@
 
 -- | Extracts the body from an encoded response.
 --
--- Must be used to extract response data encoded by 'makeSubrequestFull' and
--- 'makeSubrequestFullWithRead'.
---
--- Exported on the Nginx level by a handler of the same name.
-extractBodyFromFullResponse :: ByteString -> L.ByteString
+-- Must be used to extract response data encoded by 'makeSubrequestFull' or
+-- 'makeSubrequestFullWithRead'. Exported on the Nginx level by handler
+-- /extractBodyFromFullResponse/.
+extractBodyFromFullResponse
+    :: ByteString       -- ^ Encoded HTTP response
+    -> L.ByteString
 extractBodyFromFullResponse =
     (\(_, _, a) -> a) . (Binary.decode @FullResponse) . L.fromStrict
 
diff --git a/ngx-export-tools-extra.cabal b/ngx-export-tools-extra.cabal
--- a/ngx-export-tools-extra.cabal
+++ b/ngx-export-tools-extra.cabal
@@ -1,5 +1,5 @@
 name:                       ngx-export-tools-extra
-version:                    0.4.1.0
+version:                    0.4.1.1
 synopsis:                   More extra tools for Nginx haskell module
 description:                More extra tools for
         <https://github.com/lyokha/nginx-haskell-module Nginx haskell module>.