diff --git a/purescript.cabal b/purescript.cabal
index 84458234c4..36c07b51ad 100644
--- a/purescript.cabal
+++ b/purescript.cabal
@@ -342,6 +342,7 @@ library
     Language.PureScript.Sugar.Names.Env
     Language.PureScript.Sugar.Names.Exports
     Language.PureScript.Sugar.Names.Imports
+    Language.PureScript.Sugar.Names.Requalify
     Language.PureScript.Sugar.ObjectWildcards
     Language.PureScript.Sugar.Operators
     Language.PureScript.Sugar.Operators.Binders
diff --git a/src/Language/PureScript/Errors.hs b/src/Language/PureScript/Errors.hs
index eecbfc3ce3..db524e154b 100644
--- a/src/Language/PureScript/Errors.hs
+++ b/src/Language/PureScript/Errors.hs
@@ -104,6 +104,7 @@ data SimpleErrorMessage
   | UndefinedTypeVariable (ProperName 'TypeName)
   | PartiallyAppliedSynonym (Qualified (ProperName 'TypeName))
   | EscapedSkolem Text (Maybe SourceSpan) SourceType
+  | TypeConstructorsDoNotUnify ModuleName SourceType ModuleName SourceType
   | TypesDoNotUnify SourceType SourceType
   | KindsDoNotUnify SourceType SourceType
   | ConstrainedTypeUnified SourceType SourceType
@@ -283,6 +284,7 @@ errorCode em = case unwrapErrorMessage em of
   UndefinedTypeVariable{} -> "UndefinedTypeVariable"
   PartiallyAppliedSynonym{} -> "PartiallyAppliedSynonym"
   EscapedSkolem{} -> "EscapedSkolem"
+  TypeConstructorsDoNotUnify{} -> "TypeConstructorsDoNotUnify"
   TypesDoNotUnify{} -> "TypesDoNotUnify"
   KindsDoNotUnify{} -> "KindsDoNotUnify"
   ConstrainedTypeUnified{} -> "ConstrainedTypeUnified"
@@ -410,6 +412,13 @@ addHint hint = addHints [hint]
 addHints :: [ErrorMessageHint] -> MultipleErrors -> MultipleErrors
 addHints hints = onErrorMessages $ \(ErrorMessage hints' se) -> ErrorMessage (hints ++ hints') se
 
+mkTypesDoNotUnify :: SourceType -> SourceType -> SimpleErrorMessage
+mkTypesDoNotUnify
+  t1@(TypeConstructor _ (Qualified (ByModuleName mn1) _))
+  t2@(TypeConstructor _ (Qualified (ByModuleName mn2) _))
+  = TypeConstructorsDoNotUnify mn1 t1 mn2 t2
+mkTypesDoNotUnify t1 t2 = TypesDoNotUnify t1 t2
+
 -- | A map from rigid type variable name/unknown variable pairs to new variables.
 data TypeMap = TypeMap
   { umSkolemMap   :: M.Map Int (String, Int, Maybe SourceSpan)
@@ -462,7 +471,9 @@ onTypesInErrorMessageM :: Applicative m => (SourceType -> m SourceType) -> Error
 onTypesInErrorMessageM f (ErrorMessage hints simple) = ErrorMessage <$> traverse gHint hints <*> gSimple simple
   where
   gSimple (InfiniteType t) = InfiniteType <$> f t
+  gSimple (TypeConstructorsDoNotUnify mn1 t1 mn2 t2) = TypeConstructorsDoNotUnify mn1 <$> f t1 <*> pure mn2 <*> f t2
   gSimple (TypesDoNotUnify t1 t2) = TypesDoNotUnify <$> f t1 <*> f t2
+  gSimple (KindsDoNotUnify t1 t2) = KindsDoNotUnify <$> f t1 <*> f t2
   gSimple (ConstrainedTypeUnified t1 t2) = ConstrainedTypeUnified <$> f t1 <*> f t2
   gSimple (ExprDoesNotHaveType e t) = ExprDoesNotHaveType e <$> f t
   gSimple (InvalidInstanceHead t) = InvalidInstanceHead <$> f t
@@ -855,6 +866,16 @@ prettyPrintSingleError (PPEOptions codeColor full level showDocs relPath fileCon
                  , line "with type"
                  , row2Box
                  ]
+    renderSimpleErrorMessage (TypeConstructorsDoNotUnify mn1 u1 mn2 u2)
+      = let (row1Box, row2Box) = printRows u1 u2
+
+        in paras [ line "Could not match type"
+                 , row1Box
+                 , line $ "(defined in module " <> markCode (runModuleName mn1) <> ")"
+                 , line "with type"
+                 , row2Box
+                 , line $ "(defined in module " <> markCode (runModuleName mn2) <> ")"
+                 ]
 
     renderSimpleErrorMessage (KindsDoNotUnify k1 k2) =
       paras [ line "Could not match kind"
@@ -1564,14 +1585,13 @@ prettyPrintSingleError (PPEOptions codeColor full level showDocs relPath fileCon
     -- If verbose print all rows else only print unique rows
     printRows :: Type a -> Type a -> (Box.Box, Box.Box)
     printRows r1 r2 = case (full, r1, r2) of
-      (True, _ , _) -> (printRow typeAsBox r1, printRow typeAsBox r2)
+      (True, _ , _) -> (printRow prettyTypeWithDepth r1, printRow prettyTypeWithDepth r2)
 
       (_, RCons{}, RCons{}) ->
         let (sorted1, sorted2) = filterRows (rowToList r1) (rowToList r2)
         in (printRow typeDiffAsBox sorted1, printRow typeDiffAsBox sorted2)
 
-      (_, _, _) -> (printRow typeAsBox r1, printRow typeAsBox r2)
-
+      (_, _, _) -> (printRow prettyTypeWithDepth r1, printRow prettyTypeWithDepth r2)
 
     -- Keep the unique labels only
     filterRows :: ([RowListItem a], Type a) -> ([RowListItem a], Type a) -> (Type a, Type a)
@@ -1646,13 +1666,15 @@ prettyPrintSingleError (PPEOptions codeColor full level showDocs relPath fileCon
 
   prettyTypeWithDepth :: Int -> Type a -> Box.Box
   prettyTypeWithDepth depth
-    | full = typeAsBox depth
-    | otherwise = typeAsBox depth . eraseForAllKindAnnotations . eraseKindApps
+    | full = typeAsBoxWith depth prettyOptions
+    | otherwise = typeAsBoxWith depth prettyOptions . eraseForAllKindAnnotations . eraseKindApps
 
   prettyTypeAtom :: Type a -> Box.Box
   prettyTypeAtom
-    | full = typeAtomAsBox prettyDepth
-    | otherwise = typeAtomAsBox prettyDepth . eraseForAllKindAnnotations . eraseKindApps
+    | full = typeAtomAsBoxWith prettyDepth prettyOptions
+    | otherwise = typeAtomAsBoxWith prettyDepth prettyOptions . eraseForAllKindAnnotations . eraseKindApps
+
+  prettyOptions = defaultTypeRenderOptions { troDisqualifyNames = False }
 
   levelText :: Text
   levelText = case level of
@@ -1684,6 +1706,10 @@ prettyPrintSingleError (PPEOptions codeColor full level showDocs relPath fileCon
       where
       isCheckHint ErrorCheckingType{} = True
       isCheckHint _ = False
+    stripRedundantHints TypeConstructorsDoNotUnify{} = stripFirst isUnifyHint
+      where
+      isUnifyHint ErrorUnifyingTypes{} = True
+      isUnifyHint _ = False
     stripRedundantHints TypesDoNotUnify{} = stripFirst isUnifyHint
       where
       isUnifyHint ErrorUnifyingTypes{} = True
diff --git a/src/Language/PureScript/Make.hs b/src/Language/PureScript/Make.hs
index d9e7157f16..efffb80e60 100644
--- a/src/Language/PureScript/Make.hs
+++ b/src/Language/PureScript/Make.hs
@@ -41,6 +41,7 @@ import           Language.PureScript.ModuleDependencies
 import           Language.PureScript.Names
 import           Language.PureScript.Renamer
 import           Language.PureScript.Sugar
+import           Language.PureScript.Sugar.Names.Requalify
 import           Language.PureScript.TypeChecker
 import           Language.PureScript.Make.BuildPlan
 import qualified Language.PureScript.Make.BuildPlan as BuildPlan
@@ -87,13 +88,14 @@ rebuildModuleWithIndex
 rebuildModuleWithIndex MakeActions{..} exEnv externs m@(Module _ _ moduleName _ _) moduleIndex = do
   progress $ CompilingModule moduleName moduleIndex
   let env = foldl' (flip applyExternsFileToEnvironment) initEnvironment externs
-      withPrim = importPrim m
+      withPrim = importPrim m -- TODO: are we importing Prim twice
   lint withPrim
 
   ((Module ss coms _ elaborated exps, env'), nextVar) <- runSupplyT 0 $ do
     (desugared, (exEnv', usedImports)) <- runStateT (desugar externs withPrim) (exEnv, mempty)
     let modulesExports = (\(_, _, exports) -> exports) <$> exEnv'
-    (checked, CheckState{..}) <- runStateT (typeCheckModule modulesExports desugared) $ emptyCheckState env
+        localImports = maybe (internalError "no local imports") (\(_, imports, _) -> imports) $ M.lookup moduleName exEnv'
+    (checked, CheckState{..}) <- rethrow (requalifyTypesInErrors localImports) $ runStateT (typeCheckModule modulesExports desugared) $ emptyCheckState env
     let usedImports' = foldl' (flip $ \(fromModuleName, newtypeCtorName) ->
           M.alter (Just . (fmap DctorName newtypeCtorName :) . fold) fromModuleName) usedImports checkConstructorImportsForCoercible
     -- Imports cannot be linted before type checking because we need to
diff --git a/src/Language/PureScript/Names.hs b/src/Language/PureScript/Names.hs
index 16dda5e1bb..20fc554de5 100644
--- a/src/Language/PureScript/Names.hs
+++ b/src/Language/PureScript/Names.hs
@@ -127,7 +127,7 @@ isPlainIdent _ = False
 -- Operator alias names.
 --
 newtype OpName (a :: OpNameType) = OpName { runOpName :: Text }
-  deriving (Show, Eq, Ord, Generic)
+  deriving (Show, Read, Eq, Ord, Generic)
 
 instance NFData (OpName a)
 instance Serialise (OpName a)
@@ -156,7 +156,7 @@ coerceOpName = OpName . runOpName
 -- 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, Generic)
+  deriving (Show, Read, Eq, Ord, Generic)
 
 instance NFData (ProperName a)
 instance Serialise (ProperName a)
@@ -188,7 +188,7 @@ coerceProperName = ProperName . runProperName
 -- Module names
 --
 newtype ModuleName = ModuleName Text
-  deriving (Show, Eq, Ord, Generic)
+  deriving (Show, Read, Eq, Ord, Generic)
   deriving newtype Serialise
 
 instance NFData ModuleName
diff --git a/src/Language/PureScript/Pretty/Types.hs b/src/Language/PureScript/Pretty/Types.hs
index d7c90374c3..d5ad6bf140 100644
--- a/src/Language/PureScript/Pretty/Types.hs
+++ b/src/Language/PureScript/Pretty/Types.hs
@@ -7,13 +7,17 @@
 module Language.PureScript.Pretty.Types
   ( PrettyPrintType(..)
   , PrettyPrintConstraint
+  , TypeRenderOptions(..)
+  , defaultTypeRenderOptions
   , convertPrettyPrintType
   , typeAsBox
+  , typeAsBoxWith
   , typeDiffAsBox
   , prettyPrintType
   , prettyPrintTypeWithUnicode
   , prettyPrintSuggestedType
   , typeAtomAsBox
+  , typeAtomAsBoxWith
   , prettyPrintTypeAtom
   , prettyPrintLabel
   , prettyPrintObjectKey
@@ -181,7 +185,7 @@ explicitParens = mkPattern match
   match _ = Nothing
 
 matchTypeAtom :: TypeRenderOptions -> Pattern () PrettyPrintType Box
-matchTypeAtom tro@TypeRenderOptions{troSuggesting = suggesting} =
+matchTypeAtom tro@TypeRenderOptions{troSuggesting = suggesting, troDisqualifyNames = disqualifying} =
     typeLiterals <+> fmap ((`before` text ")") . (text "(" <>)) (matchType tro)
   where
     typeLiterals :: Pattern () PrettyPrintType Box
@@ -190,7 +194,10 @@ matchTypeAtom tro@TypeRenderOptions{troSuggesting = suggesting} =
       match (PPTypeVar var _) = Just $ text $ T.unpack var
       match (PPTypeLevelString s) = Just $ text $ T.unpack $ prettyPrintString s
       match (PPTypeLevelInt n) = Just $ text $ show n
-      match (PPTypeConstructor ctor) = Just $ text $ T.unpack $ runProperName $ disqualify ctor
+      match (PPTypeConstructor ctor) = Just $ text $ T.unpack $
+        if disqualifying
+          then runProperName $ disqualify ctor
+          else showQualified runProperName ctor
       match (PPTUnknown u)
         | suggesting = Just $ text "_"
         | otherwise = Just $ text $ 't' : show u
@@ -238,10 +245,16 @@ forall_ = mkPattern match
   match (PPForAll idents ty) = Just (map (first T.unpack) idents, ty)
   match _ = Nothing
 
