diff --git a/cabal2nix.cabal b/cabal2nix.cabal
--- a/cabal2nix.cabal
+++ b/cabal2nix.cabal
@@ -3,7 +3,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           cabal2nix
-version:        2.2
+version:        2.2.1
 synopsis:       Convert Cabal files into Nix build instructions.
 description:    Convert Cabal files into Nix build instructions. Users of Nix can install the latest version by running:
                 .
diff --git a/cabal2nix/Main.hs b/cabal2nix/Main.hs
--- a/cabal2nix/Main.hs
+++ b/cabal2nix/Main.hs
@@ -114,7 +114,7 @@
 main = bracket (return ()) (\() -> hFlush stdout >> hFlush stderr) $ \() -> do
   Options {..} <- execParser pinfo
 
-  pkg <- getPackage optHackageDb $ Source optUrl (fromMaybe "" optRevision) (maybe UnknownHash Guess optSha256) (fromMaybe "." optSubpath)
+  pkg <- getPackage optHackageDb $ Source optUrl (fromMaybe "" optRevision) (maybe UnknownHash Guess optSha256) (fromMaybe "" optSubpath)
 
   let
       deriv :: Derivation
diff --git a/src/Distribution/Nixpkgs/Haskell/FromCabal.hs b/src/Distribution/Nixpkgs/Haskell/FromCabal.hs
--- a/src/Distribution/Nixpkgs/Haskell/FromCabal.hs
+++ b/src/Distribution/Nixpkgs/Haskell/FromCabal.hs
@@ -75,6 +75,7 @@
     & enableSplitObjs .~ True
     & enableLibraryProfiling .~ False
     & enableExecutableProfiling .~ False
+    & subpath .~ "."
     & phaseOverrides .~ mempty
     & editedCabalFile .~ (if xrev > 0
                              then fromMaybe (error (display package ++ ": X-Cabal-File-Hash field is missing")) (lookup "X-Cabal-File-Hash" customFieldsPD)