diff --git a/Control/Shell.hs b/Control/Shell.hs
--- a/Control/Shell.hs
+++ b/Control/Shell.hs
@@ -128,6 +128,7 @@
 --   current name.
 cpdir :: FilePath -> FilePath -> Shell ()
 cpdir fromdir todir = do
+    assert ("`" ++ fromdir ++ "' is not a directory") (isDirectory fromdir)
     exists <- isDirectory todir
     if exists
       then do
diff --git a/Control/Shell/Download.hs b/Control/Shell/Download.hs
--- a/Control/Shell/Download.hs
+++ b/Control/Shell/Download.hs
@@ -1,53 +1,84 @@
--- | Shellmate wrapper for @download-curl@.
-module Control.Shell.Download (
-    URI,
-    fetch, fetchBytes,
-    fetchFile,
-    fetchTags, fetchXML, fetchFeed
+{-# LANGUAGE OverloadedStrings, CPP #-}
+-- | High level functions for downloading files.
+module Control.Shell.Download
+  ( URI
+  , fetch, fetchBytes
+  , fetchFile
+#if DOWNLOAD_EXTRAS
+  , fetchTags, fetchXML, fetchFeed
+#endif
   ) where
 import Data.ByteString as BS (ByteString, writeFile)
-import Network.Curl.Download as C
-import Text.HTML.TagSoup (Tag)
-import Text.XML.Light.Types (Content)
+import Data.String
+import Network.HTTP
+import qualified Network.URI as U
+#if DOWNLOAD_EXTRAS
+import Text.Feed.Import (parseFeedString)
 import Text.Feed.Types (Feed)
+import Text.HTML.TagSoup (Tag, parseTags)
+import Text.XML.Light (Content, parseXML)
+#endif
 import Control.Shell
 
 -- | A Uniform Resource Locator.
 type URI = String
 
-liftE :: IO (Either String a) -> Shell a
+liftE :: Show e => IO (Either e a) -> Shell a
 liftE m = do
   res <- liftIO m
   case res of
-    Left e  -> fail e
+    Left e  -> fail (show e)
     Right x -> return x
 
+httpFail :: (Int, Int, Int) -> String -> Shell a
+httpFail (a,b,c) reason =
+  fail $ "HTTP error " ++ concat [show a, show b, show c] ++ ": " ++ reason
+
+fetchSomething :: (IsString a, HStream a) => URI -> Shell a
+fetchSomething uri = do
+    u <- assert ("could not parse URI `" ++ uri ++ "'") (U.parseURI uri)
+    rsp <- liftE $ simpleHTTP (req u)
+    case rspCode rsp of
+      (2,_,_) -> return (rspBody rsp)
+      code    -> httpFail code (rspReason rsp)
+  where
+    req u = Request {
+        rqURI = u,
+        rqMethod = GET,
+        rqHeaders = [],
+        rqBody = ""
+      }
+
 -- | Download content specified by a url using curl, returning the content
 --   as a strict 'ByteString'.
 fetchBytes :: URI -> Shell ByteString
-fetchBytes = liftE . C.openURI
+fetchBytes = fetchSomething
 
 -- | Download content specified by a url using curl, returning the content
 --   as a 'String'.
 fetch :: URI -> Shell String
-fetch = liftE . C.openURIString
+fetch = fetchSomething
 
 -- | Download content specified by a url using curl, writing the content to
 --   the file specified by the given 'FilePath'.
 fetchFile :: FilePath -> URI -> Shell ()
 fetchFile file = fetchBytes >=> liftIO . BS.writeFile file
 
+#if DOWNLOAD_EXTRAS
 -- | Download the content as for 'fetch', but return it as a list of parsed
 --   tags using the tagsoup html parser.
 fetchTags :: URI -> Shell [Tag String]
-fetchTags = liftE . C.openAsTags
+fetchTags = fmap parseTags . fetch
 
 -- | Download the content as for 'fetch', but return it as parsed XML, using
 --   the xml-light parser.
 fetchXML :: URI -> Shell [Content]
-fetchXML = liftE . C.openAsXML
+fetchXML = fmap parseXML . fetch
 
 -- | Download the content as for 'fetch', but return it as as parsed RSS or
 --   Atom content, using the feed library parser.
 fetchFeed :: URI -> Shell Feed
-fetchFeed = liftE . C.openAsFeed
+fetchFeed uri = do
+  str <- fetch uri
+  assert ("could not parse feed from `" ++ uri ++ "'") (parseFeedString str)
+#endif
diff --git a/shellmate.cabal b/shellmate.cabal
--- a/shellmate.cabal
+++ b/shellmate.cabal
@@ -1,5 +1,5 @@
 name:                shellmate
-version:             0.2.2
+version:             0.2.3
 synopsis:            Simple interface for shell scripting in Haskell.
 description:         Aims to simplify development of cross-platform shell scripts and similar things.
 homepage:            http://github.com/valderman/shellmate
@@ -17,6 +17,10 @@
     type:       git
     location:   https://github.com/valderman/shellmate.git
 
+flag download-extras
+    default: True
+    description: Build Control.Shell.Download with extras for parsing downloaded HTML, XML, RSS and Atom feeds.
+    
 library
   exposed-modules:
     Control.Shell
@@ -26,16 +30,23 @@
     Control.Shell.Handle
     Control.Shell.Internal
   build-depends:
-    base          >=4.7  && <5,
-    transformers  >=0.3  && <0.5,
-    download-curl >=0.1  && <0.2,
-    feed          >=0.3  && <0.4,
-    tagsoup       >=0.13 && <0.14,
-    xml           >=1.3  && <1.4,
-    bytestring    >=0.10 && <0.11,
-    filepath      >=1.3  && <1.5,
-    process       >=1.1  && <1.5,
-    directory     >=1.1  && <1.3,
-    temporary     >=1.1  && <1.3
+    base         >=4.7    && <5,
+    transformers >=0.3    && <0.5,
+    bytestring   >=0.10   && <0.11,
+    filepath     >=1.3    && <1.5,
+    process      >=1.1    && <1.5,
+    directory    >=1.1    && <1.3,
+    temporary    >=1.1    && <1.3,
+    -- for Control.Shell.Download
+    HTTP         >=4000.2 && <4000.3,
+    network-uri  >=2.6    && <2.7
+
+  if flag(download-extras)
+    build-depends:            
+      feed    >=0.3    && <0.4,
+      tagsoup >=0.13   && <0.14,
+      xml     >=1.3    && <1.4
+    cpp-options:
+      -DDOWNLOAD_EXTRAS=1
   ghc-options:
     -Wall