-typeAtomAsBox' :: PrettyPrintType -> Box
-typeAtomAsBox'
+typeAtomAsBoxWith' :: TypeRenderOptions -> PrettyPrintType -> Box
+typeAtomAsBoxWith' tro
   = fromMaybe (internalError "Incomplete pattern")
-  . PA.pattern (matchTypeAtom defaultOptions) ()
+  . PA.pattern (matchTypeAtom tro) ()
+
+typeAtomAsBox' :: PrettyPrintType -> Box
+typeAtomAsBox' = typeAtomAsBoxWith' defaultTypeRenderOptions
+
+typeAtomAsBoxWith :: Int -> TypeRenderOptions -> Type a -> Box
+typeAtomAsBoxWith maxDepth tro = typeAtomAsBoxWith' tro . convertPrettyPrintType maxDepth
 
 typeAtomAsBox :: Int -> Type a -> Box
 typeAtomAsBox maxDepth = typeAtomAsBox' . convertPrettyPrintType maxDepth
@@ -250,14 +263,22 @@ typeAtomAsBox maxDepth = typeAtomAsBox' . convertPrettyPrintType maxDepth
 prettyPrintTypeAtom :: Int -> Type a -> String
 prettyPrintTypeAtom maxDepth = render . typeAtomAsBox maxDepth
 
+typeAsBoxWith' :: TypeRenderOptions -> PrettyPrintType -> Box
+typeAsBoxWith' tro
+  = fromMaybe (internalError "Incomplete pattern")
+  . PA.pattern (matchType tro) ()
+
+typeAsBoxWith :: Int -> TypeRenderOptions -> Type a -> Box
+typeAsBoxWith maxDepth tro = typeAsBoxWith' tro . convertPrettyPrintType maxDepth
+
 typeAsBox' :: PrettyPrintType -> Box
-typeAsBox' = typeAsBoxImpl defaultOptions
+typeAsBox' = typeAsBoxWith' defaultTypeRenderOptions
 
 typeAsBox :: Int -> Type a -> Box
 typeAsBox maxDepth = typeAsBox' . convertPrettyPrintType maxDepth
 
 typeDiffAsBox' :: PrettyPrintType -> Box
-typeDiffAsBox' = typeAsBoxImpl diffOptions
+typeDiffAsBox' = typeAsBoxWith' diffOptions
 
 typeDiffAsBox :: Int -> Type a -> Box
 typeDiffAsBox maxDepth = typeDiffAsBox' . convertPrettyPrintType maxDepth
@@ -266,28 +287,29 @@ data TypeRenderOptions = TypeRenderOptions
   { troSuggesting :: Bool
   , troUnicode :: Bool
   , troRowAsDiff :: Bool
+  , troDisqualifyNames :: Bool
   }
 
-suggestingOptions :: TypeRenderOptions
-suggestingOptions = TypeRenderOptions True False False
+defaultTypeRenderOptions :: TypeRenderOptions
+defaultTypeRenderOptions = TypeRenderOptions
+  { troSuggesting = False
+  , troUnicode = False
+  , troRowAsDiff = False
+  , troDisqualifyNames = True
+  }
 
-defaultOptions :: TypeRenderOptions
-defaultOptions = TypeRenderOptions False False False
+suggestingOptions :: TypeRenderOptions
+suggestingOptions = defaultTypeRenderOptions { troSuggesting = True }
 
 diffOptions :: TypeRenderOptions
-diffOptions = TypeRenderOptions False False True
+diffOptions = defaultTypeRenderOptions { troRowAsDiff = True }
 
 unicodeOptions :: TypeRenderOptions
-unicodeOptions = TypeRenderOptions False True False
-
-typeAsBoxImpl :: TypeRenderOptions -> PrettyPrintType -> Box
-typeAsBoxImpl tro
-  = fromMaybe (internalError "Incomplete pattern")
-  . PA.pattern (matchType tro) ()
+unicodeOptions = defaultTypeRenderOptions { troUnicode = True }
 
 -- | Generate a pretty-printed string representing a 'Type'
 prettyPrintType :: Int -> Type a -> String
-prettyPrintType = flip prettyPrintType' defaultOptions
+prettyPrintType = flip prettyPrintType' defaultTypeRenderOptions
 
 -- | Generate a pretty-printed string representing a 'Type' using unicode
 -- symbols where applicable
@@ -299,7 +321,7 @@ prettyPrintSuggestedType :: Type a -> String
 prettyPrintSuggestedType = prettyPrintType' maxBound suggestingOptions
 
 prettyPrintType' :: Int -> TypeRenderOptions -> Type a -> String
-prettyPrintType' maxDepth tro = render . typeAsBoxImpl tro . convertPrettyPrintType maxDepth
+prettyPrintType' maxDepth tro = render . typeAsBoxWith' tro . convertPrettyPrintType maxDepth
 
 prettyPrintLabel :: Label -> Text
 prettyPrintLabel (Label s) =
diff --git a/src/Language/PureScript/Sugar/Names/Requalify.hs b/src/Language/PureScript/Sugar/Names/Requalify.hs
new file mode 100644
index 0000000000..d1e4a46880
--- /dev/null
+++ b/src/Language/PureScript/Sugar/Names/Requalify.hs
@@ -0,0 +1,194 @@
+-- | This module provides functions for "re-qualifying" names in a type given
+-- an Imports record, so that they can be displayed unambiguously in
+-- diagnostics and suggestions without unnecessary qualification. That is,
+-- given a fully qualified name like `Foo.Bar.X`, this module lets you go to
+-- simply `X` (no qualification) if the given Imports record includes an open
+-- import for `X` from `Foo.Bar`, or alternatively if `Foo.Bar` is imported
+-- like `import Foo.Bar as F` then it produces `F.X`.
+module Language.PureScript.Sugar.Names.Requalify
+  ( ReverseImports(..)
+  , buildReverseImports
+  , requalify
+  , requalifyConstraint
+  , reverseLookup
+  , requalifyTypesInErrors
+  ) where
+
+import Debug.Trace
+import Prelude
+import Control.Monad
+import qualified Data.Map as M
+import Data.Maybe
+import Data.Set (Set)
+import qualified Data.Set as Set
+import qualified Data.Text as T
+import qualified Language.PureScript.Constants.Prim as Prim
+import Language.PureScript.Errors
+import Language.PureScript.Names
+import Language.PureScript.Types
+import Language.PureScript.Sugar.Names.Env
+
+type ReverseImportMap a = M.Map (ModuleName, a) QualifiedBy
+
+-- | Like an Imports record, except this only contains type and type operator
+-- names, and is reversed - while an Imports record maps local names to fully
+-- qualified names, this data type maps fully qualified names to local names.
+-- This enables 'requalifying' qualified names with their locally qualified
+-- names if any, or no qualification if they were imported open
+data ReverseImports = ReverseImports
+  { reverseImportsTypes :: ReverseImportMap (ProperName 'TypeName)
+  , reverseImportsTypeOps :: ReverseImportMap (OpName 'TypeOpName)
+  , reverseImportsTypeClasses :: ReverseImportMap (ProperName 'ClassName)
+  }
+  deriving (Show)
+
+buildReverseImports :: Imports -> ReverseImports
+buildReverseImports (Imports { importedTypes, importedTypeOps, importedTypeClasses }) =
+  trace (show revimps) revimps
+  where
+  revimps = ReverseImports
+    { reverseImportsTypes =
+        M.fromListWith preferShortest $
+          mapMaybe (toReverseAssoc typeExceptions) $
+            M.toList importedTypes
+    , reverseImportsTypeOps =
+        M.fromListWith preferShortest $
+          mapMaybe (toReverseAssoc typeOpExceptions) $
+            M.toList importedTypeOps
+    , reverseImportsTypeClasses =
+        M.fromListWith preferShortest $
+          mapMaybe (toReverseAssoc typeClassExceptions) $
+            M.toList importedTypeClasses
+    }
+
+  preferShortest :: QualifiedBy -> QualifiedBy -> QualifiedBy
+  preferShortest x@(BySourcePos _) _ = x
+  preferShortest _ y@(BySourcePos _) = y
+  preferShortest (ByModuleName x) (ByModuleName y) = do
+    ByModuleName $
+      if T.length (runModuleName x) < T.length (runModuleName y)
+        then x
+        else y
+
+  -- | Given an entry from an ImportMap from an Imports (see Sugar.Names.Env)
+  -- which maps a local name to a fully qualified name, produce an entry for
+  -- the corresponding ReverseImports.
+  --
+  -- TODO does this need to care about situations where this is ambiguous i.e.
+  -- there are two different declarations that a given name could refer to? I
+  -- think the answer is yes. Eg:
+  --
+  -- import Foo as X
+  -- import Bar as X
+  --
+  -- is fine, as long as you don't do X.whatever for anything that both modules
+  -- export
+  --
+  -- We make exceptions for anything that has special cases in the type
+  -- pretty-printer such as Record and Function
+  toReverseAssoc :: Ord a => Set (Qualified a) -> (Qualified a, [ImportRecord a]) -> Maybe ((ModuleName, a), QualifiedBy)
+  toReverseAssoc exceptions (Qualified localModName name, importRecords) =
+    case importRecords of
+      [] ->
+        -- Probably shouldn't happen
+        Nothing
+      (ImportRecord { importName = importName@(Qualified mFullModName _) } : _) -> do
+        guard (not (Set.member importName exceptions))
+        -- TODO need to check the whole list including provenance? eg in the
+        -- case of two open imports with overlap and we're warning but it still
+        -- compiles
+        fullModName <- toMaybeModuleName mFullModName
+        pure ((fullModName, name), localModName)
+
+  typeExceptions :: Set (Qualified (ProperName 'TypeName))
+  typeExceptions = Set.fromList
+    [ Prim.Function
+    , Prim.Record
+    ]
+
+  typeOpExceptions :: Set (Qualified (OpName 'TypeOpName))
+  typeOpExceptions = Set.empty
+
+  typeClassExceptions :: Set (Qualified (ProperName 'ClassName))
+  typeClassExceptions = Set.fromList
+    [ Prim.Fail
+    , Prim.Partial
+    ]
+
+-- | This module provides functions for "re-qualifying" names in a type given
+-- an Imports record, so that they can be displayed unambiguously in
+-- diagnostics and suggestions without unnecessary qualification. That is,
+-- given a fully qualified name like `Foo.Bar.X`, this module lets you go to
+-- simply `X` (no qualification) if the given Imports record includes an open
+-- import for `X` from `Foo.Bar`, or alternatively if `Foo.Bar` is imported
+-- like `import Foo.Bar as F` then it produces `F.X`.
+requalify :: ReverseImports -> Type a -> Type a
+requalify revMap =
+  everywhereOnTypes $ \ty -> fromMaybe ty $ case ty of
+    TypeConstructor ann fullyQualifiedName ->
+      TypeConstructor ann
+        <$> reverseLookup (reverseImportsTypes revMap) fullyQualifiedName
+    TypeOp ann fullyQualifiedName -> do
+      TypeOp ann
+        <$> reverseLookup (reverseImportsTypeOps revMap) fullyQualifiedName
+    ConstrainedType ann fullyQualifiedConstraint ty' -> do
+      localConstraint <- reverseLookup (reverseImportsTypeClasses revMap) (constraintClass fullyQualifiedConstraint)
+      pure (ConstrainedType ann (fullyQualifiedConstraint { constraintClass = localConstraint }) ty')
+    _ ->
+      Nothing
+
+requalifyConstraint :: ReverseImports -> Constraint a -> Constraint a
+requalifyConstraint revMap fullyQualifiedConstraint =
+  fromMaybe fullyQualifiedConstraint $ do
+    localConstraint <- reverseLookup (reverseImportsTypeClasses revMap) (constraintClass fullyQualifiedConstraint)
+    pure $ fullyQualifiedConstraint
+      { constraintClass = localConstraint
+      , constraintKindArgs = requalify revMap <$> constraintKindArgs fullyQualifiedConstraint
+      , constraintArgs = requalify revMap <$> constraintArgs fullyQualifiedConstraint
+      }
+
+reverseLookup :: Show a => Ord a => ReverseImportMap a -> Qualified a -> Maybe (Qualified a)
+reverseLookup revMap (Qualified mFullModName name) = do
+  fullModName <- toMaybeModuleName mFullModName
+  mLocalModName <- M.lookup (fullModName, name) revMap
+  pure $ Qualified mLocalModName name
+
+
+-- | Convert fully qualified names in errors back to unqualified or locally
+-- qualified forms in certain hints and error messages, to make errors easier
+-- to understand and to avoid error messages like @Could not match type Query
+-- with type Query@.
+requalifyTypesInErrors :: Imports -> MultipleErrors -> MultipleErrors
+requalifyTypesInErrors imports =
+  onErrorMessages $ \e ->
+    case e of
+      ErrorMessage hints (NoInstanceFound con ambig unks) ->
+        ErrorMessage hints $ NoInstanceFound (requalifyConstraint revImports con) ambig unks
+      _ -> onTypesInErrorMessage requal e
+
+  where
+  revImports = buildReverseImports imports
+  requal = requalify revImports
+
+--   requalifyMessage =
+--     TypesDoNotUnify ty1 ty2 -> TypesDoNotUnify (requal ty1) (requal ty2)
+--     KindsDoNotUnify ty1 ty2 -> KindsDoNotUnify (requal ty1) (requal ty2)
+--     other -> other
+--
+--   requalifyHints = map $ \case
+--     ErrorUnifyingTypes ty1 ty2 ->
+--       ErrorUnifyingTypes (requal ty1) (requal ty2)
+--     ErrorInInstance clsName tys ->
+--       ErrorInInstance clsName (map requal tys)
+--     ErrorInSubsumption ty1 ty2 ->
+--       ErrorInSubsumption (requal ty1) (requal ty2)
+--     ErrorCheckingType expr ty ->
+--       ErrorCheckingType expr (requal ty)
+--     ErrorCheckingKind ty1 ty2 ->
+--       ErrorCheckingKind (requal ty1) (requal ty2)
+--     ErrorInferringKind ty ->
+--       ErrorInferringKind (requal ty)
+--     ErrorInApplication expr1 ty expr2 ->
+--       ErrorInApplication expr1 (requal ty) expr2
+--     other ->
+--       other
diff --git a/src/Language/PureScript/TypeChecker/Entailment/Coercible.hs b/src/Language/PureScript/TypeChecker/Entailment/Coercible.hs
index ab6a2338a2..f119d81dc6 100644
--- a/src/Language/PureScript/TypeChecker/Entailment/Coercible.hs
+++ b/src/Language/PureScript/TypeChecker/Entailment/Coercible.hs
@@ -598,7 +598,7 @@ canonRow a b
         (deriveds, (([], tail1), ([], tail2))) -> do
           pure . Canonicalized . S.fromList $ (tail1, tail2) : deriveds
         (_, (rl1, rl2)) ->
-          throwError . errorMessage $ TypesDoNotUnify (rowFromList rl1) (rowFromList rl2)
+          throwError . errorMessage $ mkTypesDoNotUnify (rowFromList rl1) (rowFromList rl2)
   | otherwise = empty
 
