diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -4,7 +4,7 @@
 
 ## Finding Issues to Work On
 
-If you would like to contribute, please consider the issues in the current milestone first. If you are a new contributor, you may want to have a go at the ["easy" issues](https://github.com/purescript/purescript/labels/easy) to get started.
+If you would like to contribute, please consider the issues in the current milestone first. If you are a new contributor, you may want to have a go at the ["new contributor" issues](https://github.com/purescript/purescript/labels/new%20contributor) to get started.
 
 ## Pull Requests
 
diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -31,6 +31,7 @@
 | [@bsermons](https://github.com/bsermons) | Brian Sermons | [MIT license](http://opensource.org/licenses/MIT) |
 | [@cdepillabout](https://github.com/cdepillabout) | Dennis Gosnell | [MIT license](http://opensource.org/licenses/MIT) |
 | [@chrisdone](https://github.com/chrisdone) | Chris Done | MIT license |
+| [@cmdv](https://github.com/cmdv) | Vincent Orr | MIT license |
 | [@codedmart](https://github.com/codedmart) | Brandon Martin | [MIT license](http://opensource.org/licenses/MIT) |
 | [@davidchambers](https://github.com/davidchambers) | David Chambers | [MIT license](http://opensource.org/licenses/MIT) |
 | [@DavidLindbom](https://github.com/DavidLindbom) | David Lindbom | [MIT license](http://opensource.org/licenses/MIT) |
@@ -87,12 +88,14 @@
 | [@sebastiaanvisser](https://github.com/sebastiaanvisser) | Sebastiaan Visser | MIT license |
 | [@senju](https://github.com/senju) | senju | [MIT license](http://opensource.org/licenses/MIT) |
 | [@seungha-kim](https://github.com/seungha-kim) | Seungha Kim | [MIT license](http://opensource.org/licenses/MIT) |
+| [@simonyangme](https://github.com/simonyangme) | Simon Yang | [MIT license](http://opensource.org/licenses/MIT) |
 | [@sharkdp](https://github.com/sharkdp) | David Peter | [MIT license](http://opensource.org/licenses/MIT) |
 | [@soupi](https://github.com/soupi) | Gil Mizrahi | [MIT license](http://opensource.org/licenses/MIT) |
 | [@sztupi](https://github.com/sztupi) | Attila Sztupak | [MIT license](http://opensource.org/licenses/MIT) |
 | [@taktoa](https://github.com/taktoa) | Remy Goldschmidt | [MIT license](http://opensource.org/licenses/MIT) |
 | [@taku0](https://github.com/taku0) | taku0 | [MIT license](http://opensource.org/licenses/MIT) |
 | [@tfausak](https://github.com/tfausak) | Taylor Fausak | [MIT license](http://opensource.org/licenses/MIT) |
+| [@thoradam](https://github.com/thoradam) | Thor Adam | [MIT license](http://opensource.org/licenses/MIT) |
 | [@tmcgilchrist](https://github.com/tmcgilchrist) | Tim McGilchrist | [MIT license](http://opensource.org/licenses/MIT) |
 | [@trofi](https://github.com/trofi) | Sergei Trofimovich | [MIT license](http://opensource.org/licenses/MIT) |
 | [@utkarshkukreti](https://github.com/utkarshkukreti) | Utkarsh Kukreti | [MIT license](http://opensource.org/licenses/MIT) |
diff --git a/app/Command/Ide.hs b/app/Command/Ide.hs
--- a/app/Command/Ide.hs
+++ b/app/Command/Ide.hs
@@ -80,10 +80,10 @@
   subcommands :: Opts.Parser (IO ())
   subcommands = (Opts.subparser . fold)
     [ Opts.command "server"
-        (Opts.info (fmap server serverOptions)
+        (Opts.info (fmap server serverOptions <**> Opts.helper)
           (Opts.progDesc "Start a server process"))
     , Opts.command "client"
-        (Opts.info (fmap client clientOptions)
+        (Opts.info (fmap client clientOptions <**> Opts.helper)
           (Opts.progDesc "Connect to a running server"))
     ]
 
@@ -119,7 +119,7 @@
       putText "psc-ide needs you to compile your project (for example by running pulp build)"
 
     unless noWatch $
-      void (forkFinally (watcher polling ideState fullOutputPath) print)
+      void (forkFinally (watcher polling logLevel ideState fullOutputPath) print)
     let conf = Configuration {confLogLevel = logLevel, confOutputPath = outputPath, confGlobs = globs}
         env = IdeEnvironment {ideStateVar = ideState, ideConfiguration = conf}
     startServer port env
diff --git a/app/Command/REPL.hs b/app/Command/REPL.hs
--- a/app/Command/REPL.hs
+++ b/app/Command/REPL.hs
@@ -62,7 +62,7 @@
 
 inputFile :: Opts.Parser FilePath
 inputFile = Opts.strArgument $
-     Opts.metavar "FILE"
+     Opts.metavar "FILES"
   <> Opts.help "Optional .purs files to load on start"
 
 nodePathOption :: Opts.Parser (Maybe FilePath)
diff --git a/app/Main.hs b/app/Main.hs
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -17,6 +17,7 @@
 import           Data.Foldable (fold)
 import           Data.Monoid ((<>))
 import qualified Options.Applicative as Opts
+import           System.Environment (getArgs)
 import qualified System.IO as IO
 import           Version (versionString)
 
