diff --git a/Main.hs b/Main.hs
--- a/Main.hs
+++ b/Main.hs
@@ -75,7 +75,6 @@
 import Control.Monad.Trans.Class        (lift)
 import Control.Monad.Trans.State.Strict (StateT)
 import Data.Aeson                       (FromJSON)
-import Data.Fix                         (Fix)
 import Data.List.NonEmpty               (NonEmpty (..))
 import Data.Text                        (Text)
 import Data.Void                        (Void)
@@ -188,6 +187,7 @@
         (   Options.long "file"
         <>  Options.help "File to import, relative to the top-level directory"
         <>  Options.value "package.dhall"
+        <>  Options.action "file"
         )
 
 parseSource :: Parser Bool
@@ -239,6 +239,7 @@
             (   Options.long "directory"
             <>  Options.help "Subdirectory containing the Dhall package"
             <>  Options.value ""
+            <>  Options.action "directory"
             )
 
     file <- parseFile
@@ -285,13 +286,6 @@
 nub :: Ord a => [a] -> [a]
 nub = Foldl.fold Foldl.nub
 
-{-| This specialization of `nub` is necessary to work around a type-checking
-    loop with GHC 8.4
--}
-nub'
-    :: Ord (f (Fix f)) => [ (Text, Maybe (Fix f)) ] -> [ (Text, Maybe (Fix f)) ]
-nub' = nub
-
 {-| The Nixpkgs support for Dhall essentially replaces all remote imports with
     cache hits, but doing so implies that all remote imports must be protected
     by an integrity check.
@@ -599,7 +593,7 @@
             Nix.mkFunction
                 (Nix.mkParamset
                     (   [ (buildDhallGitHubPackage, Nothing) ]
-                    <>  nub' (fmap functionParameter nixDependencies)
+                    <>  nub (fmap functionParameter nixDependencies)
                     )
                     False
                 )
@@ -660,7 +654,7 @@
             Nix.mkFunction
                 (Nix.mkParamset
                     (   [ (buildDhallDirectoryPackage, Nothing) ]
-                    <>  nub' (fmap functionParameter nixDependencies)
+                    <>  nub (fmap functionParameter nixDependencies)
                     )
                     False
                 )
diff --git a/dhall-nixpkgs.cabal b/dhall-nixpkgs.cabal
--- a/dhall-nixpkgs.cabal
+++ b/dhall-nixpkgs.cabal
@@ -1,6 +1,6 @@
+Version:             1.0.2
 Cabal-Version:       >=1.10
 Name:                dhall-nixpkgs
-Version:             1.0.1
 Synopsis:            Convert Dhall projects to Nix packages
 Description:         This package provides a @dhall-to-nixpkgs@ executable that
                      converts a Dhall project to a Nix expression that can be
@@ -19,9 +19,9 @@
   Build-Depends:       base                 >= 4.11     && < 5
                      , aeson                >= 1.0.0.0  && < 1.5
                      , data-fix
-                     , dhall                >= 1.32.0   && < 1.36
+                     , dhall                >= 1.32.0   && < 1.37
                      , foldl                               < 1.5
-                     , hnix                 >= 0.7      && < 0.10
+                     , hnix                 >= 0.10.1   && < 0.11
                      , lens-family-core     >= 1.0.0    && < 2.2
                      , megaparsec           >= 7.0.0    && < 9.1
                      , mmorph                              < 1.2