 -- | Unwraping a newtype can fails in two ways:
@@ -768,7 +768,7 @@ decompose env tyName axs bxs = do
           | ax == bx ->
               pure mempty
           | otherwise ->
-              throwError . errorMessage $ TypesDoNotUnify ax bx
+              throwError . errorMessage $ mkTypesDoNotUnify ax bx
         Representational ->
           pure $ S.singleton (ax, bx)
         Phantom ->
diff --git a/src/Language/PureScript/TypeChecker/Unify.hs b/src/Language/PureScript/TypeChecker/Unify.hs
index 38e181b365..6a5528cd45 100644
--- a/src/Language/PureScript/TypeChecker/Unify.hs
+++ b/src/Language/PureScript/TypeChecker/Unify.hs
@@ -130,7 +130,7 @@ unifyTypes t1 t2 = do
   unifyTypes' ty f@ForAll{} = f `unifyTypes` ty
   unifyTypes' (TypeVar _ v1) (TypeVar _ v2) | v1 == v2 = return ()
   unifyTypes' ty1@(TypeConstructor _ c1) ty2@(TypeConstructor _ c2) =
-    guardWith (errorMessage (TypesDoNotUnify ty1 ty2)) (c1 == c2)
+    guardWith (errorMessage (mkTypesDoNotUnify ty1 ty2)) (c1 == c2)
   unifyTypes' (TypeLevelString _ s1) (TypeLevelString _ s2) | s1 == s2 = return ()
   unifyTypes' (TypeLevelInt    _ n1) (TypeLevelInt    _ n2) | n1 == n2 = return ()
   unifyTypes' (TypeApp _ t3 t4) (TypeApp _ t5 t6) = do
@@ -154,7 +154,7 @@ unifyTypes t1 t2 = do
     throwError . errorMessage $ ConstrainedTypeUnified ty1 ty2
   unifyTypes' t3 t4@ConstrainedType{} = unifyTypes' t4 t3
   unifyTypes' t3 t4 =
-    throwError . errorMessage $ TypesDoNotUnify t3 t4
+    throwError . errorMessage $ mkTypesDoNotUnify t3 t4
 
 -- | Unify two rows, updating the current substitution
 --
@@ -177,7 +177,7 @@ unifyRows r1 r2 = sequence_ matches *> uncurry unifyTails rest where
     solveType u1 (rowFromList (sd2, rest'))
     solveType u2 (rowFromList (sd1, rest'))
   unifyTails _ _ =
-    throwError . errorMessage $ TypesDoNotUnify r1 r2
+    throwError . errorMessage $ mkTypesDoNotUnify r1 r2
 
 -- |
 -- Replace type wildcards with unknowns
diff --git a/tests/purs/failing/1175.out b/tests/purs/failing/1175.out
index 5d8ca2447e..76c3c5141d 100644
--- a/tests/purs/failing/1175.out
+++ b/tests/purs/failing/1175.out
@@ -6,10 +6,12 @@ at tests/purs/failing/1175.purs:11:11 - 11:12 (line 11, column 11 - line 11, col
        
     Int
        
+  (defined in module Prim)
   with type
           
     String
           
+  (defined in module Prim)
 
 while checking that type Int
   is at least as general as type String
@@ -17,6 +19,6 @@ while checking that expression 1
   has type String
 in value declaration f
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/1175.purs b/tests/purs/failing/1175.purs
index 13f1f703b9..f3a86ae542 100644
--- a/tests/purs/failing/1175.purs
+++ b/tests/purs/failing/1175.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module X where
 
 class Foo where
diff --git a/tests/purs/failing/1310.out b/tests/purs/failing/1310.out
index 4e558ad248..23404393b1 100644
--- a/tests/purs/failing/1310.out
+++ b/tests/purs/failing/1310.out
@@ -3,10 +3,10 @@ in module Issue1310
 at tests/purs/failing/1310.purs:18:8 - 18:31 (line 18, column 8 - line 18, column 31)
 
   No type class instance was found for
-                           
-    Issue1310.Inject Oops  
-                     Effect
-                           
+                 
+    Inject Oops  
+           Effect
+                 
 
 while applying a function inj
   of type Inject @t0 t1 t2 => t1 t3 -> t2 t3
diff --git a/tests/purs/failing/1570.out b/tests/purs/failing/1570.out
index 1b1a0fde57..5f429f21b7 100644
--- a/tests/purs/failing/1570.out
+++ b/tests/purs/failing/1570.out
@@ -8,9 +8,9 @@ at tests/purs/failing/1570.purs:6:10 - 6:16 (line 6, column 10 - line 6, column
     F
      
   having the kind
-                
-    Type -> Type
-                
+                          
+    Prim.Type -> Prim.Type
+                          
   instead.
 
 while inferring the type of \$0 ->      
diff --git a/tests/purs/failing/3275-BindingGroupErrorPos.out b/tests/purs/failing/3275-BindingGroupErrorPos.out
index 99207ba3b2..3c23c595aa 100644
--- a/tests/purs/failing/3275-BindingGroupErrorPos.out
+++ b/tests/purs/failing/3275-BindingGroupErrorPos.out
@@ -8,7 +8,7 @@ at tests/purs/failing/3275-BindingGroupErrorPos.purs:11:17 - 11:23 (line 11, col
         
   with kind
               
-    Type -> t3
+    Type -> t0
               
 
 while checking that type Result
diff --git a/tests/purs/failing/3275-DataBindingGroupErrorPos.out b/tests/purs/failing/3275-DataBindingGroupErrorPos.out
index 1039d74617..5488415337 100644
--- a/tests/purs/failing/3275-DataBindingGroupErrorPos.out
+++ b/tests/purs/failing/3275-DataBindingGroupErrorPos.out
@@ -7,9 +7,9 @@ at tests/purs/failing/3275-DataBindingGroupErrorPos.purs:7:19 - 7:22 (line 7, co
     Type
         
   with kind
-              
-    t10 -> t11
-              
+            
+    t0 -> t1
+            
 
 while checking that type Bar a
   has kind t0 -> t1
diff --git a/tests/purs/failing/3329.out b/tests/purs/failing/3329.out
index ce9bbe6c77..ad34cb45ad 100644
--- a/tests/purs/failing/3329.out
+++ b/tests/purs/failing/3329.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/3329.purs:24:8 - 24:11 (line 24, column 8 - line 24, column 11)
 
   No type class instance was found for
-                              
-    Main.Inject g0            
-                (Either f1 g0)
-                              
+                         
+    Inject g0            
+           (Either f1 g0)
+                         
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     Main.injectLeft
diff --git a/tests/purs/failing/3531-2.out b/tests/purs/failing/3531-2.out
index dcb39d4592..4bac28bf2e 100644
--- a/tests/purs/failing/3531-2.out
+++ b/tests/purs/failing/3531-2.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/3531-2.purs:22:11 - 22:22 (line 22, column 11 - line 22, column 22)
 
   No type class instance was found for
-                     
-    Main.C (X t2 Int)
-                     
+                
+    C (X t2 Int)
+                
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     Main.cx
diff --git a/tests/purs/failing/3531-3.out b/tests/purs/failing/3531-3.out
index 8f52a662cc..d0dae73681 100644
--- a/tests/purs/failing/3531-3.out
+++ b/tests/purs/failing/3531-3.out
@@ -3,15 +3,15 @@ in module Main
 at tests/purs/failing/3531-3.purs:22:11 - 22:22 (line 22, column 11 - line 22, column 22)
 
   No type class instance was found for
-                          
-    Main.C (X             
-              { foo :: Int
-              | t1        
-              }           
-              { foo :: Int
-              }           
-           )              
-                          
+                     
+    C (X             
+         { foo :: Int
+         | t1        
+         }           
+         { foo :: Int
+         }           
+      )              
+                     
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     Main.cx
diff --git a/tests/purs/failing/3531-4.out b/tests/purs/failing/3531-4.out
index 04b5b756d5..725a306d66 100644
--- a/tests/purs/failing/3531-4.out
+++ b/tests/purs/failing/3531-4.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/3531-4.purs:21:7 - 21:27 (line 21, column 7 - line 21, column 27)
 
   No type class instance was found for
-             
-    Main.C a4
-           b5
-             
+        
+    C a4
+      b5
+        
   The following instances partially overlap the above constraint, which means the rest of their instance chains will not be considered:
 
     Main.c1
diff --git a/tests/purs/failing/3531-5.out b/tests/purs/failing/3531-5.out
index f82fb0d6a1..660fc54e3e 100644
--- a/tests/purs/failing/3531-5.out
+++ b/tests/purs/failing/3531-5.out
@@ -3,13 +3,13 @@ in module Main
 at tests/purs/failing/3531-5.purs:16:7 - 16:27 (line 16, column 7 - line 16, column 27)
 