@@ -25,13 +26,19 @@
 main = do
     IO.hSetEncoding IO.stdout IO.utf8
     IO.hSetEncoding IO.stderr IO.utf8
-    cmd <- Opts.execParser opts
+    cmd <- Opts.handleParseResult . execParserPure opts =<< getArgs
     cmd
   where
     opts        = Opts.info (versionInfo <*> Opts.helper <*> commands) infoModList
     infoModList = Opts.fullDesc <> headerInfo <> footerInfo
     headerInfo  = Opts.progDesc "The PureScript compiler and tools"
     footerInfo  = Opts.footer $ "purs " ++ versionString
+
+    -- | Displays full command help when invoked with no arguments.
+    execParserPure :: Opts.ParserInfo a -> [String] -> Opts.ParserResult a
+    execParserPure pinfo [] = Opts.Failure $
+      Opts.parserFailure Opts.defaultPrefs pinfo Opts.ShowHelpText mempty
+    execParserPure pinfo args = Opts.execParserPure Opts.defaultPrefs pinfo args
 
     versionInfo :: Opts.Parser (a -> a)
     versionInfo = Opts.abortOption (Opts.InfoMsg versionString) $
diff --git a/examples/docs/src/TypeLevelString.purs b/examples/docs/src/TypeLevelString.purs
new file mode 100644
--- /dev/null
+++ b/examples/docs/src/TypeLevelString.purs
@@ -0,0 +1,7 @@
+module TypeLevelString where
+
+data Foo
+
+class Bar a
+
+instance fooBar :: Fail "oops" => Bar Foo
diff --git a/examples/warning/CustomWarning2.purs b/examples/warning/CustomWarning2.purs
new file mode 100644
--- /dev/null
+++ b/examples/warning/CustomWarning2.purs
@@ -0,0 +1,11 @@
+-- @shouldWarnWith UserDefinedWarning
+module Main where
+
+foo :: Warn "foo" => Int -> Int
+foo x = x
+
+bar :: Warn "foo" => Int
+bar = foo 42
+
+baz :: Int
+baz = bar
diff --git a/examples/warning/CustomWarning3.purs b/examples/warning/CustomWarning3.purs
new file mode 100644
--- /dev/null
+++ b/examples/warning/CustomWarning3.purs
@@ -0,0 +1,13 @@
+-- @shouldWarnWith UserDefinedWarning
+-- @shouldWarnWith UserDefinedWarning
+module Main where
+
+foo :: Warn "foo" => Int -> Int
+foo x = x
+
+-- Defer the "foo" warning and warn with "bar" as well
+bar :: Warn "foo" => Warn "bar" => Int
+bar = foo 42
+
+baz :: Int
+baz = bar
diff --git a/purescript.cabal b/purescript.cabal
--- a/purescript.cabal
+++ b/purescript.cabal
@@ -1,9 +1,9 @@
--- This file has been generated from package.yaml by hpack version 0.15.0.
+-- This file has been generated from package.yaml by hpack version 0.17.0.
 --
 -- see: https://github.com/sol/hpack
 
 name:           purescript
-version:        0.11.3
+version:        0.11.4
 cabal-version:  >= 1.10
 build-type:     Simple
 license:        BSD3
@@ -59,6 +59,7 @@
       examples/docs/src/TypeClassWithFunDeps.purs
       examples/docs/src/TypeClassWithoutMembers.purs
       examples/docs/src/TypeClassWithoutMembersIntermediate.purs
+      examples/docs/src/TypeLevelString.purs
       examples/docs/src/TypeOpAliases.purs
       examples/docs/src/UTF8.purs
       examples/docs/src/Virtual.purs
@@ -585,6 +586,8 @@
       examples/warning/2411.purs
       examples/warning/2542.purs
       examples/warning/CustomWarning.purs
+      examples/warning/CustomWarning2.purs
+      examples/warning/CustomWarning3.purs
       examples/warning/DuplicateExportRef.purs
       examples/warning/DuplicateImport.purs
       examples/warning/DuplicateImportRef.purs
@@ -645,7 +648,7 @@
 
 library
     build-depends:
-          aeson >=0.8 && <1.1
+          aeson >=1.0 && <1.1
         , aeson-better-errors >=0.8
         , ansi-terminal >=0.6.2 && <0.7
         , base >=4.8 && <5
@@ -853,7 +856,7 @@
 
 executable purs
     build-depends:
-          aeson >=0.8 && <1.1
+          aeson >=1.0 && <1.1
         , aeson-better-errors >=0.8
         , ansi-terminal >=0.6.2 && <0.7
         , base >=4.8 && <5
@@ -941,7 +944,7 @@
 
 test-suite tests
     build-depends:
-          aeson >=0.8 && <1.1
+          aeson >=1.0 && <1.1
         , aeson-better-errors >=0.8
         , ansi-terminal >=0.6.2 && <0.7
         , base >=4.8 && <5
diff --git a/src/Language/PureScript/AST/Operators.hs b/src/Language/PureScript/AST/Operators.hs
--- a/src/Language/PureScript/AST/Operators.hs
+++ b/src/Language/PureScript/AST/Operators.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DeriveGeneric #-}
 -- |
 -- Operators fixity and associativity
 --
@@ -5,6 +6,8 @@
 
 import Prelude.Compat
 
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Data.Aeson ((.=))
 import qualified Data.Aeson as A
 
@@ -19,8 +22,10 @@
 -- Associativity for infix operators
 --
 data Associativity = Infixl | Infixr | Infix
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData Associativity
+
 showAssoc :: Associativity -> String
 showAssoc Infixl = "infixl"
 showAssoc Infixr = "infixr"
@@ -42,7 +47,9 @@
 -- Fixity data for infix operators
 --
 data Fixity = Fixity Associativity Precedence
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
+
+instance NFData Fixity
 
 instance A.ToJSON Fixity where
   toJSON (Fixity associativity precedence) =
diff --git a/src/Language/PureScript/AST/SourcePos.hs b/src/Language/PureScript/AST/SourcePos.hs
--- a/src/Language/PureScript/AST/SourcePos.hs
+++ b/src/Language/PureScript/AST/SourcePos.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DeriveGeneric #-}
 -- |
 -- Source position information
 --
@@ -5,6 +6,8 @@
 
 import Prelude.Compat
 
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Data.Aeson ((.=), (.:))
 import qualified Data.Aeson as A
 import Data.Monoid
@@ -23,8 +26,10 @@
     -- Column number
     --
   , sourcePosColumn :: Int
-  } deriving (Show, Eq, Ord)
+  } deriving (Show, Eq, Ord, Generic)
 
