diff --git a/proto-lens-protoc.cabal b/proto-lens-protoc.cabal
--- a/proto-lens-protoc.cabal
+++ b/proto-lens-protoc.cabal
@@ -1,5 +1,5 @@
 name:                proto-lens-protoc
-version:             0.2.0.0
+version:             0.2.0.1
 synopsis:            Protocol buffer compiler for the proto-lens library.
 description:
   Turn protocol buffer files (.proto) into Haskell files (.hs) which
@@ -47,8 +47,8 @@
         , lens-family == 1.2.*
         , lens-labels == 0.1.*
         , process >= 1.2 && < 1.5
-        , proto-lens == 0.2.0.0
-        , proto-lens-descriptors == 0.2.0.0
+        , proto-lens == 0.2.0.1
+        , proto-lens-descriptors == 0.2.0.1
         , text == 1.2.*
     reexported-modules:
         -- Modules that are needed by the generated Haskell files.
@@ -79,8 +79,8 @@
       , lens-family == 1.2.*
       -- Specify an exact version of `proto-lens`, since it's tied closely
       -- to the generated code.
-      , proto-lens == 0.2.0.0
-      , proto-lens-descriptors == 0.2.0.0
+      , proto-lens == 0.2.0.1
+      , proto-lens-descriptors == 0.2.0.1
       , text == 1.2.*
   hs-source-dirs:      src
   other-modules:
diff --git a/src/Data/ProtoLens/Compiler/Generate.hs b/src/Data/ProtoLens/Compiler/Generate.hs
--- a/src/Data/ProtoLens/Compiler/Generate.hs
+++ b/src/Data/ProtoLens/Compiler/Generate.hs
@@ -15,7 +15,6 @@
     ) where
 
 
-import Control.Applicative ((<$>))
 import Control.Arrow (second)
 import qualified Data.Foldable as F
 import qualified Data.List as List
@@ -34,7 +33,6 @@
     , FieldDescriptorProto'Label(..)
     , FieldDescriptorProto'Type(..)
     , FileDescriptorProto
-    , FieldOptions
     , defaultValue
     , label
     , mapEntry
@@ -321,14 +319,12 @@
 generateFieldDecls :: String -> [Decl]
 generateFieldDecls xStr =
     -- foo :: forall x f s t a b
-    --        . (Functor f, HasLens x f s t a b)
-    --        => LensLike f s t a b
+    --        . HasLens x f s t a b => LensLike f s t a b
+    -- -- Note: `Lens.Family2.LensLike f` implies Functor f.
     -- foo = lensOf (Proxy# :: Proxy# x)
     [ typeSig [x]
-          $ tyForAll ["x", "f", "s", "t", "a", "b"]
-                  [ classA "Prelude.Functor" ["f"]
-                  , classA "Lens.Labels.HasLens" [xSym, "f", "s", "t", "a", "b"]
-                  ]
+          $ tyForAll ["f", "s", "t", "a", "b"]
+                  [classA "Lens.Labels.HasLens" [xSym, "f", "s", "t", "a", "b"]]
                     $ "Lens.Family2.LensLike" @@ "f" @@ "s" @@ "t" @@ "a" @@ "b"
     , funBind [match x []
                   $ "Lens.Labels.lensOf"
diff --git a/src/protoc-gen-haskell.hs b/src/protoc-gen-haskell.hs
--- a/src/protoc-gen-haskell.hs
+++ b/src/protoc-gen-haskell.hs
@@ -9,10 +9,7 @@
 module Main where
 
 import qualified Data.ByteString as B
-import Data.Char (toUpper)
-import Data.List (foldl', intercalate)
-import qualified Data.Map.Strict as Map
-import Data.Map.Strict (Map, unions, (!))
+import Data.Map.Strict ((!))
 import Data.Monoid ((<>))
 import qualified Data.Set as Set
 import qualified Data.Text as T
@@ -29,27 +26,19 @@
     , protoFile
     )
 import Proto.Google.Protobuf.Descriptor
-    (FileDescriptorProto, name, dependency, publicDependency)
+    (FileDescriptorProto, name, dependency)
 import System.Environment (getProgName)
 import System.Exit (exitWith, ExitCode(..))
 import System.IO as IO
-import System.FilePath (dropExtension, replaceExtension, splitDirectories)
-import Text.Read (readEither)
 
-import Data.ProtoLens.Compiler.Combinators
-    ( ModuleName
-    , Name
-    , QName
-    , prettyPrint)
-import Data.ProtoLens.Compiler.Definitions
+import Data.ProtoLens.Compiler.Combinators (prettyPrint)
 import Data.ProtoLens.Compiler.Generate
 import Data.ProtoLens.Compiler.Plugin
-import System.Environment (getArgs)
 
+main :: IO ()
 main = do
     contents <- B.getContents
     progName <- getProgName
-    args <- getArgs
     case decodeMessage contents of
         Left e -> IO.hPutStrLn stderr e >> exitWith (ExitFailure 1)
         Right x -> B.putStr $ encodeMessage $ makeResponse progName x
@@ -79,22 +68,22 @@
   modulePrefix = "Proto"
   filesByName = analyzeProtoFiles modulePrefix files
   -- The contents of the generated Haskell file for a given .proto file.
-  buildFile file = let
-      deps = descriptor file ^. dependency
+  buildFile f = let
+      deps = descriptor f ^. dependency
       imports = Set.toAscList $ Set.fromList
                   [ haskellModule (filesByName ! exportName)
                   | dep <- deps
                   , exportName <- exports (filesByName ! dep)
                   ]
-      in generateModule (haskellModule file) imports
-             (fileSyntaxType (descriptor file))
+      in generateModule (haskellModule f) imports
+             (fileSyntaxType (descriptor f))
              modifyImports
-             (definitions file)
+             (definitions f)
              (collectEnvFromDeps deps filesByName)
-  in [ ( outputFilePath . prettyPrint . haskellModule $ file
-       , header (descriptor file) <> pack (prettyPrint $ buildFile file)
+  in [ ( outputFilePath . prettyPrint . haskellModule $ f
+       , header (descriptor f) <> pack (prettyPrint $ buildFile f)
        )
      | fileName <- toGenerate
-     , let file = filesByName ! fileName
+     , let f = filesByName ! fileName
      ]