   No type class instance was found for
-             
-    Main.C a4
-           b5
-             
+        
+    C a4
+      b5
+        
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
-    instance in module Main with type forall a. C String (Array a) (line 9, column 1 - line 10, column 15)
+    instance in module Main with type forall a. Main.C Prim.String (Prim.Array a) (line 9, column 1 - line 10, column 15)
 
 
 while applying a function c
diff --git a/tests/purs/failing/3531-6.out b/tests/purs/failing/3531-6.out
index f454d0679e..faec02139f 100644
--- a/tests/purs/failing/3531-6.out
+++ b/tests/purs/failing/3531-6.out
@@ -3,14 +3,14 @@ in module Main
 at tests/purs/failing/3531-6.purs:21:7 - 21:27 (line 21, column 7 - line 21, column 27)
 
   No type class instance was found for
-             
-    Main.C a4
-           b5
-             
+        
+    C a4
+      b5
+        
   The following instances partially overlap the above constraint, which means the rest of their instance chains will not be considered:
 
-    instance in module Main with type forall a. C String (Array a) (line 9, column 1 - line 10, column 15)
-    instance in module Main with type C Int Int (line 14, column 1 - line 15, column 15)
+    instance in module Main with type forall a. Main.C Prim.String (Prim.Array a) (line 9, column 1 - line 10, column 15)
+    instance in module Main with type Main.C Prim.Int Prim.Int (line 14, column 1 - line 15, column 15)
 
 
 while applying a function c
diff --git a/tests/purs/failing/3531.out b/tests/purs/failing/3531.out
index 71e3f55972..d3b19a02c5 100644
--- a/tests/purs/failing/3531.out
+++ b/tests/purs/failing/3531.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/3531.purs:16:7 - 16:27 (line 16, column 7 - line 16, column 27)
 
   No type class instance was found for
-             
-    Main.C a2
-             
+        
+    C a2
+        
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     Main.c1
diff --git a/tests/purs/failing/3765-kinds.out b/tests/purs/failing/3765-kinds.out
index 138b69ba35..55531b60db 100644
--- a/tests/purs/failing/3765-kinds.out
+++ b/tests/purs/failing/3765-kinds.out
@@ -5,13 +5,13 @@ at tests/purs/failing/3765-kinds.purs:7:28 - 7:29 (line 7, column 28 - line 7, c
   Could not match kind
               
     ( a :: Int
-    | t11     
+    | t0      
     )         
               
   with kind
               
     ( b :: Int
-    | t11     
+    | t0      
     )         
               
 
diff --git a/tests/purs/failing/4024-2.out b/tests/purs/failing/4024-2.out
index af53a798d9..6fa44c2709 100644
--- a/tests/purs/failing/4024-2.out
+++ b/tests/purs/failing/4024-2.out
@@ -3,11 +3,11 @@ in module Main
 at tests/purs/failing/4024-2.purs:10:8 - 10:13 (line 10, column 8 - line 10, column 13)
 
   No type class instance was found for
-                   
-    Main.Foo t2    
-             t3    
-             String
-                   
+              
+    Foo t2    
+        t3    
+        String
+              
   The instance head contains unknown type variables. Consider adding a type annotation.
 
 while applying a function bar
diff --git a/tests/purs/failing/4024.out b/tests/purs/failing/4024.out
index 15184fe83e..07877fb218 100644
--- a/tests/purs/failing/4024.out
+++ b/tests/purs/failing/4024.out
@@ -3,11 +3,11 @@ in module Main
 at tests/purs/failing/4024.purs:10:8 - 10:13 (line 10, column 8 - line 10, column 13)
 
   No type class instance was found for
-                   
-    Main.Foo String
-             t2    
-             t3    
-                   
+              
+    Foo String
+        t2    
+        t3    
+              
 
 while applying a function bar
   of type Foo @Type @t0 @t1 String t2 t3 => Int -> String
diff --git a/tests/purs/failing/4028.out b/tests/purs/failing/4028.out
index 477c18364a..22f2ae5254 100644
--- a/tests/purs/failing/4028.out
+++ b/tests/purs/failing/4028.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/4028.purs:29:12 - 29:37 (line 29, column 12 - line 29, column 37)
 
   No type class instance was found for
-                      
-    Main.TLShow (S i2)
-                      
+                 
+    TLShow (S i2)
+                 
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     Main.tlShow2
diff --git a/tests/purs/failing/ArrayType.out b/tests/purs/failing/ArrayType.out
index 3c892bd842..9da9e9aa84 100644
--- a/tests/purs/failing/ArrayType.out
+++ b/tests/purs/failing/ArrayType.out
@@ -6,10 +6,12 @@ at tests/purs/failing/ArrayType.purs:10:7 - 10:8 (line 10, column 7 - line 10, c
        
     Int
        
+  (defined in module Prim)
   with type
           
     Number
           
+  (defined in module Prim)
 
 while checking that type Int
   is at least as general as type Number
@@ -17,6 +19,6 @@ while checking that expression x
   has type Number
 in value declaration foo
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/ArrayType.purs b/tests/purs/failing/ArrayType.purs
index 708fa5cdf4..86df70893e 100644
--- a/tests/purs/failing/ArrayType.purs
+++ b/tests/purs/failing/ArrayType.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 
 module Main where
 
diff --git a/tests/purs/failing/CoercibleHigherKindedData.out b/tests/purs/failing/CoercibleHigherKindedData.out
index afad7f895c..2550728cd7 100644
--- a/tests/purs/failing/CoercibleHigherKindedData.out
+++ b/tests/purs/failing/CoercibleHigherKindedData.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleHigherKindedData.purs:13:17 - 13:23 (line 13, column 17 - line 13, column 23)
 
   No type class instance was found for
-                                        
-    Prim.Coerce.Coercible (Unary t5)    
-                          (Binary a3 t5)
-                                        
+                                             
+    Prim.Coerce.Coercible (Main.Unary t5)    
+                          (Main.Binary a3 t5)
+                                             
   The instance head contains unknown type variables. Consider adding a type annotation.
 
 while solving type class constraint
diff --git a/tests/purs/failing/CoercibleHigherKindedNewtypes.out b/tests/purs/failing/CoercibleHigherKindedNewtypes.out
index 39c89d83dc..c997cefd6c 100644
--- a/tests/purs/failing/CoercibleHigherKindedNewtypes.out
+++ b/tests/purs/failing/CoercibleHigherKindedNewtypes.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleHigherKindedNewtypes.purs:13:8 - 13:14 (line 13, column 8 - line 13, column 14)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible Int   
-                          String
-                                
+                                     
+    Prim.Coerce.Coercible Prim.Int   
+                          Prim.String
+                                     
 
 while solving type class constraint
                                                       
diff --git a/tests/purs/failing/CoercibleKindMismatch.out b/tests/purs/failing/CoercibleKindMismatch.out
index 30ef9b17fc..41e5c172ed 100644
--- a/tests/purs/failing/CoercibleKindMismatch.out
+++ b/tests/purs/failing/CoercibleKindMismatch.out
@@ -7,9 +7,9 @@ at tests/purs/failing/CoercibleKindMismatch.purs:15:17 - 15:23 (line 15, column
     Type
         
   with kind
-               
-    t29 -> Type
-               
+              
+    t2 -> Type
+              
 
 while solving type class constraint
                                                                     
diff --git a/tests/purs/failing/CoercibleNominalTypeApp.out b/tests/purs/failing/CoercibleNominalTypeApp.out
index 2cc4b5a2a9..26c5e27fec 100644
--- a/tests/purs/failing/CoercibleNominalTypeApp.out
+++ b/tests/purs/failing/CoercibleNominalTypeApp.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CoercibleNominalTypeApp.purs:13:8 - 13:14 (line 13, column
        
     Int
        
+  (defined in module Prim)
   with type
           
     String
           
+  (defined in module Prim)
 
 while solving type class constraint
                                               
@@ -22,6 +24,6 @@ while checking that expression coerce
   has type G @Type Maybe Int -> G @Type Maybe String
 in value declaration gToG
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CoercibleNominalTypeApp.purs b/tests/purs/failing/CoercibleNominalTypeApp.purs
index 80112d2c8e..0087fedb9c 100644
--- a/tests/purs/failing/CoercibleNominalTypeApp.purs
+++ b/tests/purs/failing/CoercibleNominalTypeApp.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Safe.Coerce (coerce)
diff --git a/tests/purs/failing/CoercibleNonCanonical1.out b/tests/purs/failing/CoercibleNonCanonical1.out
index 80405754e0..93bfdee622 100644
--- a/tests/purs/failing/CoercibleNonCanonical1.out
+++ b/tests/purs/failing/CoercibleNonCanonical1.out
@@ -3,16 +3,11 @@ in module Main
 at tests/purs/failing/CoercibleNonCanonical1.purs:11:27 - 11:33 (line 11, column 27 - line 11, column 33)
 
   No type class instance was found for
-                                    
-    Prim.Coerce.Coercible a0        
-                          (D (N a0))
-                                    
+                        
+    Coercible a0        
+              (D (N a0))
+                        
 
-while solving type class constraint
-                                    
-  Prim.Coerce.Coercible a0          
-                        (N @Type a0)
-                                    
 while checking that type forall (a :: Type) (b :: Type). Coercible @Type a b => a -> b
   is at least as general as type a0 -> N @Type a0
 while checking that expression coerce
diff --git a/tests/purs/failing/CoercibleNonCanonical2.out b/tests/purs/failing/CoercibleNonCanonical2.out
index b1bb270ff2..6d963627e1 100644
--- a/tests/purs/failing/CoercibleNonCanonical2.out
+++ b/tests/purs/failing/CoercibleNonCanonical2.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleNonCanonical2.purs:10:27 - 10:33 (line 10, column 27 - line 10, column 33)
 
   No type class instance was found for
-                            
-    Prim.Coerce.Coercible a0
-                          b1
-                            
+                
+    Coercible a0
+              b1
+                
 
 while checking that type forall (a :: Type) (b :: Type). Coercible @Type a b => a -> b
   is at least as general as type a0 -> b1
diff --git a/tests/purs/failing/CoercibleRepresentational2.out b/tests/purs/failing/CoercibleRepresentational2.out
index 435c8421cc..1d3556478d 100644
--- a/tests/purs/failing/CoercibleRepresentational2.out
+++ b/tests/purs/failing/CoercibleRepresentational2.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational2.purs:9:14 - 9:20 (line 9, column 14 - line 9, column 20)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible Int   
-                          String
-                                
+                                     
+    Prim.Coerce.Coercible Prim.Int   
+                          Prim.String
+                                     
 
 while solving type class constraint
                                      
diff --git a/tests/purs/failing/CoercibleRepresentational3.out b/tests/purs/failing/CoercibleRepresentational3.out
index f718b3c4cb..fe665bf9e3 100644
--- a/tests/purs/failing/CoercibleRepresentational3.out
+++ b/tests/purs/failing/CoercibleRepresentational3.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational3.purs:9:14 - 9:20 (line 9, column 14 - line 9, column 20)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible Int   
-                          String
-                                
+                                     
+    Prim.Coerce.Coercible Prim.Int   
+                          Prim.String
+                                     
 
 while solving type class constraint
                                      
diff --git a/tests/purs/failing/CoercibleRepresentational4.out b/tests/purs/failing/CoercibleRepresentational4.out
index 50d61e5c8b..71d50d6e7a 100644
--- a/tests/purs/failing/CoercibleRepresentational4.out
+++ b/tests/purs/failing/CoercibleRepresentational4.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational4.purs:11:38 - 11:44 (line 11, column 38 - line 11, column 44)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible Int   
-                          String
-                                
+                                     
+    Prim.Coerce.Coercible Prim.Int   
+                          Prim.String
+                                     
 
 while solving type class constraint
                                                  
diff --git a/tests/purs/failing/CoercibleRepresentational5.out b/tests/purs/failing/CoercibleRepresentational5.out
index 6c215721cf..afe78f2599 100644
--- a/tests/purs/failing/CoercibleRepresentational5.out
+++ b/tests/purs/failing/CoercibleRepresentational5.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational5.purs:15:38 - 15:44 (line 15, column 38 - line 15, column 44)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible Int   
-                          String
-                                
+                                     
+    Prim.Coerce.Coercible Prim.Int   
+                          Prim.String
+                                     
 
 while solving type class constraint
                                                                    
diff --git a/tests/purs/failing/CoercibleRepresentational6.out b/tests/purs/failing/CoercibleRepresentational6.out
index a587159c40..14f549a356 100644
--- a/tests/purs/failing/CoercibleRepresentational6.out
+++ b/tests/purs/failing/CoercibleRepresentational6.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational6.purs:8:10 - 8:16 (line 8, column 10 - line 8, column 16)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible (N a0)
-                          a0    
-                                
+                                  
+    Prim.Coerce.Coercible (N.N a0)
+                          a0      
+                                  
 