+instance NFData SourcePos
+
 displaySourcePos :: SourcePos -> Text
 displaySourcePos sp =
   "line " <> T.pack (show (sourcePosLine sp)) <>
@@ -51,7 +56,9 @@
     -- End of the span
     --
   , spanEnd :: SourcePos
-  } deriving (Show, Eq, Ord)
+  } deriving (Show, Eq, Ord, Generic)
+
+instance NFData SourceSpan
 
 displayStartEndPos :: SourceSpan -> Text
 displayStartEndPos sp =
diff --git a/src/Language/PureScript/CoreImp/Optimizer/TCO.hs b/src/Language/PureScript/CoreImp/Optimizer/TCO.hs
--- a/src/Language/PureScript/CoreImp/Optimizer/TCO.hs
+++ b/src/Language/PureScript/CoreImp/Optimizer/TCO.hs
@@ -7,6 +7,7 @@
 import Data.Monoid ((<>))
 import Language.PureScript.CoreImp.AST
 import Language.PureScript.AST.SourcePos (SourceSpan)
+import Safe (headDef, tailSafe)
 
 -- | Eliminate tail calls
 tco :: AST -> AST
@@ -29,10 +30,11 @@
   convert :: AST -> AST
   convert (VariableIntroduction ss name (Just fn@Function {}))
       | isTailRecursive name body'
-      = VariableIntroduction ss name (Just (replace (toLoop name allArgs body')))
+      = VariableIntroduction ss name (Just (replace (toLoop name outerArgs innerArgs body')))
     where
+      innerArgs = headDef [] argss
+      outerArgs = concat . reverse $ tailSafe argss
       (argss, body', replace) = collectAllFunctionArgs [] id fn
-      allArgs = concat $ reverse argss
   convert js = js
 
   collectAllFunctionArgs :: [[Text]] -> (AST -> AST) -> AST -> ([[Text]], AST, AST -> AST)
@@ -79,21 +81,16 @@
     allInTailPosition _
       = False
 
-  toLoop :: Text -> [Text] -> AST -> AST
-  toLoop ident allArgs js =
+  toLoop :: Text -> [Text] -> [Text] -> AST -> AST
+  toLoop ident outerArgs innerArgs js =
       Block rootSS $
-        map (\arg -> VariableIntroduction rootSS arg (Just (Var rootSS (copyVar arg)))) allArgs ++
+        map (\arg -> VariableIntroduction rootSS (tcoVar arg) (Just (Var rootSS (copyVar arg)))) outerArgs ++
         [ VariableIntroduction rootSS tcoDone (Just (BooleanLiteral rootSS False))
         , VariableIntroduction rootSS tcoResult Nothing
-        ] ++
-        map (\arg ->
-          VariableIntroduction rootSS (tcoVar arg) Nothing) allArgs ++
-        [ Function rootSS (Just tcoLoop) allArgs (Block rootSS [loopify js])
+        , Function rootSS (Just tcoLoop) (outerArgs ++ innerArgs) (Block rootSS [loopify js])
         , While rootSS (Unary rootSS Not (Var rootSS tcoDone))
             (Block rootSS
-              (Assignment rootSS (Var rootSS tcoResult) (App rootSS (Var rootSS tcoLoop) (map (Var rootSS) allArgs))
-              : map (\arg ->
-                  Assignment rootSS (Var rootSS arg) (Var rootSS (tcoVar arg))) allArgs))
+              [(Assignment rootSS (Var rootSS tcoResult) (App rootSS (Var rootSS tcoLoop) ((map (Var rootSS . tcoVar) outerArgs) ++ (map (Var rootSS . copyVar) innerArgs))))])
         , Return rootSS (Var rootSS tcoResult)
         ]
     where
@@ -107,7 +104,9 @@
         in
           Block ss $
             zipWith (\val arg ->
-              Assignment ss (Var ss (tcoVar arg)) val) allArgumentValues allArgs
+              Assignment ss (Var ss (tcoVar arg)) val) allArgumentValues outerArgs
+            ++ zipWith (\val arg ->
+              Assignment ss (Var ss (copyVar arg)) val) (drop (length outerArgs) allArgumentValues) innerArgs
             ++ [ ReturnNoResult ss ]
       | otherwise = Block ss [ markDone ss, Return ss ret ]
     loopify (ReturnNoResult ss) = Block ss [ markDone ss, ReturnNoResult ss ]
diff --git a/src/Language/PureScript/Docs/RenderedCode/RenderType.hs b/src/Language/PureScript/Docs/RenderedCode/RenderType.hs
--- a/src/Language/PureScript/Docs/RenderedCode/RenderType.hs
+++ b/src/Language/PureScript/Docs/RenderedCode/RenderType.hs
@@ -26,6 +26,7 @@
 import Language.PureScript.Pretty.Types
 import Language.PureScript.Types
 import Language.PureScript.Label (Label)
+import Language.PureScript.PSString (prettyPrintString)
 
 import Language.PureScript.Docs.RenderedCode.Types
 import Language.PureScript.Docs.Utils.MonoidExtras
@@ -54,6 +55,8 @@
     Just $ renderTypeAtom l <> sp <> renderTypeAtom op <> sp <> renderTypeAtom r
   match (TypeOp n) =
     Just (typeOp n)
+  match (TypeLevelString str) =
+    Just (syntax (prettyPrintString str))
   match _ =
     Nothing
 
diff --git a/src/Language/PureScript/Docs/Types.hs b/src/Language/PureScript/Docs/Types.hs
--- a/src/Language/PureScript/Docs/Types.hs
+++ b/src/Language/PureScript/Docs/Types.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE DeriveGeneric #-}
+
 module Language.PureScript.Docs.Types
   ( module Language.PureScript.Docs.Types
   , module ReExports
@@ -7,6 +9,8 @@
 import Protolude hiding (to, from)
 import Prelude (String, unlines, lookup)
 
