diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,11 @@
+1.6.1.
+
+* BUG FIX: Fix `turtle` to build on Windows
+* BUG FIX: `stripPrefix` and `commonPrefix` now correctly handle files with
+  extensions
+  * For example, before this fix `stripPrefix "./" "./foo.bar"` would
+    return `Just "foo/.bar"`
+
 1.6.0
 
 * BREAKING CHANGE: Switch to the `FilePath` type from `base` instead of
diff --git a/src/Turtle/Internal.hs b/src/Turtle/Internal.hs
--- a/src/Turtle/Internal.hs
+++ b/src/Turtle/Internal.hs
@@ -51,12 +51,16 @@
 commonPrefix [ ] = mempty
 commonPrefix (path : paths) = foldr longestPathPrefix path paths
   where
-    longestPathPrefix left right =
-        FilePath.joinPath (longestPrefix leftComponents rightComponents)
+    longestPathPrefix left right
+        | leftComponents == rightComponents =
+               FilePath.joinPath leftComponents
+            ++ mconcat (longestPrefix leftExtensions rightExtensions)
+        | otherwise =
+           FilePath.joinPath (longestPrefix leftComponents rightComponents)
       where
-        leftComponents = splitExt (splitDirectories left)
+        (leftComponents, leftExtensions)  = splitExt (splitDirectories left)
 
-        rightComponents = splitExt (splitDirectories right)
+        (rightComponents, rightExtensions) = splitExt (splitDirectories right)
 
 longestPrefix :: Eq a => [a] -> [a] -> [a]
 longestPrefix (l : ls) (r : rs)
@@ -66,23 +70,30 @@
 -- | Remove a prefix from a path
 stripPrefix :: FilePath -> FilePath -> Maybe FilePath
 stripPrefix prefix path = do
-    suffix <- List.stripPrefix prefixComponents pathComponents
+    componentSuffix <- List.stripPrefix prefixComponents pathComponents
 
-    return (FilePath.joinPath suffix)
+    if null componentSuffix
+        then do
+            prefixSuffix <- List.stripPrefix prefixExtensions pathExtensions
+
+            return (mconcat prefixSuffix)
+        else do
+            return (FilePath.joinPath componentSuffix ++ mconcat pathExtensions)
   where
-    prefixComponents = splitExt (splitDirectories prefix)
+    (prefixComponents, prefixExtensions) = splitExt (splitDirectories prefix)
 
-    pathComponents = splitExt (splitDirectories path)
+    (pathComponents, pathExtensions) = splitExt (splitDirectories path)
 
 -- Internal helper function for `stripPrefix` and `commonPrefix`
-splitExt :: [FilePath] -> [FilePath]
-splitExt [ component ] = base : map ("." ++) exts
+splitExt :: [FilePath] -> ([FilePath], [String])
+splitExt [ component ] = ([ base ], map ("." ++) exts)
   where
     (base, exts) = splitExtensions component
 splitExt [ ] =
-    [ ]
-splitExt (component : components) =
-    component : splitExt components
+    ([ ], [ ])
+splitExt (component : components) = (component : base, exts)
+  where
+    (base, exts) = splitExt components
 
 -- | Normalise a path
 collapse :: FilePath -> FilePath
diff --git a/src/Turtle/Prelude.hs b/src/Turtle/Prelude.hs
--- a/src/Turtle/Prelude.hs
+++ b/src/Turtle/Prelude.hs
@@ -982,13 +982,12 @@
     reparse <- fmap reparsePoint (Win32.getFileAttributes path')
     if (canRead && not reparse)
         then bracket
-            (Win32.findFirstFile (Filesystem.encodeString (path </> "*")))
+            (Win32.findFirstFile (path </> "*"))
             (\(h, _) -> Win32.findClose h)
             (\(h, fdat) -> do
                 let loop x = do
-                        file' <- Win32.getFindDataFileName fdat
-                        let file = Filesystem.decodeString file'
-                        x' <- if (file' /= "." && file' /= "..")
+                        file <- Win32.getFindDataFileName fdat
+                        x' <- if (file /= "." && file /= "..")
                             then step x (path </> file)
                             else return x
                         more <- Win32.findNextFile h fdat
@@ -1131,7 +1130,7 @@
     -- a directory and fails to strip it as a prefix from `/tmp/foo`.  Adding
     -- `(</> "")` to the end of the path makes clear that the path is a
     -- directory
-    Just suffix <- return (Internal.stripPrefix (oldTree ++ "/") oldPath)
+    Just suffix <- return (Internal.stripPrefix (oldTree <> [ FilePath.pathSeparator ]) oldPath)
 