   Solving this instance requires the newtype constructor N to be in scope.
 
diff --git a/tests/purs/failing/CoercibleRepresentational7.out b/tests/purs/failing/CoercibleRepresentational7.out
index 0c5c1005a5..8088b7ec40 100644
--- a/tests/purs/failing/CoercibleRepresentational7.out
+++ b/tests/purs/failing/CoercibleRepresentational7.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational7.purs:8:10 - 8:16 (line 8, column 10 - line 8, column 16)
 
   No type class instance was found for
-                                
-    Prim.Coerce.Coercible (N a0)
-                          a0    
-                                
+                                  
+    Prim.Coerce.Coercible (N.N a0)
+                          a0      
+                                  
 
   Solving this instance requires the newtype constructor N to be in scope.
 
diff --git a/tests/purs/failing/CoercibleRepresentational8.out b/tests/purs/failing/CoercibleRepresentational8.out
index cb5275fcbf..e3800ebc7b 100644
--- a/tests/purs/failing/CoercibleRepresentational8.out
+++ b/tests/purs/failing/CoercibleRepresentational8.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/failing/CoercibleRepresentational8.purs:9:16 - 9:22 (line 9, column 16 - line 9, column 22)
 
   No type class instance was found for
-                            
-    Prim.Coerce.Coercible a0
-                          b1
-                            
+                
+    Coercible a0
+              b1
+                
 
 while checking that type forall (a :: Type) (b :: Type). Coercible @Type a b => a -> b
   is at least as general as type a0 -> b1
diff --git a/tests/purs/failing/CompareInt1.out b/tests/purs/failing/CompareInt1.out
index 452403b8b6..1b1c069140 100644
--- a/tests/purs/failing/CompareInt1.out
+++ b/tests/purs/failing/CompareInt1.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt1.purs:14:16 - 14:29 (line 14, column 16 - line
       
     EQ
       
+  (defined in module Prim.Ordering)
   with type
       
     GT
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a0 is a rigid type variable
       b1 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt1.purs b/tests/purs/failing/CompareInt1.purs
index d53a28c5f7..763b430ddc 100644
--- a/tests/purs/failing/CompareInt1.purs
+++ b/tests/purs/failing/CompareInt1.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt10.out b/tests/purs/failing/CompareInt10.out
index 35b30cb145..c760dd9820 100644
--- a/tests/purs/failing/CompareInt10.out
+++ b/tests/purs/failing/CompareInt10.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt10.purs:14:16 - 14:27 (line 14, column 16 - line
       
     LT
       
+  (defined in module Prim.Ordering)
   with type
       
     EQ
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a1 is a rigid type variable
       c0 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt10.purs b/tests/purs/failing/CompareInt10.purs
index fef893fbcf..41259d66a6 100644
--- a/tests/purs/failing/CompareInt10.purs
+++ b/tests/purs/failing/CompareInt10.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt11.out b/tests/purs/failing/CompareInt11.out
index 930710c038..8bf96b6e4f 100644
--- a/tests/purs/failing/CompareInt11.out
+++ b/tests/purs/failing/CompareInt11.out
@@ -3,11 +3,11 @@ in module Main
 at tests/purs/failing/CompareInt11.purs:14:14 - 14:26 (line 14, column 14 - line 14, column 26)
 
   No type class instance was found for
-                       
-    Prim.Int.Compare a0
-                     5 
-                     LT
-                       
+              
+    Compare a0
+            5 
+            LT
+              
 
 while checking that type forall (l :: Int) (r :: Int).       
                            Compare l r LT => Proxy @(Row Int)
diff --git a/tests/purs/failing/CompareInt12.out b/tests/purs/failing/CompareInt12.out
index 8a56b46db2..08ac3ad113 100644
--- a/tests/purs/failing/CompareInt12.out
+++ b/tests/purs/failing/CompareInt12.out
@@ -3,11 +3,11 @@ in module Main
 at tests/purs/failing/CompareInt12.purs:14:14 - 14:27 (line 14, column 14 - line 14, column 27)
 
   No type class instance was found for
-                       
-    Prim.Int.Compare a0
-                     20
-                     GT
-                       
+              
+    Compare a0
+            20
+            GT
+              
 
 while checking that type forall (l :: Int) (r :: Int).       
                            Compare l r GT => Proxy @(Row Int)
diff --git a/tests/purs/failing/CompareInt2.out b/tests/purs/failing/CompareInt2.out
index 8817b303d9..5efa78fd30 100644
--- a/tests/purs/failing/CompareInt2.out
+++ b/tests/purs/failing/CompareInt2.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt2.purs:14:14 - 14:27 (line 14, column 14 - line
       
     LT
       
+  (defined in module Prim.Ordering)
   with type
       
     GT
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a1 is a rigid type variable
       b0 is a rigid type variable
         bound at (line 14, column 14 - line 14, column 27)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt2.purs b/tests/purs/failing/CompareInt2.purs
index 06ba919f83..e8ac291afa 100644
--- a/tests/purs/failing/CompareInt2.purs
+++ b/tests/purs/failing/CompareInt2.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt3.out b/tests/purs/failing/CompareInt3.out
index 35c8a1d0da..90ae237a66 100644
--- a/tests/purs/failing/CompareInt3.out
+++ b/tests/purs/failing/CompareInt3.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt3.purs:14:16 - 14:28 (line 14, column 16 - line
       
     EQ
       
+  (defined in module Prim.Ordering)
   with type
       
     LT
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a0 is a rigid type variable
       b1 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt3.purs b/tests/purs/failing/CompareInt3.purs
index 93bc00b8c2..89ea3f00cd 100644
--- a/tests/purs/failing/CompareInt3.purs
+++ b/tests/purs/failing/CompareInt3.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt4.out b/tests/purs/failing/CompareInt4.out
index d2c7f2956d..4cd43583e7 100644
--- a/tests/purs/failing/CompareInt4.out
+++ b/tests/purs/failing/CompareInt4.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt4.purs:14:14 - 14:26 (line 14, column 14 - line
       
     GT
       
+  (defined in module Prim.Ordering)
   with type
       
     LT
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a1 is a rigid type variable
       b0 is a rigid type variable
         bound at (line 14, column 14 - line 14, column 26)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt4.purs b/tests/purs/failing/CompareInt4.purs
index fca2e6d42a..b33aca1aeb 100644
--- a/tests/purs/failing/CompareInt4.purs
+++ b/tests/purs/failing/CompareInt4.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt5.out b/tests/purs/failing/CompareInt5.out
index a7e90314c4..c6c8e801e8 100644
--- a/tests/purs/failing/CompareInt5.out
+++ b/tests/purs/failing/CompareInt5.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt5.purs:14:16 - 14:29 (line 14, column 16 - line
       
     LT
       
+  (defined in module Prim.Ordering)
   with type
       
     GT
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a1 is a rigid type variable
       c0 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt5.purs b/tests/purs/failing/CompareInt5.purs
index f4f8fba8a8..8350453d53 100644
--- a/tests/purs/failing/CompareInt5.purs
+++ b/tests/purs/failing/CompareInt5.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt6.out b/tests/purs/failing/CompareInt6.out
index a355c5dba3..87a70f63ee 100644
--- a/tests/purs/failing/CompareInt6.out
+++ b/tests/purs/failing/CompareInt6.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt6.purs:14:16 - 14:28 (line 14, column 16 - line
       
     GT
       
+  (defined in module Prim.Ordering)
   with type
       
     LT
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a1 is a rigid type variable
       c0 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt6.purs b/tests/purs/failing/CompareInt6.purs
index d9ba79f870..a773fd2dff 100644
--- a/tests/purs/failing/CompareInt6.purs
+++ b/tests/purs/failing/CompareInt6.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt7.out b/tests/purs/failing/CompareInt7.out
index f065e86703..983321af1e 100644
--- a/tests/purs/failing/CompareInt7.out
+++ b/tests/purs/failing/CompareInt7.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt7.purs:14:16 - 14:27 (line 14, column 16 - line
       
     LT
       
+  (defined in module Prim.Ordering)
   with type
       
     EQ
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a0 is a rigid type variable
       c1 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt7.purs b/tests/purs/failing/CompareInt7.purs
index 2155a911d2..bdbca20d9e 100644
--- a/tests/purs/failing/CompareInt7.purs
+++ b/tests/purs/failing/CompareInt7.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt8.out b/tests/purs/failing/CompareInt8.out
index e7c4cbd1d0..3e3263a4b7 100644
--- a/tests/purs/failing/CompareInt8.out
+++ b/tests/purs/failing/CompareInt8.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt8.purs:14:16 - 14:27 (line 14, column 16 - line
       
     GT
       
+  (defined in module Prim.Ordering)
   with type
       
     EQ
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a0 is a rigid type variable
       c1 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt8.purs b/tests/purs/failing/CompareInt8.purs
index 85bf481870..7134061370 100644
--- a/tests/purs/failing/CompareInt8.purs
+++ b/tests/purs/failing/CompareInt8.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/CompareInt9.out b/tests/purs/failing/CompareInt9.out
index 9e55dcf883..0b2429203c 100644
--- a/tests/purs/failing/CompareInt9.out
+++ b/tests/purs/failing/CompareInt9.out
@@ -6,10 +6,12 @@ at tests/purs/failing/CompareInt9.purs:14:16 - 14:27 (line 14, column 16 - line
       
     GT
       
+  (defined in module Prim.Ordering)
   with type
       
     EQ
       
+  (defined in module Prim.Ordering)
 
 while solving type class constraint
                      
@@ -38,6 +40,6 @@ where a1 is a rigid type variable
       c0 is a rigid type variable
         bound at (line 0, column 0 - line 0, column 0)
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/CompareInt9.purs b/tests/purs/failing/CompareInt9.purs
index 21743243b2..10dbd2138c 100644
--- a/tests/purs/failing/CompareInt9.purs
+++ b/tests/purs/failing/CompareInt9.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prim.Int (class Compare)
diff --git a/tests/purs/failing/ConstraintFailure.out b/tests/purs/failing/ConstraintFailure.out
index 17d2c94bad..fd159d3e6a 100644
--- a/tests/purs/failing/ConstraintFailure.out
+++ b/tests/purs/failing/ConstraintFailure.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/ConstraintFailure.purs:12:8 - 12:12 (line 12, column 8 - line 12, column 12)
 
   No type class instance was found for
-                      
-    Data.Show.Show Foo
-                      
+                           
+    Data.Show.Show Main.Foo
+                           
 
 while checking that type forall (a :: Type). Show a => a -> String
   is at least as general as type t0 t1 t2
diff --git a/tests/purs/failing/DiffKindsSameName.out b/tests/purs/failing/DiffKindsSameName.out
index 13f180f524..6f7803b6de 100644
--- a/tests/purs/failing/DiffKindsSameName.out
+++ b/tests/purs/failing/DiffKindsSameName.out
@@ -3,13 +3,13 @@ in module DiffKindsSameName
 at tests/purs/failing/DiffKindsSameName.purs:13:18 - 13:31 (line 13, column 18 - line 13, column 31)
 
   Could not match kind
-            
-    DemoKind
-            
+                 
+    LibB.DemoKind
+                 
   with kind
-            
-    DemoKind
-            
+                 
+    LibA.DemoKind
+                 
 
 while checking that type DemoData
   has kind DemoKind
diff --git a/tests/purs/failing/DoNotSuggestComposition2.out b/tests/purs/failing/DoNotSuggestComposition2.out
index 5126c8a650..986b025070 100644
--- a/tests/purs/failing/DoNotSuggestComposition2.out
+++ b/tests/purs/failing/DoNotSuggestComposition2.out
@@ -3,13 +3,13 @@ in module DoNotSuggestComposition2
 at tests/purs/failing/DoNotSuggestComposition2.purs:7:27 - 7:30 (line 7, column 27 - line 7, column 30)
 