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Control.Arrow ((***))
 
 import Data.Aeson ((.=))
@@ -55,11 +59,15 @@
     -- ^ The version of the PureScript compiler which was used to generate
     -- this data. We store this in order to reject packages which are too old.
   }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData a => NFData (Package a)
+
 data NotYetKnown = NotYetKnown
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData NotYetKnown
+
 type UploadedPackage = Package NotYetKnown
 type VerifiedPackage = Package GithubUser
 
@@ -111,8 +119,10 @@
   -- Re-exported values from other modules
   , modReExports    :: [(InPackage P.ModuleName, [Declaration])]
   }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData Module
+
 data Declaration = Declaration
   { declTitle      :: Text
   , declComments   :: Maybe Text
@@ -120,8 +130,10 @@
   , declChildren   :: [ChildDeclaration]
   , declInfo       :: DeclarationInfo
   }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData Declaration
+
 -- |
 -- A value of this type contains information that is specific to a particular
 -- kind of declaration (as opposed to information which exists in all kinds of
@@ -170,8 +182,10 @@
   -- A kind declaration
   --
   | ExternKindDeclaration
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData DeclarationInfo
+
 convertFundepsToStrings :: [(Text, Maybe P.Kind)] -> [P.FunctionalDependency] -> [([Text], [Text])]
 convertFundepsToStrings args fundeps =
   map (\(P.FunctionalDependency from to) -> toArgs from to) fundeps
@@ -265,8 +279,10 @@
   , cdeclSourceSpan :: Maybe P.SourceSpan
   , cdeclInfo       :: ChildDeclarationInfo
   }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData ChildDeclaration
+
 data ChildDeclarationInfo
   -- |
   -- A type instance declaration, with its dependencies and its type.
@@ -284,8 +300,10 @@
   -- example, `pure` from `Applicative` would be `forall a. a -> f a`.
   --
   | ChildTypeClassMember P.Type
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData ChildDeclarationInfo
+
 childDeclInfoToString :: ChildDeclarationInfo -> Text
 childDeclInfoToString (ChildInstance _ _)      = "instance"
 childDeclInfoToString (ChildDataConstructor _) = "dataConstructor"
@@ -319,12 +337,16 @@
 
 newtype GithubUser
   = GithubUser { runGithubUser :: Text }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData GithubUser
+
 newtype GithubRepo
   = GithubRepo { runGithubRepo :: Text }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData GithubRepo
+
 data PackageError
   = CompilerTooOld Version Version
       -- ^ Minimum allowable version for generating data with the current
@@ -337,13 +359,17 @@
   | InvalidKind Text
   | InvalidDataDeclType Text
   | InvalidTime
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData PackageError
+
 data InPackage a
   = Local a
   | FromDep PackageName a
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData a => NFData (InPackage a)
+
 instance Functor InPackage where
   fmap f (Local x) = Local (f x)
   fmap f (FromDep pkgName x) = FromDep pkgName (f x)
@@ -370,15 +396,19 @@
   , ctxVersion              :: Version
   , ctxVersionTag           :: Text
   }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData LinksContext
+
 data DocLink = DocLink
   { linkLocation  :: LinkLocation
   , linkTitle     :: Text
   , linkNamespace :: Namespace
   }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData DocLink
+
 data LinkLocation
   -- | A link to a declaration in the same module.
   = SameModule
@@ -397,7 +427,9 @@
   -- module. In this case we only need to store the module that the builtin
   -- comes from (at the time of writing, this will only ever be "Prim").
   | BuiltinModule P.ModuleName
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
+
+instance NFData LinkLocation
 
 -- | Given a links context, the current module name, the namespace of a thing
 -- to link to, its title, and its containing module, attempt to create a
diff --git a/src/Language/PureScript/Environment.hs b/src/Language/PureScript/Environment.hs
--- a/src/Language/PureScript/Environment.hs
+++ b/src/Language/PureScript/Environment.hs
@@ -1,8 +1,12 @@
+{-# LANGUAGE DeriveGeneric #-}
+
 module Language.PureScript.Environment where
 
 import           Prelude.Compat
 import           Protolude (ordNub)
 
+import           GHC.Generics (Generic)
+import           Control.DeepSeq (NFData)
 import           Data.Aeson ((.=), (.:))
 import qualified Data.Aeson as A
 import qualified Data.Map as M
@@ -38,8 +42,10 @@
   -- ^ Type classes
   , kinds :: S.Set (Qualified (ProperName 'KindName))
   -- ^ Kinds in scope
-  } deriving Show
+  } deriving (Show, Generic)
 
+instance NFData Environment
+
 -- | Information about a type class
 data TypeClassData = TypeClassData
   { typeClassArguments :: [(Text, Maybe Kind)]
@@ -59,8 +65,10 @@
   -- typeClassArguments and typeClassDependencies.
   , typeClassCoveringSets :: S.Set (S.Set Int)
   -- ^ A sets of arguments that can be used to infer all other arguments.
-  } deriving Show
+  } deriving (Show, Generic)
 
+instance NFData TypeClassData
+
 -- | A functional dependency indicates a relationship between two sets of
 -- type arguments in a class declaration.
 data FunctionalDependency = FunctionalDependency
@@ -68,8 +76,10 @@
   -- ^ the type arguments which determine the determined type arguments
   , fdDetermined  :: [Int]
   -- ^ the determined type arguments
-  } deriving Show
+  } deriving (Show, Generic)
 
