diff --git a/CHANGES.txt b/CHANGES.txt
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,5 +1,10 @@
 Changelog for HLint
 
+1.9.6
+    #85, fix the free variable matching check for lambda
+    #84, suggest fmap for Either
+    Make --json put each hint on a different line
+    Support -X for extensions to the hse mode
 1.9.5
     Remove support for GHC 7.2
     Upgrade to haskell-src-exts-1.16
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -18,6 +18,7 @@
 * The presence of `seq` may cause some hints (i.e. eta-reduction) to change the semantics of a program.
 * Either the monomorphism restriction, or rank-2 types, may cause transformed programs to require type signatures to be manually inserted.
 * The `RebindableSyntax` extension can cause HLint to suggest incorrect changes.
+* HLint turns on many language extensions so it can parse more documents, occasionally some break otherwise legal syntax - e.g. `{-#INLINE foo#-}` doesn't work with `MagicHash`. These extensions can be disabled with `-XNoMagicHash`.
 
 ## Installing and running HLint
 
diff --git a/data/Default.hs b/data/Default.hs
--- a/data/Default.hs
+++ b/data/Default.hs
@@ -216,7 +216,7 @@
 warn "Use uncurry" = (\(x,y) -> f x y) ==> uncurry f where note = IncreasesLaziness
 error "Redundant $" = (($) . f) ==> f
 error "Redundant $" = (f $) ==> f
-warn  = (\x -> y) ==> const y where _ = isAtom y && notIn x y
+warn  = (\x -> y) ==> const y where _ = isAtom y
 error "Redundant flip" = flip f x y ==> f y x where _ = isApp original
 warn  = (\a b -> g (f a) (f b)) ==> g `Data.Function.on` f
 error "Evaluate" = id x ==> x
@@ -396,6 +396,7 @@
 
 error = [a | Left a <- a] ==> lefts a
 error = [a | Right a <- a] ==> rights a
+error = either Left (Right . f) ==> fmap f
 
 -- INFIX
 
@@ -621,6 +622,13 @@
 bar = [x| (x,_) <- pts]
 return' x = x `seq` return x
 foo = last (sortBy (compare `on` fst) xs) -- maximumBy (compare `on` fst) xs
+g = \ f -> parseFile f >>= (\ cu -> return (f, cu))
+foo = bar $ \(x,y) -> x x y
+foo = (\x -> f x >>= g) -- f Control.Monad.>=> g
+foo = (\f -> h f >>= g) -- h Control.Monad.>=> g
+foo = (\f -> h f >>= f)
+foo = bar $ \x -> [x,y]
+foo = bar $ \x -> [z,y] -- const [z,y]
 
 import Prelude \
 yes = flip mapM -- Control.Monad.forM
diff --git a/hlint.cabal b/hlint.cabal
--- a/hlint.cabal
+++ b/hlint.cabal
@@ -1,7 +1,7 @@
 cabal-version:      >= 1.6
 build-type:         Simple
 name:               hlint
-version:            1.9.5
+version:            1.9.6
 license:            BSD3
 license-file:       LICENSE
 category:           Development
diff --git a/src/CmdLine.hs b/src/CmdLine.hs
--- a/src/CmdLine.hs
+++ b/src/CmdLine.hs
@@ -118,6 +118,7 @@
         }
     | CmdHSE
         {cmdFiles :: [FilePath]
+        ,cmdLanguage :: [String]      -- ^ the extensions (may be prefixed by "No")
         }
     deriving (Data,Typeable,Show)
 
diff --git a/src/HLint.hs b/src/HLint.hs
--- a/src/HLint.hs
+++ b/src/HLint.hs
@@ -57,11 +57,11 @@
         CmdTest{} -> hlintTest cmd >> return []
 
 hlintHSE :: Cmd -> IO ()
-hlintHSE CmdHSE{..} = do
+hlintHSE c@CmdHSE{..} = do
     v <- getVerbosity
     forM_ cmdFiles $ \x -> do
         putStrLn $ "Parse result of " ++ x ++ ":"
-        res <- parseFile x
+        res <- parseFileWithExts (cmdExtensions c) x
         case res of
             x@ParseFailed{} -> print x
             ParseOk m -> case v of
diff --git a/src/Hint/Match.hs b/src/Hint/Match.hs
--- a/src/Hint/Match.hs
+++ b/src/Hint/Match.hs
@@ -103,7 +103,9 @@
     u <- check u
     let e = subst u hintRuleRHS
     let res = addBracket parent $ unqualify hintRuleScope s u $ performEval e
-    guard $ (freeVars e Set.\\ freeVars hintRuleRHS) `Set.isSubsetOf` freeVars x -- check no unexpected new free variables
+    guard $ (freeVars e Set.\\ Set.filter (not . isUnifyVar) (freeVars hintRuleRHS))
+            `Set.isSubsetOf` freeVars x
+        -- check no unexpected new free variables
     guard $ checkSide hintRuleSide $ ("original",x) : ("result",res) : u
     guard $ checkDefine decl parent res
     return (res,hintRuleNotes)
diff --git a/src/Idea.hs b/src/Idea.hs
--- a/src/Idea.hs
+++ b/src/Idea.hs
@@ -43,7 +43,7 @@
     wrap x = "{" ++ x ++ "}"
 
 showIdeasJson :: [Idea] -> String
-showIdeasJson ideas = "[" ++ intercalate "," (map showIdeaJson ideas) ++ "]"
+showIdeasJson ideas = "[" ++ intercalate "\n," (map showIdeaJson ideas) ++ "]"
 
 instance Show Idea where
     show = showEx id