   Could not match type
-          
-    Record
-          
+               
+    Prim.Record
+               
   with type
-                
-    Function Int
-                
+                     
+    Prim.Function Int
+                     
 
 while trying to match type { y :: Int
                            }         
diff --git a/tests/purs/failing/FoldableInstance4.out b/tests/purs/failing/FoldableInstance4.out
index 4e53669e6b..ee84c4237a 100644
--- a/tests/purs/failing/FoldableInstance4.out
+++ b/tests/purs/failing/FoldableInstance4.out
@@ -3,9 +3,9 @@ in module FoldableInstance4
 at tests/purs/failing/FoldableInstance4.purs:8:1 - 8:27 (line 8, column 1 - line 8, column 27)
 
   No type class instance was found for
-                                        
-    Data.Foldable.Foldable (Function t3)
-                                        
+                               
+    Foldable (Prim.Function t3)
+                               
   The instance head contains unknown type variables. Consider adding a type annotation.
 
 while applying a function foldl
diff --git a/tests/purs/failing/InfiniteKind2.out b/tests/purs/failing/InfiniteKind2.out
index c06581ce76..214a7c65e2 100644
--- a/tests/purs/failing/InfiniteKind2.out
+++ b/tests/purs/failing/InfiniteKind2.out
@@ -3,9 +3,9 @@ in module InfiniteKind2
 at tests/purs/failing/InfiniteKind2.purs:5:23 - 5:27 (line 5, column 23 - line 5, column 27)
 
   An infinite kind was inferred for a type:
-                      
-    (t5 -> t6) -> Type
-                      
+                           
+    (t5 -> t6) -> Prim.Type
+                           
 
 while checking that type Tree
   has kind t0
diff --git a/tests/purs/failing/InstanceChainBothUnknownAndMatch.out b/tests/purs/failing/InstanceChainBothUnknownAndMatch.out
index a097d1936c..cfd530ae67 100644
--- a/tests/purs/failing/InstanceChainBothUnknownAndMatch.out
+++ b/tests/purs/failing/InstanceChainBothUnknownAndMatch.out
@@ -3,19 +3,19 @@ in module InstanceChains.BothUnknownAndMatch
 at tests/purs/failing/InstanceChainBothUnknownAndMatch.purs:15:13 - 15:53 (line 15, column 13 - line 15, column 53)
 
   No type class instance was found for
-                                                         
-    InstanceChains.BothUnknownAndMatch.Same (Proxy       
-                                               ( m :: Int
-                                               , u :: t3 
-                                               )         
-                                            )            
-                                            (Proxy       
-                                               ( m :: Int
-                                               , u :: Int
-                                               )         
-                                            )            
-                                            t4           
-                                                         
+                      
+    Same (Proxy       
+            ( m :: Int
+            , u :: t3 
+            )         
+         )            
+         (Proxy       
+            ( m :: Int
+            , u :: Int
+            )         
+         )            
+         t4           
+                      
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     InstanceChains.BothUnknownAndMatch.sameY
diff --git a/tests/purs/failing/InstanceChainSkolemUnknownMatch.out b/tests/purs/failing/InstanceChainSkolemUnknownMatch.out
index 82e1ace510..67c5e4cc46 100644
--- a/tests/purs/failing/InstanceChainSkolemUnknownMatch.out
+++ b/tests/purs/failing/InstanceChainSkolemUnknownMatch.out
@@ -3,11 +3,11 @@ in module InstanceChainSkolemUnknownMatch
 at tests/purs/failing/InstanceChainSkolemUnknownMatch.purs:13:13 - 13:36 (line 13, column 13 - line 13, column 36)
 
   No type class instance was found for
-                                                    
-    InstanceChainSkolemUnknownMatch.Same (Proxy t3) 
-                                         (Proxy Int)
-                                         t4         
-                                                    
+                    
+    Same (Proxy t3) 
+         (Proxy Int)
+         t4         
+                    
   The following instance partially overlaps the above constraint, which means the rest of its instance chain will not be considered:
 
     InstanceChainSkolemUnknownMatch.sameY
diff --git a/tests/purs/failing/InstanceSigsBodyIncorrect.out b/tests/purs/failing/InstanceSigsBodyIncorrect.out
index d29e6cddbc..b585689db4 100644
--- a/tests/purs/failing/InstanceSigsBodyIncorrect.out
+++ b/tests/purs/failing/InstanceSigsBodyIncorrect.out
@@ -6,10 +6,12 @@ at tests/purs/failing/InstanceSigsBodyIncorrect.purs:10:9 - 10:13 (line 10, colu
            
     Boolean
            
+  (defined in module Prim)
   with type
           
     Number
           
+  (defined in module Prim)
 
 while checking that type Boolean
   is at least as general as type Number
@@ -17,6 +19,6 @@ while checking that expression true
   has type Number
 in value declaration fooNumber
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/InstanceSigsBodyIncorrect.purs b/tests/purs/failing/InstanceSigsBodyIncorrect.purs
index fd3c4370d5..023c9feeff 100644
--- a/tests/purs/failing/InstanceSigsBodyIncorrect.purs
+++ b/tests/purs/failing/InstanceSigsBodyIncorrect.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 
 module Main where
 
diff --git a/tests/purs/failing/InstanceSigsDifferentTypes.out b/tests/purs/failing/InstanceSigsDifferentTypes.out
index f06904a946..8a551c60ec 100644
--- a/tests/purs/failing/InstanceSigsDifferentTypes.out
+++ b/tests/purs/failing/InstanceSigsDifferentTypes.out
@@ -6,10 +6,12 @@ at tests/purs/failing/InstanceSigsDifferentTypes.purs:10:9 - 10:12 (line 10, col
           
     Number
           
+  (defined in module Prim)
   with type
        
     Int
        
+  (defined in module Prim)
 
 while checking that type Number
   is at least as general as type Int
@@ -17,6 +19,6 @@ while checking that expression 0.0
   has type Int
 in value declaration fooNumber
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/InstanceSigsDifferentTypes.purs b/tests/purs/failing/InstanceSigsDifferentTypes.purs
index 0de2109d4d..19af12ab4e 100644
--- a/tests/purs/failing/InstanceSigsDifferentTypes.purs
+++ b/tests/purs/failing/InstanceSigsDifferentTypes.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 
 module Main where
 
diff --git a/tests/purs/failing/InstanceSigsIncorrectType.out b/tests/purs/failing/InstanceSigsIncorrectType.out
index c8779b4aab..3292c4ce69 100644
--- a/tests/purs/failing/InstanceSigsIncorrectType.out
+++ b/tests/purs/failing/InstanceSigsIncorrectType.out
@@ -6,10 +6,12 @@ at tests/purs/failing/InstanceSigsIncorrectType.purs:8:1 - 10:13 (line 8, column
            
     Boolean
            
+  (defined in module Prim)
   with type
           
     Number
           
+  (defined in module Prim)
 
 while trying to match type Foo$Dict t0
   with type Foo$Dict Number
@@ -20,6 +22,6 @@ in value declaration fooNumber
 
 where t0 is an unknown type
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/InstanceSigsIncorrectType.purs b/tests/purs/failing/InstanceSigsIncorrectType.purs
index f452f2ebb8..42a683dc30 100644
--- a/tests/purs/failing/InstanceSigsIncorrectType.purs
+++ b/tests/purs/failing/InstanceSigsIncorrectType.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 
 module Main where
 
diff --git a/tests/purs/failing/InvalidCoercibleInstanceDeclaration.out b/tests/purs/failing/InvalidCoercibleInstanceDeclaration.out
index 34e8147142..7ae0a6d26b 100644
--- a/tests/purs/failing/InvalidCoercibleInstanceDeclaration.out
+++ b/tests/purs/failing/InvalidCoercibleInstanceDeclaration.out
@@ -2,10 +2,10 @@ Error found:
 at tests/purs/failing/InvalidCoercibleInstanceDeclaration.purs:8:1 - 8:36 (line 8, column 1 - line 8, column 36)
 
   Invalid type class instance declaration for
-                           
-    Prim.Coerce.Coercible D
-                          D
-                           
+                                
+    Prim.Coerce.Coercible Main.D
+                          Main.D
+                                
   Instance declarations of this type class are disallowed.
 
 
diff --git a/tests/purs/failing/KindError.out b/tests/purs/failing/KindError.out
index fe56bd3e06..2603bdece1 100644
--- a/tests/purs/failing/KindError.out
+++ b/tests/purs/failing/KindError.out
@@ -8,7 +8,7 @@ at tests/purs/failing/KindError.purs:6:35 - 6:36 (line 6, column 35 - line 6, co
         
   with kind
             
-    t8 -> t9
+    t0 -> t1
             
 
 while checking that type f
diff --git a/tests/purs/failing/KindStar.out b/tests/purs/failing/KindStar.out
index 03dc0acb69..81f9491be5 100644
--- a/tests/purs/failing/KindStar.out
+++ b/tests/purs/failing/KindStar.out
@@ -8,9 +8,9 @@ at tests/purs/failing/KindStar.purs:7:1 - 7:13 (line 7, column 1 - line 7, colum
     List
         
   having the kind
-                
-    Type -> Type
-                
+                          
+    Prim.Type -> Prim.Type
+                          
   instead.
 
 in value declaration test
diff --git a/tests/purs/failing/LacksWithSubGoal.out b/tests/purs/failing/LacksWithSubGoal.out
index 4938a23c86..fd7d150bb9 100644
--- a/tests/purs/failing/LacksWithSubGoal.out
+++ b/tests/purs/failing/LacksWithSubGoal.out
@@ -3,10 +3,10 @@ in module LacksWithSubGoal
 at tests/purs/failing/LacksWithSubGoal.purs:14:11 - 14:33 (line 14, column 11 - line 14, column 33)
 
   No type class instance was found for
-                          
-    Prim.Row.Lacks "hello"
-                   r0     
-                          
+                 
+    Lacks "hello"
+          r0     
+                 
 
 while solving type class constraint
                            
diff --git a/tests/purs/failing/MissingClassMember.out b/tests/purs/failing/MissingClassMember.out
index fcbd3dcf19..ab75861e5f 100644
--- a/tests/purs/failing/MissingClassMember.out
+++ b/tests/purs/failing/MissingClassMember.out
@@ -2,8 +2,8 @@ Error found:
 at tests/purs/failing/MissingClassMember.purs:9:1 - 10:10 (line 9, column 1 - line 10, column 10)
 
   The following type class members have not been implemented:
-  b :: String -> Number
-  c :: forall f. String -> f String
+  b :: Prim.String -> Prim.Number
+  c :: forall f. Prim.String -> f Prim.String
 
 in type class instance
                
diff --git a/tests/purs/failing/MultipleErrors.out b/tests/purs/failing/MultipleErrors.out
index b33b1ad362..3698a0150e 100644
--- a/tests/purs/failing/MultipleErrors.out
+++ b/tests/purs/failing/MultipleErrors.out
@@ -7,10 +7,12 @@ Error 1 of 2:
             
       String
             
+    (defined in module Prim)
     with type
          
       Int
          
+    (defined in module Prim)
 
   while checking that type String
     is at least as general as type Int
@@ -18,7 +20,7 @@ Error 1 of 2:
     has type Int
   in binding group foo, bar
 
-  See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+  See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
   or to contribute content related to this error.
 