+instance NFData FunctionalDependency
+
 instance A.FromJSON FunctionalDependency where
   parseJSON = A.withObject "FunctionalDependency" $ \o ->
     FunctionalDependency
@@ -164,8 +174,10 @@
   -- ^ The name is defined in the current binding group, but is not visible
   | Defined
   -- ^ The name is defined in the another binding group, or has been made visible by a function binder
-  deriving (Show, Eq)
+  deriving (Show, Eq, Generic)
 
+instance NFData NameVisibility
+
 -- | A flag for whether a name is for an private or public value - only public values will be
 -- included in a generated externs file.
 data NameKind
@@ -176,8 +188,10 @@
   -- ^ A public value for a module member or foreing import declaration
   | External
   -- ^ A name for member introduced by foreign import
-  deriving (Show, Eq)
+  deriving (Show, Eq, Generic)
 
+instance NFData NameKind
+
 -- | The kinds of a type
 data TypeKind
   = DataType [(Text, Maybe Kind)] [(ProperName 'ConstructorName, [Type])]
@@ -190,8 +204,10 @@
   -- ^ A local type variable
   | ScopedTypeVar
   -- ^ A scoped type variable
-  deriving (Show, Eq)
+  deriving (Show, Eq, Generic)
 
+instance NFData TypeKind
+
 instance A.ToJSON TypeKind where
   toJSON (DataType args ctors) =
     A.object [ T.pack "DataType" .= A.object ["args" .= args, "ctors" .= ctors] ]
@@ -221,7 +237,9 @@
   -- ^ A standard data constructor
   | Newtype
   -- ^ A newtype constructor
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
+
+instance NFData DataDeclType
 
 showDataDeclType :: DataDeclType -> Text
 showDataDeclType Data = "data"
diff --git a/src/Language/PureScript/Errors.hs b/src/Language/PureScript/Errors.hs
--- a/src/Language/PureScript/Errors.hs
+++ b/src/Language/PureScript/Errors.hs
@@ -18,10 +18,8 @@
 import           Data.Either (partitionEithers)
 import           Data.Foldable (fold)
 import           Data.Functor.Identity (Identity(..))
-import           Data.List (transpose, nubBy, sortBy, partition, dropWhileEnd)
+import           Data.List (transpose, nubBy, sort, partition, dropWhileEnd)
 import           Data.Maybe (maybeToList, fromMaybe, mapMaybe)
-import           Data.Ord (comparing)
-import           Data.String (fromString)
 import qualified Data.Map as M
 import qualified Data.Text as T
 import           Data.Text (Text)
@@ -34,7 +32,7 @@
 import           Language.PureScript.Names
 import           Language.PureScript.Pretty
 import           Language.PureScript.Pretty.Common (endWith)
-import           Language.PureScript.PSString (PSString, decodeStringWithReplacement)
+import           Language.PureScript.PSString (decodeStringWithReplacement)
 import           Language.PureScript.Traversals
 import           Language.PureScript.Types
 import qualified Language.PureScript.Publish.BoxesHelpers as BoxHelpers
@@ -567,15 +565,11 @@
             -- Put the common labels last
             sortRows' :: ([(Label, Type)], Type) -> ([(Label, Type)], Type) -> (Type, Type)
             sortRows' (s1, r1) (s2, r2) =
-              let common :: [(Label, (Type, Type))]
-                  common = sortBy (comparing fst) [ (name, (t1, t2)) | (name, t1) <- s1, (name', t2) <- s2, name == name' ]
-
-                  sd1, sd2 :: [(Label, Type)]
-                  sd1 = [ (name, t1) | (name, t1) <- s1, name `notElem` map fst s2 ]
-                  sd2 = [ (name, t2) | (name, t2) <- s2, name `notElem` map fst s1 ]
-              in ( rowFromList (sortBy (comparing fst) sd1 ++ map (fst &&& fst . snd) common, r1)
-                 , rowFromList (sortBy (comparing fst) sd2 ++ map (fst &&& snd . snd) common, r2)
-                 )
+                  let (common1, unique1) = partition (flip elem s2) s1
+                      (common2, unique2) = partition (flip elem s1) s2
+                  in ( rowFromList (sort unique1 ++ sort common1, r1)
+                     , rowFromList (sort unique2 ++ sort common2, r2)
+                     )
         in paras [ line "Could not match type"
                  , markCodeBox $ indent $ typeAsBox sorted1
                  , line "with type"
@@ -1313,15 +1307,14 @@
   whiteSpace = all isSpace
 
 toTypelevelString :: Type -> Maybe Box.Box
-toTypelevelString t = (Box.text . decodeStringWithReplacement) <$> toTypelevelString' t
-  where
-  toTypelevelString' :: Type -> Maybe PSString
-  toTypelevelString' (TypeLevelString s) = Just s
-  toTypelevelString' (TypeApp (TypeConstructor f) x)
-    | f == primName "TypeString" = Just $ fromString $ prettyPrintType x
-  toTypelevelString' (TypeApp (TypeApp (TypeConstructor f) x) ret)
-    | f == primName "TypeConcat" = toTypelevelString' x <> toTypelevelString' ret
-  toTypelevelString' _ = Nothing
+toTypelevelString (TypeLevelString s) =
+  Just . Box.text $ decodeStringWithReplacement s
+toTypelevelString (TypeApp (TypeConstructor f) x)
+  | f == primName "TypeString" = Just (typeAsBox x)
+toTypelevelString (TypeApp (TypeApp (TypeConstructor f) x) ret)
+  | f == primName "TypeConcat" =
+    (Box.<>) <$> toTypelevelString x <*> toTypelevelString ret
+toTypelevelString _ = Nothing
 
