diff --git a/projectroot.cabal b/projectroot.cabal
--- a/projectroot.cabal
+++ b/projectroot.cabal
@@ -1,10 +1,10 @@
 name:                projectroot
-version:             0.1.0.1
+version:             0.2.0.1
 synopsis:            Bindings to the projectroot C logic
 description: Simple way of finding the root of a project given an
              entry-point. This module provides bindings to the
              <https://github.com/yamadapc/projectroot projectroot> C library
-homepage:            https://gitlab.com/yamadapc/haskell-projectroot
+homepage:            https://github.com/yamadapc/haskell-projectroot
 license:             MIT
 license-file:        LICENSE
 author:              Pedro Tacla Yamada
@@ -13,7 +13,12 @@
 category:            System
 build-type:          Simple
 cabal-version:       >=1.10
+tested-with: GHC >= 7.6
 
+source-repository head
+  type:     git
+  location: git://github.com/yamadapc/haskell-projectroot
+
 library
   exposed-modules:     System.Directory.ProjectRoot
   build-depends:       base >=4 && <5
@@ -26,3 +31,13 @@
                      , ./projectroot/deps/commander/commander.h
   cc-options:          -std=c99
   include-dirs:        .
+
+test-suite hspec
+  main-is: Spec.hs
+  type: exitcode-stdio-1.0
+  build-depends: base
+               , hspec
+               , QuickCheck
+               , projectroot
+  hs-source-dirs: test
+  default-language: Haskell2010
diff --git a/src/System/Directory/ProjectRoot.hs b/src/System/Directory/ProjectRoot.hs
--- a/src/System/Directory/ProjectRoot.hs
+++ b/src/System/Directory/ProjectRoot.hs
@@ -12,31 +12,39 @@
 module System.Directory.ProjectRoot
   where
 
-import           Control.Monad    ((<=<), (>=>))
-import           Foreign.C
-import           System.Directory (getCurrentDirectory)
+import           Control.Applicative ((<$>))
+import           Foreign.C           (CString, newCString, peekCString)
+import           Foreign.Ptr         (nullPtr)
+import           System.Directory    (getCurrentDirectory)
 
 -- * Haskell Wrappers
 
 -- |
 -- Find the project root given an entry point
-getProjectRoot :: FilePath -> IO FilePath
-getProjectRoot = (find_project_root <=< newCString) >=> peekCString
+getProjectRoot :: FilePath -> IO (Maybe FilePath)
+getProjectRoot fp = do
+    root <- find_project_root =<< newCString fp
+    if root == nullPtr
+        then return Nothing
+        else Just <$> peekCString root
 
 -- |
 -- Find the weighted project root given an entry point
-getProjectRootWeighted :: FilePath -> IO FilePath
-getProjectRootWeighted = (find_project_root_weighted <=< newCString) >=>
-                         peekCString
+getProjectRootWeighted :: FilePath -> IO (Maybe FilePath)
+getProjectRootWeighted fp = do
+    root <- find_project_root_weighted =<< newCString fp
+    if root == nullPtr
+        then return Nothing
+        else Just <$> peekCString root
 
 -- |
 -- Find the project root of the current directory
-getProjectRootCurrent :: IO FilePath
+getProjectRootCurrent :: IO (Maybe FilePath)
 getProjectRootCurrent = getCurrentDirectory >>= getProjectRoot
 
 -- |
 -- Find the weighted project root of the current directory
-getProjectRootWeightedCurrent :: IO FilePath
+getProjectRootWeightedCurrent :: IO (Maybe FilePath)
 getProjectRootWeightedCurrent = getCurrentDirectory >>= getProjectRootWeighted
 
 -- * C functions
diff --git a/test/Spec.hs b/test/Spec.hs
new file mode 100644
--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,1 @@
+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}