 Error 2 of 2:
@@ -30,10 +32,12 @@ Error 2 of 2:
             
       String
             
+    (defined in module Prim)
     with type
          
       Int
          
+    (defined in module Prim)
 
   while checking that type String
     is at least as general as type Int
@@ -41,6 +45,6 @@ Error 2 of 2:
     has type Int
   in binding group foo, bar
 
-  See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+  See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
   or to contribute content related to this error.
 
diff --git a/tests/purs/failing/MultipleErrors.purs b/tests/purs/failing/MultipleErrors.purs
index b1d8a8cacd..ae31b19b52 100644
--- a/tests/purs/failing/MultipleErrors.purs
+++ b/tests/purs/failing/MultipleErrors.purs
@@ -1,5 +1,5 @@
--- @shouldFailWith TypesDoNotUnify
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module MultipleErrors where
 
 import Prelude
diff --git a/tests/purs/failing/OverlapAcrossModulesUnnamedInstance.out b/tests/purs/failing/OverlapAcrossModulesUnnamedInstance.out
index 9ea61e29b4..e2936cbc25 100644
--- a/tests/purs/failing/OverlapAcrossModulesUnnamedInstance.out
+++ b/tests/purs/failing/OverlapAcrossModulesUnnamedInstance.out
@@ -10,7 +10,7 @@ at tests/purs/failing/OverlapAcrossModulesUnnamedInstance.purs:6:1 - 6:15 (line
   The following instances were found:
 
     OverlapAcrossModules.X.cX
-    instance in module OverlapAcrossModules with type C X Y (line 6, column 1 - line 6, column 15)
+    instance in module OverlapAcrossModules with type OverlapAcrossModules.Class.C X Y (line 6, column 1 - line 6, column 15)
 
 
 in type class instance
diff --git a/tests/purs/failing/OverlappingUnnamedInstances.out b/tests/purs/failing/OverlappingUnnamedInstances.out
index 22f0525f1c..629e174bef 100644
--- a/tests/purs/failing/OverlappingUnnamedInstances.out
+++ b/tests/purs/failing/OverlappingUnnamedInstances.out
@@ -8,8 +8,8 @@ at tests/purs/failing/OverlappingUnnamedInstances.purs:10:1 - 11:13 (line 10, co
                  
   The following instances were found:
 
-    instance in module Main with type forall a. Test a (line 7, column 1 - line 8, column 13)
-    instance in module Main with type Test Int (line 10, column 1 - line 11, column 13)
+    instance in module Main with type forall a. Main.Test a (line 7, column 1 - line 8, column 13)
+    instance in module Main with type Main.Test Int (line 10, column 1 - line 11, column 13)
 
 
 in type class instance
diff --git a/tests/purs/failing/OverlappingVars.out b/tests/purs/failing/OverlappingVars.out
index 8f49802299..95b7d37342 100644
--- a/tests/purs/failing/OverlappingVars.out
+++ b/tests/purs/failing/OverlappingVars.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/OverlappingVars.purs:14:8 - 14:20 (line 14, column 8 - line 14, column 20)
 
   No type class instance was found for
-                                         
-    Main.OverlappingVars (Foo String Int)
-                                         
+                                    
+    OverlappingVars (Foo String Int)
+                                    
 
 while applying a function f
   of type OverlappingVars t0 => t0 -> t0
diff --git a/tests/purs/failing/PolykindUnnamedInstanceOverlapping.out b/tests/purs/failing/PolykindUnnamedInstanceOverlapping.out
index 5e84fbb8e9..fcf987f1df 100644
--- a/tests/purs/failing/PolykindUnnamedInstanceOverlapping.out
+++ b/tests/purs/failing/PolykindUnnamedInstanceOverlapping.out
@@ -8,8 +8,8 @@ at tests/purs/failing/PolykindUnnamedInstanceOverlapping.purs:12:1 - 13:19 (line
                         
   The following instances were found:
 
-    instance in module Main with type forall a. ShowP (Proxy a) (line 9, column 1 - line 10, column 19)
-    instance in module Main with type forall a. ShowP (Proxy a) (line 12, column 1 - line 13, column 19)
+    instance in module Main with type forall a. Main.ShowP (Proxy a) (line 9, column 1 - line 10, column 19)
+    instance in module Main with type forall a. Main.ShowP (Proxy a) (line 12, column 1 - line 13, column 19)
 
 
 in type class instance
diff --git a/tests/purs/failing/QualifiedErrorsUnification.out b/tests/purs/failing/QualifiedErrorsUnification.out
new file mode 100644
index 0000000000..a0814bd7eb
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnification.out
@@ -0,0 +1,26 @@
+Error found:
+in module Main
+at tests/purs/failing/QualifiedErrorsUnification.purs:9:15 - 9:18 (line 9, column 15 - line 9, column 18)
+
+  Could not match type
+                             
+    Data.List.Lazy.Types.List
+                             
+  (defined in module Data.List.Lazy.Types)
+  with type
+        
+    List
+        
+  (defined in module Data.List.Types)
+
+while trying to match type List t0
+  with type List Unit
+while checking that expression nil
+  has type List Unit
+in value declaration wrongModule
+
+where t0 is an unknown type
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/QualifiedErrorsUnification.purs b/tests/purs/failing/QualifiedErrorsUnification.purs
new file mode 100644
index 0000000000..3d106d9ba9
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnification.purs
@@ -0,0 +1,9 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Prelude (Unit)
+import Data.List.Lazy (nil)
+import Data.List.Types (List)
+
+wrongModule :: List Unit
+wrongModule = nil
diff --git a/tests/purs/failing/QualifiedErrorsUnificationLocal.out b/tests/purs/failing/QualifiedErrorsUnificationLocal.out
new file mode 100644
index 0000000000..a723e0d140
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnificationLocal.out
@@ -0,0 +1,26 @@
+Error found:
+in module Main
+at tests/purs/failing/QualifiedErrorsUnificationLocal.purs:10:15 - 10:18 (line 10, column 15 - line 10, column 18)
+
+  Could not match type
+                             
+    Data.List.Lazy.Types.List
+                             
+  (defined in module Data.List.Lazy.Types)
+  with type
+        
+    List
+        
+  (defined in module Main)
+
+while trying to match type List t0
+  with type List Unit
+while checking that expression nil
+  has type List Unit
+in value declaration wrongModule
+
+where t0 is an unknown type
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/QualifiedErrorsUnificationLocal.purs b/tests/purs/failing/QualifiedErrorsUnificationLocal.purs
new file mode 100644
index 0000000000..0fd79aec2e
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnificationLocal.purs
@@ -0,0 +1,10 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Prelude (Unit)
+import Data.List.Lazy (nil)
+
+data List (a :: Type)
+
+wrongModule :: List Unit
+wrongModule = nil
diff --git a/tests/purs/failing/QualifiedErrorsUnificationReexport.out b/tests/purs/failing/QualifiedErrorsUnificationReexport.out
new file mode 100644
index 0000000000..91ca58f910
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnificationReexport.out
@@ -0,0 +1,26 @@
+Error found:
+in module Main
+at tests/purs/failing/QualifiedErrorsUnificationReexport.purs:9:15 - 9:18 (line 9, column 15 - line 9, column 18)
+
+  Could not match type
+                             
+    Data.List.Lazy.Types.List
+                             
+  (defined in module Data.List.Lazy.Types)
+  with type
+                        
+    Data.List.Types.List
+                        
+  (defined in module Data.List.Types)
+
+while trying to match type List t0
+  with type List Unit
+while checking that expression nil
+  has type List Unit
+in value declaration wrongModule
+
+where t0 is an unknown type
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/QualifiedErrorsUnificationReexport.purs b/tests/purs/failing/QualifiedErrorsUnificationReexport.purs
new file mode 100644
index 0000000000..2627d4ba31
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnificationReexport.purs
@@ -0,0 +1,9 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Prelude (Unit)
+import Data.List.Lazy (nil)
+import Data.List (List)
+
+wrongModule :: List Unit
+wrongModule = nil
diff --git a/tests/purs/failing/QualifiedErrorsUnificationShadow.out b/tests/purs/failing/QualifiedErrorsUnificationShadow.out
new file mode 100644
index 0000000000..286cb9b113
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnificationShadow.out
@@ -0,0 +1,26 @@
+Error found:
+in module Main
+at tests/purs/failing/QualifiedErrorsUnificationShadow.purs:9:15 - 9:18 (line 9, column 15 - line 9, column 18)
+
+  Could not match type
+                             
+    Data.List.Lazy.Types.List
+                             
+  (defined in module Data.List.Lazy.Types)
+  with type
+                             
+    Data.List.Lazy.Types.List
+                             
+  (defined in module Data.List.Types)
+
+while trying to match type List t0
+  with type List Unit
+while checking that expression nil
+  has type List Unit
+in value declaration wrongModule
+
+where t0 is an unknown type
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/QualifiedErrorsUnificationShadow.purs b/tests/purs/failing/QualifiedErrorsUnificationShadow.purs
new file mode 100644
index 0000000000..45d3d59a20
--- /dev/null
+++ b/tests/purs/failing/QualifiedErrorsUnificationShadow.purs
@@ -0,0 +1,9 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Prelude (Unit)
+import Data.List.Lazy (nil)
+import Data.List.Types (List) as Data.List.Lazy.Types
+
+wrongModule :: Data.List.Lazy.Types.List Unit
+wrongModule = nil
diff --git a/tests/purs/failing/RowLacks.out b/tests/purs/failing/RowLacks.out
index bd424a618a..6c1c49c510 100644
--- a/tests/purs/failing/RowLacks.out
+++ b/tests/purs/failing/RowLacks.out
@@ -3,13 +3,13 @@ in module Main
 at tests/purs/failing/RowLacks.purs:16:9 - 16:66 (line 16, column 9 - line 16, column 66)
 
   No type class instance was found for
-                                
-    Prim.Row.Lacks "x"          
-                   ( x :: Int   
-                   , y :: Int   
-                   , z :: String
-                   )            
-                                
+                       
+    Lacks "x"          
+          ( x :: Int   
+          , y :: Int   
+          , z :: String
+          )            
+                       
 
 while applying a function lacksX
   of type Lacks @t1 "x" t2 => Proxy @(Row t1) t2 -> Proxy @(Row t3) (() @t3)
diff --git a/tests/purs/failing/RowsInKinds.out b/tests/purs/failing/RowsInKinds.out
index a226e71125..6b3c35fea3 100644
--- a/tests/purs/failing/RowsInKinds.out
+++ b/tests/purs/failing/RowsInKinds.out
@@ -5,7 +5,7 @@ at tests/purs/failing/RowsInKinds.purs:14:16 - 14:17 (line 14, column 16 - line
   Could not match kind
                
     ( z :: Type
-    | t25      
+    | t0       
     )          
                
   with kind
@@ -23,6 +23,8 @@ while checking that type Z
 while inferring the kind of P Z
 in type synonym Test3
 
+where t0 is an unknown type
+
 See https://github.com/purescript/documentation/blob/master/errors/KindsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/SkolemEscape.out b/tests/purs/failing/SkolemEscape.out
index 8217eff0aa..38512e1ce0 100644
--- a/tests/purs/failing/SkolemEscape.out
+++ b/tests/purs/failing/SkolemEscape.out
@@ -7,9 +7,9 @@ at tests/purs/failing/SkolemEscape.purs:8:1 - 8:19 (line 8, column 1 - line 8, c
     tests/purs/failing/SkolemEscape.purs:8:18 - 8:19 (line 8, column 18 - line 8, column 19)
 
   has escaped its scope, appearing in the type
-                        
-    (a0 -> a0) -> Number
-                        
+                             
+    (a0 -> a0) -> Prim.Number
+                             
 
 in the expression \x ->  
                     foo x
diff --git a/tests/purs/failing/SkolemEscape2.out b/tests/purs/failing/SkolemEscape2.out
index 98f7d3ad24..3f6024afaf 100644
--- a/tests/purs/failing/SkolemEscape2.out
+++ b/tests/purs/failing/SkolemEscape2.out
@@ -7,9 +7,9 @@ at tests/purs/failing/SkolemEscape2.purs:9:1 - 11:9 (line 9, column 1 - line 11,
     tests/purs/failing/SkolemEscape2.purs:10:21 - 10:34 (line 10, column 21 - line 10, column 34)
 
   has escaped its scope, appearing in the type
-                           
-    t1 -> t2 (STRef r0 Int)
-                           
+                                                          
+    t1 -> t2 (Control.Monad.ST.Internal.STRef r0 Prim.Int)
+                                                          
 
 in the expression \$0 ->                                        
                     ((bind $dictBind1) ((...) (...))) (\r ->    
diff --git a/tests/purs/failing/SkolemEscapeKinds.out b/tests/purs/failing/SkolemEscapeKinds.out
index a1732cc381..b624fc6380 100644
--- a/tests/purs/failing/SkolemEscapeKinds.out
+++ b/tests/purs/failing/SkolemEscapeKinds.out
@@ -7,9 +7,9 @@ at tests/purs/failing/SkolemEscapeKinds.purs:8:10 - 8:17 (line 8, column 10 - li
     tests/purs/failing/SkolemEscapeKinds.purs:8:16 - 8:17 (line 8, column 16 - line 8, column 17)
 
   has escaped its scope, appearing in the type
-         
-    Proxy
-         
+              
+    Main.Proxy
+              
 
 in type synonym B
 
diff --git a/tests/purs/failing/SuggestComposition.out b/tests/purs/failing/SuggestComposition.out
index a588608250..ed08f22fe9 100644
--- a/tests/purs/failing/SuggestComposition.out
+++ b/tests/purs/failing/SuggestComposition.out
@@ -3,13 +3,13 @@ in module SuggestComposition
 at tests/purs/failing/SuggestComposition.purs:7:5 - 7:6 (line 7, column 5 - line 7, column 6)
 
