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:             0.1.0.0
+version:             0.1.0.1
 synopsis:            Protocol buffer compiler for the proto-lens library.
 description:
   Turn protocol buffer files (.proto) into Haskell files (.hs) which
@@ -18,16 +18,16 @@
   default-language:  Haskell2010
   hs-source-dirs:    src
   build-depends:
-        Cabal == 1.22.*
-      , base == 4.8.*
+        Cabal >= 1.22 && < 1.25
+      , base >= 4.8 && < 4.10
       , bytestring == 0.10.*
       , containers == 0.5.*
       , data-default-class == 0.0.*
       , directory == 1.2.*
       , filepath == 1.4.*
       , lens-family == 1.2.*
-      , process == 1.2.*
-      , proto-lens == 0.1.0.0
+      , process >= 1.2 && < 1.5
+      , proto-lens == 0.1.0.1
       , text == 1.2.*
   reexported-modules:
       -- Modules that are needed by the generated Haskell files:
@@ -50,7 +50,7 @@
       Generate
 
   build-depends:
-        base == 4.8.*
+        base >= 4.8 && < 4.10
       , bytestring == 0.10.*
       , containers == 0.5.*
       , data-default-class == 0.0.*
@@ -59,7 +59,7 @@
       , lens-family == 1.2.*
       -- Specify an exact version of `proto-lens`, since it's tied closely
       -- to the generated code.
-      , proto-lens == 0.1.0.0
+      , proto-lens == 0.1.0.1
       , text == 1.2.*
   hs-source-dirs:      src
   default-language:    Haskell2010
diff --git a/src/Data/ProtoLens/Setup.hs b/src/Data/ProtoLens/Setup.hs
--- a/src/Data/ProtoLens/Setup.hs
+++ b/src/Data/ProtoLens/Setup.hs
@@ -19,8 +19,17 @@
     , generateProtos
     ) where
 
-import Distribution.PackageDescription (extraSrcFiles)
+import Distribution.PackageDescription
+    ( PackageDescription(..)
+    , benchmarkBuildInfo
+    , buildInfo
+    , extraSrcFiles
+    , hsSourceDirs
+    , libBuildInfo
+    , testBuildInfo
+    )
 import Distribution.Simple.BuildPaths (autogenModulesDir)
+import Distribution.Simple.LocalBuildInfo (LocalBuildInfo)
 import Distribution.Simple.Program (knownPrograms, ConfiguredProgram(..))
 import Distribution.Simple.Program.Types (simpleProgram)
 import Distribution.Simple.Utils (matchFileGlob)
@@ -68,7 +77,11 @@
 generatingProtos root hooks = hooks
     { buildHook = \p l h f -> generateSources p l >> buildHook hooks p l h f
     , haddockHook = \p l h f -> generateSources p l >> haddockHook hooks p l h f
-    -- TODO: add a hook for sdist.
+    , sDistHook = \p maybe_l h f -> case maybe_l of
+            Nothing -> error "Can't run protoc; run 'cabal configure' first."
+            Just l -> do
+                        generateSources p l
+                        sDistHook hooks (fudgePackageDesc l p) maybe_l h f
     }
   where
     generateSources p l = do
@@ -78,6 +91,29 @@
             $ filter (isSubdirectoryOf root)
             $ filter (\f -> takeExtension f == ".proto")
                 files
+
+-- | Add the autogen directory to the hs-source-dirs of all the targets in the
+-- .cabal file.  Used to fool 'sdist' by pointing it to the generated source
+-- files.
+fudgePackageDesc :: LocalBuildInfo -> PackageDescription -> PackageDescription
+fudgePackageDesc lbi p = p
+    { library =
+        (\lib -> lib { libBuildInfo = fudgeBuildInfo (libBuildInfo lib) })
+            <$> library p
+    , executables =
+        (\exe -> exe { buildInfo = fudgeBuildInfo (buildInfo exe) })
+            <$> executables p
+    , testSuites =
+        (\test -> test { testBuildInfo = fudgeBuildInfo (testBuildInfo test) })
+            <$> testSuites p
+    , benchmarks =
+        (\bench -> bench { benchmarkBuildInfo =
+                              fudgeBuildInfo (benchmarkBuildInfo bench) })
+            <$> benchmarks p
+    }
+  where
+    fudgeBuildInfo bi =
+        bi { hsSourceDirs = autogenModulesDir lbi : hsSourceDirs bi }
 
 -- | Returns whether the @root@ is a parent folder of @f@.
 isSubdirectoryOf :: FilePath -> FilePath -> Bool
diff --git a/src/Definitions.hs b/src/Definitions.hs
--- a/src/Definitions.hs
+++ b/src/Definitions.hs
@@ -108,7 +108,9 @@
 -- nested in other messages), and assign Haskell names to them.
 collectDefinitions :: FileDescriptorProto -> Env Name
 collectDefinitions fd = let
-    protoPrefix = "." <> (fd ^. package) <> "."
+    protoPrefix = case fd ^. package of
+        "" -> "."
+        p -> "." <> p <> "."
     hsPrefix = ""
     in Map.fromList $ messageAndEnumDefs protoPrefix hsPrefix
                           (fd ^. messageType) (fd ^. enumType)