     let newPath = newTree </> suffix
 
@@ -1221,7 +1220,7 @@
 #ifdef mingw32_HOST_OS
         then do
             handle <- Win32.createFile
-                (Filesystem.encodeString file)
+                file
                 Win32.gENERIC_WRITE
                 Win32.fILE_SHARE_NONE
                 Nothing
diff --git a/test/system-filepath.hs b/test/system-filepath.hs
--- a/test/system-filepath.hs
+++ b/test/system-filepath.hs
@@ -27,9 +27,14 @@
 test_Root :: TestTree
 test_Root = testCase "root" $ do
     "" @=? root ""
+#if defined(mingw32_HOST_OS) || defined(__MINGW32__)
+    "c:\\" @=? root "c:\\"
+    "c:\\" @=? root "c:\\foo"
+#else
     "/" @=? root "/"
-    "" @=? root "foo"
     "/" @=? root "/foo"
+#endif
+    "" @=? root "foo"
 
 test_Directory :: TestTree
 test_Directory = testCase "directory" $ do
@@ -59,7 +64,11 @@
     "../" @=? parent "../.."
     "../" @=? parent "../."
 
+#if defined(mingw32_HOST_OS) || defined(__MINGW32__)
+    "c:\\" @=? parent "c:\\"
+#else
     "/" @=? parent "/"
+#endif
     "./" @=? parent "foo"
     "./" @=? parent "./foo"
     "./foo/" @=? parent "foo/bar"
@@ -138,7 +147,6 @@
     myAssert' "c:\\foo\\bar"
     myAssert ""
     myAssert "foo\\bar"
-    myAssert' "\\foo\\bar"
 #else
     myAssert' "/"
     myAssert' "/foo/bar"
@@ -152,6 +160,7 @@
     "./" @=? commonPrefix [".", "."]
     "" @=? commonPrefix [".", ".."]
     "foo/" @=? commonPrefix ["foo/bar", "foo/baz"]
+    "foo/a.b" @=? commonPrefix ["foo/a.b.c", "foo/a.b.d"]
     "" @=? commonPrefix ["foo/", "bar/"]
 
 test_StripPrefix :: TestTree
@@ -160,6 +169,8 @@
     Just "/" @=? stripPrefix "" "/"
     Just "" @=? stripPrefix "/" "/"
     Just "foo" @=? stripPrefix "/" "/foo"
+    Just "foo" @=? stripPrefix "./" "./foo"
+    Just "foo.ext" @=? stripPrefix "./" "./foo.ext"
     Just "foo/bar" @=? stripPrefix "/" "/foo/bar"
     Just "bar" @=? stripPrefix "/foo/" "/foo/bar"
     Just "bar/baz" @=? stripPrefix "/foo/" "/foo/bar/baz"
@@ -176,10 +187,15 @@
 test_Collapse = testCase "collapse" $ do
     -- This behavior differs from the old `system-filepath` package, but this
     -- behavior is more correct in the presence of symlinks
+#if defined(mingw32_HOST_OS) || defined(__MINGW32__)
+    "foo\\..\\bar" @=? collapse "foo/../bar"
+    "foo\\bar" @=? collapse "foo/bar"
+    "foo\\bar" @=? collapse "foo/./bar"
+#else
     "foo/../bar" @=? collapse "foo/../bar"
-
     "foo/bar" @=? collapse "foo/bar"
     "foo/bar" @=? collapse "foo/./bar"
+#endif
 
 test_SplitDirectories :: TestTree
 test_SplitDirectories = testCase "splitDirectories" $ do
diff --git a/turtle.cabal b/turtle.cabal
--- a/turtle.cabal
+++ b/turtle.cabal
@@ -1,5 +1,5 @@
 Name: turtle
-Version: 1.6.0
+Version: 1.6.1
 Cabal-Version: >=1.10
 Build-Type: Simple
 License: BSD3