 -- | Rethrow an error with a more detailed error message in the case of failure
 rethrow :: (MonadError e m) => (e -> e) -> m a -> m a
diff --git a/src/Language/PureScript/Ide/Imports.hs b/src/Language/PureScript/Ide/Imports.hs
--- a/src/Language/PureScript/Ide/Imports.hs
+++ b/src/Language/PureScript/Ide/Imports.hs
@@ -85,7 +85,7 @@
 parseImportsFromFile' :: (MonadIO m, MonadError IdeError m) =>
                         FilePath -> m (P.ModuleName, [Text], [Import], [Text])
 parseImportsFromFile' fp = do
-  file <- ideReadFile fp
+  file <- ideReadTextFile fp
   case sliceImportSection (T.lines file) of
     Right res -> pure res
     Left err -> throwError (GeneralError err)
diff --git a/src/Language/PureScript/Ide/Types.hs b/src/Language/PureScript/Ide/Types.hs
--- a/src/Language/PureScript/Ide/Types.hs
+++ b/src/Language/PureScript/Ide/Types.hs
@@ -229,7 +229,7 @@
   toJSON (PursuitResult resp) = encodeSuccess resp
   toJSON (ImportList (moduleName, imports)) = object [ "resultType" .= ("success" :: Text)
                                                      , "result" .= object [ "imports" .= map encodeImport imports
-                                                                          , "moduleName" .= moduleName]]
+                                                                          , "moduleName" .= P.runModuleName moduleName]]
   toJSON (ModuleList modules) = encodeSuccess modules
   toJSON (RebuildSuccess warnings) = encodeSuccess (P.toJSONErrors False P.Warning warnings)
 
diff --git a/src/Language/PureScript/Ide/Util.hs b/src/Language/PureScript/Ide/Util.hs
--- a/src/Language/PureScript/Ide/Util.hs
+++ b/src/Language/PureScript/Ide/Util.hs
@@ -28,6 +28,7 @@
   , identT
   , opNameT
   , ideReadFile
+  , ideReadTextFile
   , module Language.PureScript.Ide.Logging
   ) where
 
@@ -37,6 +38,7 @@
 import           Control.Lens                        hiding ((&), op)
 import           Data.Aeson
 import qualified Data.Text                           as T
+import qualified Data.Text.IO                        as TIO
 import qualified Data.Text.Lazy                      as TL
 import           Data.Text.Lazy.Encoding             (decodeUtf8, encodeUtf8)
 import qualified Language.PureScript                 as P
@@ -129,10 +131,25 @@
 opNameT :: Iso' (P.OpName a) Text
 opNameT = iso P.runOpName P.OpName
 
-ideReadFile :: (MonadIO m, MonadError IdeError m) => FilePath -> m Text
-ideReadFile fp = do
-  contents :: Either IOException Text <- liftIO (try (readUTF8FileT fp))
+ideReadFile'
+  :: (MonadIO m, MonadError IdeError m)
+  => (FilePath -> IO Text)
+  -> FilePath
+  -> m Text
+ideReadFile' fileReader fp = do
+  contents :: Either IOException Text <- liftIO (try (fileReader fp))
   either
     (\_ -> throwError (GeneralError ("Couldn't find file at: " <> T.pack fp)))
     pure
     contents
+
+ideReadFile :: (MonadIO m, MonadError IdeError m) => FilePath -> m Text
+ideReadFile = ideReadFile' readUTF8FileT
+
+-- | This function is to be used over @ideReadFile@ when the result is not just
+-- passed on to the PureScript parser, but also needs to be treated as lines of
+-- text. Because @ideReadFile@ reads the file as ByteString in @BinaryMode@
+-- rather than @TextMode@ line endings get mangled on Windows otherwise. This is
+-- irrelevant for parsing, because the Lexer strips these additional @\r@'s.
+ideReadTextFile :: (MonadIO m, MonadError IdeError m) => FilePath -> m Text
+ideReadTextFile = ideReadFile' TIO.readFile
diff --git a/src/Language/PureScript/Ide/Watcher.hs b/src/Language/PureScript/Ide/Watcher.hs
--- a/src/Language/PureScript/Ide/Watcher.hs
+++ b/src/Language/PureScript/Ide/Watcher.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE PackageImports #-}
 -----------------------------------------------------------------------------
 --
 -- Module      : Language.PureScript.Ide.Watcher
@@ -16,38 +17,40 @@
  ( watcher
  ) where
 
-import           Protolude
+import                Protolude
 
-import           Control.Concurrent.STM
-import           Language.PureScript.Ide.Externs
-import           Language.PureScript.Ide.State
-import           Language.PureScript.Ide.Types
-import           Language.PureScript.Ide.Util
-import           System.FilePath
-import           System.FSNotify
+import                Control.Concurrent.STM
+import "monad-logger" Control.Monad.Logger
+import                Language.PureScript.Ide.Externs
+import                Language.PureScript.Ide.State
+import                Language.PureScript.Ide.Types
+import                Language.PureScript.Ide.Util
+import                System.FSNotify
+import                System.FilePath
 
 -- | Reloads an ExternsFile from Disc. If the Event indicates the ExternsFile
 -- was deleted we don't do anything.
-reloadFile :: TVar IdeState -> Event -> IO ()
-reloadFile _ Removed{} = pure ()
-reloadFile ref ev = do
+reloadFile :: IdeLogLevel -> TVar IdeState -> Event -> IO ()
+reloadFile _ _ Removed{} = pure ()
+reloadFile logLevel ref ev = runLogger logLevel $ do
   let fp = eventPath ev
-  ef' <- runLogger LogDefault (runExceptT (readExternFile fp))
+  ef' <- runExceptT (readExternFile fp)
   case ef' of
-    Left _ -> pure ()
+    Left err ->
+      logErrorN ("Failed to reload file at: " <> toS fp <> " with error: " <> show err)
     Right ef -> do
-      void $ atomically (insertExternsSTM ref ef *> populateStage3STM ref)
-      putStrLn ("Reloaded File at: " ++ fp)
+      lift $ void $ atomically (insertExternsSTM ref ef *> populateStage3STM ref)
+      logDebugN ("Reloaded File at: " <> toS fp)
 
