diff --git a/CabalDev.hs b/CabalDev.hs
index c7a32b1..a76485c 100644
--- a/CabalDev.hs
+++ b/CabalDev.hs
@@ -17,16 +17,24 @@ import Types
 modifyOptions :: Options -> IO Options
 modifyOptions opts = found ||> notFound
   where
-    found = addPath opts <$> findCabalDev
+    found = do
+        path <- findCabalDev (sandbox opts)
+        return $ addPath opts path
     notFound = return opts
 
-findCabalDev :: IO String
-findCabalDev = getCurrentDirectory >>= searchIt . splitPath
+findCabalDev :: Maybe String -> IO FilePath
+findCabalDev (Just path) = do
+    a <- doesDirectoryExist path
+    if a then
+        findConf path
+      else
+        findCabalDev Nothing
+findCabalDev Nothing = getCurrentDirectory >>= searchIt . splitPath
 
 addPath :: Options -> String -> Options
 addPath orig_opts path = do
     let orig_ghcopt = ghcOpts orig_opts
-    orig_opts { ghcOpts = orig_ghcopt ++ ["-package-conf", path] }
+    orig_opts { ghcOpts = orig_ghcopt ++ ["-package-conf", path, "-no-user-package-conf"] }
 
 searchIt :: [FilePath] -> IO FilePath
 searchIt [] = throwIO $ userError "Not found"
diff --git a/GHCMod.hs b/GHCMod.hs
index f2f5a06..1c84c05 100644
--- a/GHCMod.hs
+++ b/GHCMod.hs
@@ -57,6 +57,9 @@ argspec = [ Option "l" ["tolisp"]
           , Option "o" ["operators"]
             (NoArg (\opts -> opts { operators = True }))
             "print operators, too"
+          , Option "s" ["sandbox"]
+            (ReqArg (\s opts -> opts { sandbox = Just s }) "path")
+            "specify cabal-dev sandbox (default 'cabal-dev`)"
           ]
 
 parseArgs :: [OptDescr (Options -> Options)] -> [String] -> (Options, [String])
diff --git a/Types.hs b/Types.hs
index 0be01be..0fb53e2 100644
--- a/Types.hs
+++ b/Types.hs
@@ -10,6 +10,7 @@ data Options = Options {
   , ghcOpts      :: [String]
   , operators    :: Bool
   , expandSplice :: Bool
+  , sandbox      :: Maybe String
   }
 
 defaultOptions :: Options
@@ -19,6 +20,7 @@ defaultOptions = Options {
   , ghcOpts      = []
   , operators    = False
   , expandSplice = False
+  , sandbox      = Nothing
   }
 
 ----------------------------------------------------------------