diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # ChangeLog for githash
 
+## 0.1.3.1
+
+* Clean up some warnings (addresses [fpco/optparse-simple#11](https://github.com/fpco/optparse-simple/issues/11))
+
 ## 0.1.3.0
 
 * Catch exceptions thrown by `readCreateProcessWithExitCode` to deal
diff --git a/githash.cabal b/githash.cabal
--- a/githash.cabal
+++ b/githash.cabal
@@ -1,13 +1,13 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.30.0.
+-- This file has been generated from package.yaml by hpack version 0.31.1.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 2d1ac1215ae90e4ef0ec7e8b32fb6fae19439ce136c6f063598c703167993f92
+-- hash: e259226f20bb47090315089e5ac66234ed83b30d011b5f6dc29b4f74f8134b58
 
 name:           githash
-version:        0.1.3.0
+version:        0.1.3.1
 synopsis:       Compile git revision info into Haskell projects
 description:    Please see the README and documentation at <https://www.stackage.org/package/githash>
 category:       Development
diff --git a/src/GitHash.hs b/src/GitHash.hs
--- a/src/GitHash.hs
+++ b/src/GitHash.hs
@@ -20,12 +20,13 @@
 -- > panic :: String -> a
 -- > panic msg = error panicMsg
 -- >   where panicMsg =
--- >           concat [ "[panic ", $(gitBranch), "@", $(gitHash)
--- >                  , " (", $(gitCommitDate), ")"
--- >                  , " (", $(gitCommitCount), " commits in HEAD)"
+-- >           concat [ "[panic ", giBranch gi, "@", giHash gi
+-- >                  , " (", giCommitDate gi, ")"
+-- >                  , " (", show (giCommitCount gi), " commits in HEAD)"
 -- >                  , dirty, "] ", msg ]
--- >         dirty | $(gitDirty) = " (uncommitted files present)"
+-- >         dirty | giDirty gi = " (uncommitted files present)"
 -- >               | otherwise   = ""
+-- >         gi = $$tGitInfoCwd
 -- >
 -- > main = panic "oh no!"
 --
@@ -56,12 +57,9 @@
   , tGitInfoCwdTry
   ) where
 
-import Control.Applicative
 import Control.Exception
-import Control.Monad
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Char8 as B8
-import Data.Maybe
 import Data.Typeable (Typeable)
 import Language.Haskell.TH
 import Language.Haskell.TH.Syntax
@@ -181,6 +179,7 @@
 getGitRoot :: FilePath -> IO (Either GitHashException FilePath)
 getGitRoot dir = fmap (normalise . takeWhile (/= '\n')) `fmap` (runGit dir ["rev-parse", "--show-toplevel"])
 
+runGit :: FilePath -> [String] -> IO (Either GitHashException String)
 runGit root args = do
   let cp = (proc "git" args) { cwd = Just root }
   eres <- try $ readCreateProcessWithExitCode cp ""