 -- | Installs filewatchers for the given directory and reloads ExternsFiles when
 -- they change on disc
-watcher :: Bool -> TVar IdeState -> FilePath -> IO ()
-watcher polling stateVar fp =
+watcher :: Bool -> IdeLogLevel -> TVar IdeState -> FilePath -> IO ()
+watcher polling logLevel stateVar fp =
   withManagerConf
     (defaultConfig { confDebounce = NoDebounce
                    , confUsePolling = polling
                    }) $ \mgr -> do
       _ <- watchTree mgr fp
         (\ev -> takeFileName (eventPath ev) == "externs.json")
-        (reloadFile stateVar)
+        (reloadFile logLevel stateVar)
       forever (threadDelay 100000)
diff --git a/src/Language/PureScript/Kinds.hs b/src/Language/PureScript/Kinds.hs
--- a/src/Language/PureScript/Kinds.hs
+++ b/src/Language/PureScript/Kinds.hs
@@ -1,7 +1,11 @@
+{-# LANGUAGE DeriveGeneric #-}
+
 module Language.PureScript.Kinds where
 
 import Prelude.Compat
 
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Data.Text (Text)
 import qualified Data.Text as T
 import Data.Aeson.BetterErrors (Parse, key, asText, asIntegral, nth, fromAesonParser, toAesonParser, throwCustomError)
@@ -21,7 +25,9 @@
   | FunKind Kind Kind
   -- | A named kind
   | NamedKind (Qualified (ProperName 'KindName))
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
+
+instance NFData Kind
 
 -- This is equivalent to the derived Aeson ToJSON instance, except that we
 -- write it out manually so that we can define a parser which is
diff --git a/src/Language/PureScript/Label.hs b/src/Language/PureScript/Label.hs
--- a/src/Language/PureScript/Label.hs
+++ b/src/Language/PureScript/Label.hs
@@ -1,7 +1,11 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE DeriveGeneric #-}
+
 module Language.PureScript.Label (Label(..)) where
 
 import Prelude.Compat hiding (lex)
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Data.Monoid ()
 import Data.String (IsString(..))
 import qualified Data.Aeson as A
@@ -13,4 +17,6 @@
 -- because records are indexable by PureScript strings at runtime.
 --
 newtype Label = Label { runLabel :: PSString }
-  deriving (Show, Eq, Ord, IsString, Monoid, A.ToJSON, A.FromJSON)
+  deriving (Show, Eq, Ord, IsString, Monoid, A.ToJSON, A.FromJSON, Generic)
+
+instance NFData Label
diff --git a/src/Language/PureScript/Names.hs b/src/Language/PureScript/Names.hs
--- a/src/Language/PureScript/Names.hs
+++ b/src/Language/PureScript/Names.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE DeriveGeneric #-}
 
 -- |
 -- Data types for names
@@ -8,7 +9,9 @@
 import Prelude.Compat
 
 import Control.Monad.Supply.Class
+import Control.DeepSeq (NFData)
 
+import GHC.Generics (Generic)
 import Data.Aeson
 import Data.Aeson.TH
 import Data.Monoid ((<>))
@@ -25,8 +28,10 @@
   | TyClassName (ProperName 'ClassName)
   | ModName ModuleName
   | KiName (ProperName 'KindName)
-  deriving (Eq, Ord, Show)
+  deriving (Eq, Ord, Show, Generic)
 
+instance NFData Name
+
 getIdentName :: Name -> Maybe Ident
 getIdentName (IdentName name) = Just name
 getIdentName _ = Nothing
@@ -67,8 +72,10 @@
   -- A generated name for an identifier
   --
   | GenIdent (Maybe Text) Integer
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData Ident
+
 runIdent :: Ident -> Text
 runIdent (Ident i) = i
 runIdent (GenIdent Nothing n) = "$" <> T.pack (show n)
@@ -87,8 +94,10 @@
 -- Operator alias names.
 --
 newtype OpName (a :: OpNameType) = OpName { runOpName :: Text }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData (OpName a)
+
 instance ToJSON (OpName a) where
   toJSON = toJSON . runOpName
 
@@ -107,8 +116,10 @@
 -- Proper names, i.e. capitalized names for e.g. module names, type//data constructors.
 --
 newtype ProperName (a :: ProperNameType) = ProperName { runProperName :: Text }
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData (ProperName a)
+
 instance ToJSON (ProperName a) where
   toJSON = toJSON . runProperName
 
@@ -137,8 +148,10 @@
 -- Module names
 --
 newtype ModuleName = ModuleName [ProperName 'Namespace]
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData ModuleName
+
 runModuleName :: ModuleName -> Text
 runModuleName (ModuleName pns) = T.intercalate "." (runProperName <$> pns)
 
@@ -154,7 +167,9 @@
 -- A qualified name, i.e. a name with an optional module name
 --
 data Qualified a = Qualified (Maybe ModuleName) a
-  deriving (Show, Eq, Ord, Functor)
+  deriving (Show, Eq, Ord, Functor, Generic)
+
+instance NFData a => NFData (Qualified a)
 
 showQualified :: (a -> Text) -> Qualified a -> Text
 showQualified f (Qualified Nothing a) = f a
diff --git a/src/Language/PureScript/PSString.hs b/src/Language/PureScript/PSString.hs
--- a/src/Language/PureScript/PSString.hs
+++ b/src/Language/PureScript/PSString.hs
@@ -1,5 +1,7 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE DeriveGeneric #-}
+
 module Language.PureScript.PSString
   ( PSString
   , toUTF16CodeUnits
@@ -12,6 +14,8 @@
   ) where
 
