diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,11 @@
 
 # Revision history for nixfmt
 
+## 0.4.0 -- 2020-02-10
+* Report non-conforming files on the same line to aid line-oriented processing
+* Fix help, summary, and version flag contents.
+* Fix indentation of leading comments in parens
+
 ## 0.3.0 -- 2019-08-29
 
 * Added check flag for use in CI.
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -15,10 +15,16 @@
 
 ## Installation
 
-* Optional: `cachix use nixfmt`
-* `nix-env -f https://github.com/serokell/nixfmt/archive/master.tar.gz -i`
+- `nixfmt` is in nixpkgs master as of 2019-09-04: 
 
+      nix-env -iA nixpkgs.nixfmt
 
+- To get the most recent version, install from master:
+
+      # Optional: use cachix to get cached builds even for master
+      cachix use nixfmt
+      nix-env -f https://github.com/serokell/nixfmt/archive/master.tar.gz -i
+
 ## Development
 
 ### With Nix
@@ -30,7 +36,7 @@
 
 ### Without Nix
 
-Haskell dependencies will be bulit by Cabal.
+Haskell dependencies will be built by Cabal.
 
 * Build with `cabal new-build`
 
diff --git a/main/Main.hs b/main/Main.hs
--- a/main/Main.hs
+++ b/main/Main.hs
@@ -12,11 +12,13 @@
 import Data.Bifunctor (first)
 import Data.Either (lefts)
 import Data.Text (Text)
+import Data.Version (showVersion)
 import GHC.IO.Encoding (utf8)
+import Paths_nixfmt (version)
 import System.Console.CmdArgs
   (Data, Typeable, args, cmdArgs, help, summary, typ, (&=))
 import System.Exit (ExitCode(..), exitFailure, exitSuccess)
-import System.IO (hPutStr, hSetEncoding, stderr)
+import System.IO (hPutStrLn, hSetEncoding, stderr)
 import System.Posix.Process (exitImmediately)
 import System.Posix.Signals (Handler(..), installHandler, keyboardSignal)
 
@@ -42,7 +44,8 @@
     , width = 80 &= help "Maximum width in characters"
     , check = False &= help "Check whether files are formatted"
     , quiet = False &= help "Do not report errors"
-    } &= summary "Format Nix source code"
+    } &= summary ("nixfmt v" ++ showVersion version)
+    &= help "Format Nix source code"
 
 format' :: Width -> FilePath -> Text -> Either String Text
 format' w path = first errorBundlePretty . format w path
@@ -68,7 +71,7 @@
         Left err -> Left err
         Right formatted
             | formatted == contents -> Right ()
-            | otherwise             -> Left $ tPath ++ ":\nnot formatted"
+            | otherwise             -> Left $ tPath ++ ": not formatted"
 
 stdioTarget :: Target
 stdioTarget = Target TextIO.getContents "<stdin>" TextIO.putStr
@@ -89,7 +92,7 @@
 toOperation Nixfmt{ width = w } = formatTarget w
 
 toWriteError :: Nixfmt -> String -> IO ()
-toWriteError Nixfmt{ quiet = False } = hPutStr stderr
+toWriteError Nixfmt{ quiet = False } = hPutStrLn stderr
 toWriteError Nixfmt{ quiet = True } = const $ return ()
 
 toJobs :: Nixfmt -> [IO Result]
diff --git a/nixfmt.cabal b/nixfmt.cabal
--- a/nixfmt.cabal
+++ b/nixfmt.cabal
@@ -6,7 +6,7 @@
 -- SPDX-License-Identifier: MPL-2.0
 
 name:                nixfmt
-version:             0.3.0
+version:             0.4.0
 synopsis:            An opinionated formatter for Nix
 description:
   A formatter for Nix that ensures consistent and clear formatting by forgetting
@@ -29,8 +29,11 @@
 executable nixfmt
   main-is:             Main.hs
   other-modules:
+    Paths_nixfmt
     System.IO.Utf8
     System.IO.Atomic
+  autogen-modules:
+    Paths_nixfmt
   other-extensions:    DeriveDataTypeable
   hs-source-dirs:      main
   if impl(ghcjs)
diff --git a/src/Nixfmt/Pretty.hs b/src/Nixfmt/Pretty.hs
--- a/src/Nixfmt/Pretty.hs
+++ b/src/Nixfmt/Pretty.hs
@@ -111,8 +111,9 @@
         <> nest 2 (pretty leading <> sepBy hardline binders) <> line
         <> pretty parclose
 
-prettyTerm (Parenthesized paropen expr parclose)
-    = base $ pretty paropen <> nest 2 (group expr) <> pretty parclose
+prettyTerm (Parenthesized (Ann paropen trailing leading) expr parclose)
+    = base $ pretty paropen <> pretty trailing
+        <> nest 2 (pretty leading <> group expr) <> pretty parclose
 
 instance Pretty Term where
     pretty l@(List _ _ _) = group $ prettyTerm l