 import Prelude.Compat
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Control.Exception (try, evaluate)
 import Control.Applicative ((<|>))
 import Data.Char (chr)
@@ -48,7 +52,9 @@
 -- and arrays of UTF-16 code units (integers) otherwise.
 --
 newtype PSString = PSString { toUTF16CodeUnits :: [Word16] }
-  deriving (Eq, Ord, Monoid)
+  deriving (Eq, Ord, Monoid, Generic)
+
+instance NFData PSString
 
 instance Show PSString where
   show = show . codePoints
diff --git a/src/Language/PureScript/TypeChecker/Entailment.hs b/src/Language/PureScript/TypeChecker/Entailment.hs
--- a/src/Language/PureScript/TypeChecker/Entailment.hs
+++ b/src/Language/PureScript/TypeChecker/Entailment.hs
@@ -152,8 +152,10 @@
     solve constraint
   where
     forClassName :: InstanceContext -> Qualified (ProperName 'ClassName) -> [Type] -> [TypeClassDict]
-    forClassName _ C.Warn [msg] =
-      [TypeClassDictionaryInScope (WarnInstance msg) [] C.Warn [msg] Nothing]
+    forClassName ctx cn@C.Warn [msg] =
+      -- Prefer a warning dictionary in scope if there is one available.
+      -- This allows us to defer a warning by propagating the constraint.
+      findDicts ctx cn Nothing ++ [TypeClassDictionaryInScope (WarnInstance msg) [] C.Warn [msg] Nothing]
     forClassName _ C.IsSymbol [TypeLevelString sym] =
       [TypeClassDictionaryInScope (IsSymbolInstance sym) [] C.IsSymbol [TypeLevelString sym] Nothing]
     forClassName _ C.CompareSymbol [arg0@(TypeLevelString lhs), arg1@(TypeLevelString rhs), _] =
diff --git a/src/Language/PureScript/TypeClassDictionaries.hs b/src/Language/PureScript/TypeClassDictionaries.hs
--- a/src/Language/PureScript/TypeClassDictionaries.hs
+++ b/src/Language/PureScript/TypeClassDictionaries.hs
@@ -1,9 +1,12 @@
 {-# LANGUAGE DeriveFoldable    #-}
 {-# LANGUAGE DeriveTraversable #-}
+{-# LANGUAGE DeriveGeneric     #-}
 module Language.PureScript.TypeClassDictionaries where
 
 import Prelude.Compat
 
+import GHC.Generics (Generic)
+import Control.DeepSeq (NFData)
 import Data.Monoid ((<>))
 import Data.Text (Text, pack)
 
@@ -26,7 +29,9 @@
     -- | Type class dependencies which must be satisfied to construct this dictionary
     , tcdDependencies :: Maybe [Constraint]
     }
-    deriving (Show, Functor, Foldable, Traversable)
+    deriving (Show, Functor, Foldable, Traversable, Generic)
+
+instance NFData v => NFData (TypeClassDictionaryInScope v)
 
 type NamedDict = TypeClassDictionaryInScope (Qualified Ident)
 
diff --git a/src/Language/PureScript/Types.hs b/src/Language/PureScript/Types.hs
--- a/src/Language/PureScript/Types.hs
+++ b/src/Language/PureScript/Types.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE DeriveGeneric #-}
 
 -- |
 -- Data types for types
@@ -10,6 +11,7 @@
 import Protolude (ordNub)
 
 import Control.Arrow (first)
+import Control.DeepSeq (NFData)
 import Control.Monad ((<=<))
 import qualified Data.Aeson as A
 import qualified Data.Aeson.TH as A
@@ -19,6 +21,7 @@
 import Data.Monoid ((<>))
 import Data.Text (Text)
 import qualified Data.Text as T
+import GHC.Generics (Generic)
 
 import Language.PureScript.AST.SourcePos
 import Language.PureScript.Kinds
@@ -30,8 +33,10 @@
 -- An identifier for the scope of a skolem variable
 --
 newtype SkolemScope = SkolemScope { runSkolemScope :: Int }
-  deriving (Show, Eq, Ord, A.ToJSON, A.FromJSON)
+  deriving (Show, Eq, Ord, A.ToJSON, A.FromJSON, Generic)
 
+instance NFData SkolemScope
+
 -- |
 -- The type of types
 --
@@ -78,8 +83,10 @@
   -- Note: although it seems this constructor is not used, it _is_ useful,
   -- since it prevents certain traversals from matching.
   | ParensInType Type
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData Type
+
 -- | Additional data relevant to type class constraints
 data ConstraintData
   = PartialConstraintData [[Text]] Bool
@@ -88,8 +95,10 @@
   -- not matched, and a flag indicating whether the list was truncated or not.
   -- Note: we use 'Text' here because using 'Binder' would introduce a cyclic
   -- dependency in the module graph.
-  deriving (Show, Eq, Ord)
+  deriving (Show, Eq, Ord, Generic)
 
+instance NFData ConstraintData
+
 -- | A typeclass constraint
 data Constraint = Constraint
   { constraintClass :: Qualified (ProperName 'ClassName)
@@ -98,7 +107,9 @@
   -- ^ type arguments
   , constraintData  :: Maybe ConstraintData
   -- ^ additional data relevant to this constraint
-  } deriving (Show, Eq, Ord)
+  } deriving (Show, Eq, Ord, Generic)
+
+instance NFData Constraint
 
 mapConstraintArgs :: ([Type] -> [Type]) -> Constraint -> Constraint
 mapConstraintArgs f c = c { constraintArgs = f (constraintArgs c) }
diff --git a/tests/TestDocs.hs b/tests/TestDocs.hs
--- a/tests/TestDocs.hs
+++ b/tests/TestDocs.hs
@@ -398,6 +398,10 @@
   , ("DocComments",
       [ ShouldHaveDocComment (n "DocComments") "example" "    example == 0"
       ])
+
+  , ("TypeLevelString",
+      [ ShouldBeDocumented (n "TypeLevelString") "Foo" ["fooBar"]
+      ])
   ]
 
   where