   Could not match type
-          
-    Record
-          
+               
+    Prim.Record
+               
   with type
-                
-    Function Int
-                
+                     
+    Prim.Function Int
+                     
 
 while trying to match type { g :: t0
                            | t1     
diff --git a/tests/purs/failing/Superclasses1.out b/tests/purs/failing/Superclasses1.out
index ed16d56c71..ea2b54cc8f 100644
--- a/tests/purs/failing/Superclasses1.out
+++ b/tests/purs/failing/Superclasses1.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/Superclasses1.purs:12:1 - 13:17 (line 12, column 1 - line 13, column 17)
 
   No type class instance was found for
-                  
-    Main.Su Number
-                  
+             
+    Su Number
+             
 
 while checking that expression #dict Su
   has type Su$Dict t0
diff --git a/tests/purs/failing/TypeClasses2.out b/tests/purs/failing/TypeClasses2.out
index 799aff9e9d..21a5a9bc12 100644
--- a/tests/purs/failing/TypeClasses2.out
+++ b/tests/purs/failing/TypeClasses2.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/TypeClasses2.purs:7:8 - 7:22 (line 7, column 8 - line 7, column 22)
 
   No type class instance was found for
-                    
-    Main.Show String
-                    
+               
+    Show String
+               
 
 while applying a function show
   of type Show t0 => t0 -> String
diff --git a/tests/purs/failing/TypeError.out b/tests/purs/failing/TypeError.out
index 0cc707d1bd..7b21aed68f 100644
--- a/tests/purs/failing/TypeError.out
+++ b/tests/purs/failing/TypeError.out
@@ -6,10 +6,12 @@ at tests/purs/failing/TypeError.purs:6:13 - 6:16 (line 6, column 13 - line 6, co
           
     String
           
+  (defined in module Prim)
   with type
        
     Int
        
+  (defined in module Prim)
 
 while checking that type String
   is at least as general as type Int
@@ -17,6 +19,6 @@ while checking that expression "A"
   has type Int
 in value declaration test
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/TypeError.purs b/tests/purs/failing/TypeError.purs
index 1c5c980067..d0c7d67f01 100644
--- a/tests/purs/failing/TypeError.purs
+++ b/tests/purs/failing/TypeError.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prelude
diff --git a/tests/purs/failing/TypeQualification1.out b/tests/purs/failing/TypeQualification1.out
new file mode 100644
index 0000000000..51bb828676
--- /dev/null
+++ b/tests/purs/failing/TypeQualification1.out
@@ -0,0 +1,24 @@
+Error found:
+in module Main
+at tests/purs/failing/TypeQualification1.purs:10:6 - 10:13 (line 10, column 6 - line 10, column 13)
+
+  Could not match type
+          
+    String
+          
+  (defined in module Prim)
+  with type
+        
+    L1.X
+        
+  (defined in module Lib1)
+
+while checking that type String
+  is at least as general as type X
+while checking that expression "wrong"
+  has type X
+in value declaration x1
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/TypeQualification1.purs b/tests/purs/failing/TypeQualification1.purs
new file mode 100644
index 0000000000..2599601f01
--- /dev/null
+++ b/tests/purs/failing/TypeQualification1.purs
@@ -0,0 +1,10 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Lib1 as L
+import Lib1 as L1
+import Lib2 as M
+import Lib3 as L
+
+x1 :: L1.X
+x1 = "wrong"
diff --git a/tests/purs/failing/TypeQualification1/Lib1.purs b/tests/purs/failing/TypeQualification1/Lib1.purs
new file mode 100644
index 0000000000..93b3eb1a96
--- /dev/null
+++ b/tests/purs/failing/TypeQualification1/Lib1.purs
@@ -0,0 +1,4 @@
+module Lib1 where
+
+data X
+data Y
diff --git a/tests/purs/failing/TypeQualification1/Lib2.purs b/tests/purs/failing/TypeQualification1/Lib2.purs
new file mode 100644
index 0000000000..25bae92a24
--- /dev/null
+++ b/tests/purs/failing/TypeQualification1/Lib2.purs
@@ -0,0 +1,4 @@
+module Lib2 where
+
+data X
+data Y
diff --git a/tests/purs/failing/TypeQualification1/Lib3.purs b/tests/purs/failing/TypeQualification1/Lib3.purs
new file mode 100644
index 0000000000..90bbf0439f
--- /dev/null
+++ b/tests/purs/failing/TypeQualification1/Lib3.purs
@@ -0,0 +1,5 @@
+module Lib3 where
+
+data X
+data Y
+data Z
diff --git a/tests/purs/failing/TypeQualification2.out b/tests/purs/failing/TypeQualification2.out
new file mode 100644
index 0000000000..8e85981538
--- /dev/null
+++ b/tests/purs/failing/TypeQualification2.out
@@ -0,0 +1,24 @@
+Error found:
+in module Main
+at tests/purs/failing/TypeQualification2.purs:10:6 - 10:13 (line 10, column 6 - line 10, column 13)
+
+  Could not match type
+          
+    String
+          
+  (defined in module Prim)
+  with type
+       
+    M.Y
+       
+  (defined in module Lib2)
+
+while checking that type String
+  is at least as general as type Y
+while checking that expression "wrong"
+  has type Y
+in value declaration x2
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/TypeQualification2.purs b/tests/purs/failing/TypeQualification2.purs
new file mode 100644
index 0000000000..5fa096ce8d
--- /dev/null
+++ b/tests/purs/failing/TypeQualification2.purs
@@ -0,0 +1,10 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Lib1 as L
+import Lib1 as L1
+import Lib2 as M
+import Lib3 as L
+
+x2 :: M.Y
+x2 = "wrong"
diff --git a/tests/purs/failing/TypeQualification2/Lib1.purs b/tests/purs/failing/TypeQualification2/Lib1.purs
new file mode 100644
index 0000000000..93b3eb1a96
--- /dev/null
+++ b/tests/purs/failing/TypeQualification2/Lib1.purs
@@ -0,0 +1,4 @@
+module Lib1 where
+
+data X
+data Y
diff --git a/tests/purs/failing/TypeQualification2/Lib2.purs b/tests/purs/failing/TypeQualification2/Lib2.purs
new file mode 100644
index 0000000000..25bae92a24
--- /dev/null
+++ b/tests/purs/failing/TypeQualification2/Lib2.purs
@@ -0,0 +1,4 @@
+module Lib2 where
+
+data X
+data Y
diff --git a/tests/purs/failing/TypeQualification2/Lib3.purs b/tests/purs/failing/TypeQualification2/Lib3.purs
new file mode 100644
index 0000000000..90bbf0439f
--- /dev/null
+++ b/tests/purs/failing/TypeQualification2/Lib3.purs
@@ -0,0 +1,5 @@
+module Lib3 where
+
+data X
+data Y
+data Z
diff --git a/tests/purs/failing/TypeQualification3.out b/tests/purs/failing/TypeQualification3.out
new file mode 100644
index 0000000000..41ca500c6f
--- /dev/null
+++ b/tests/purs/failing/TypeQualification3.out
@@ -0,0 +1,24 @@
+Error found:
+in module Main
+at tests/purs/failing/TypeQualification3.purs:10:6 - 10:13 (line 10, column 6 - line 10, column 13)
+
+  Could not match type
+          
+    String
+          
+  (defined in module Prim)
+  with type
+       
+    L.Z
+       
+  (defined in module Lib3)
+
+while checking that type String
+  is at least as general as type Z
+while checking that expression "wrong"
+  has type Z
+in value declaration x3
+
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
+or to contribute content related to this error.
+
diff --git a/tests/purs/failing/TypeQualification3.purs b/tests/purs/failing/TypeQualification3.purs
new file mode 100644
index 0000000000..3eda153039
--- /dev/null
+++ b/tests/purs/failing/TypeQualification3.purs
@@ -0,0 +1,10 @@
+-- @shouldFailWith TypeConstructorsDoNotUnify
+module Main where
+
+import Lib1 as L
+import Lib1 as L1
+import Lib2 as M
+import Lib3 as L
+
+x3 :: L.Z
+x3 = "wrong"
diff --git a/tests/purs/failing/TypeQualification3/Lib1.purs b/tests/purs/failing/TypeQualification3/Lib1.purs
new file mode 100644
index 0000000000..93b3eb1a96
--- /dev/null
+++ b/tests/purs/failing/TypeQualification3/Lib1.purs
@@ -0,0 +1,4 @@
+module Lib1 where
+
+data X
+data Y
diff --git a/tests/purs/failing/TypeQualification3/Lib2.purs b/tests/purs/failing/TypeQualification3/Lib2.purs
new file mode 100644
index 0000000000..25bae92a24
--- /dev/null
+++ b/tests/purs/failing/TypeQualification3/Lib2.purs
@@ -0,0 +1,4 @@
+module Lib2 where
+
+data X
+data Y
diff --git a/tests/purs/failing/TypeQualification3/Lib3.purs b/tests/purs/failing/TypeQualification3/Lib3.purs
new file mode 100644
index 0000000000..90bbf0439f
--- /dev/null
+++ b/tests/purs/failing/TypeQualification3/Lib3.purs
@@ -0,0 +1,5 @@
+module Lib3 where
+
+data X
+data Y
+data Z
diff --git a/tests/purs/failing/TypeSynonymsOverlappingUnnamedInstance.out b/tests/purs/failing/TypeSynonymsOverlappingUnnamedInstance.out
index d510bad034..8feebc15b4 100644
--- a/tests/purs/failing/TypeSynonymsOverlappingUnnamedInstance.out
+++ b/tests/purs/failing/TypeSynonymsOverlappingUnnamedInstance.out
@@ -9,8 +9,8 @@ at tests/purs/failing/TypeSynonymsOverlappingUnnamedInstance.purs:14:1 - 15:16 (
                        
   The following instances were found:
 
-    instance in module Main with type Convert String String (line 11, column 1 - line 12, column 16)
-    instance in module Main with type Convert String String (line 14, column 1 - line 15, column 16)
+    instance in module Main with type Main.Convert String String (line 11, column 1 - line 12, column 16)
+    instance in module Main with type Main.Convert String String (line 14, column 1 - line 15, column 16)
 
 
 in type class instance
diff --git a/tests/purs/failing/TypedBinders2.out b/tests/purs/failing/TypedBinders2.out
index ca46c046b8..ae49d55b48 100644
--- a/tests/purs/failing/TypedBinders2.out
+++ b/tests/purs/failing/TypedBinders2.out
@@ -3,13 +3,15 @@ in module Main
 at tests/purs/failing/TypedBinders2.purs:8:3 - 8:14 (line 8, column 3 - line 8, column 14)
 
   Could not match type
-        
-    Unit
-        
+                  
+    Data.Unit.Unit
+                  
+  (defined in module Data.Unit)
   with type
           
     String
           
+  (defined in module Prim)
 
 while checking that expression case $0 of       
                                  s -> log "Done"
@@ -25,6 +27,6 @@ where t1 is an unknown type
       t0 is an unknown type
       t2 is an unknown type
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/TypedBinders2.purs b/tests/purs/failing/TypedBinders2.purs
index 7262441163..a5de3d0f28 100644
--- a/tests/purs/failing/TypedBinders2.purs
+++ b/tests/purs/failing/TypedBinders2.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prelude
diff --git a/tests/purs/failing/TypedBinders3.out b/tests/purs/failing/TypedBinders3.out
index 0d061f3555..5b4b0aba42 100644
--- a/tests/purs/failing/TypedBinders3.out
+++ b/tests/purs/failing/TypedBinders3.out
@@ -6,16 +6,18 @@ at tests/purs/failing/TypedBinders3.purs:8:4 - 8:15 (line 8, column 4 - line 8,
        
     Int
        
+  (defined in module Prim)
   with type
           
     String
           
+  (defined in module Prim)
 
 while inferring the type of case 1 of   
                               0 -> true 
                               _ -> false
 in value declaration test
 
-See https://github.com/purescript/documentation/blob/master/errors/TypesDoNotUnify.md for more information,
+See https://github.com/purescript/documentation/blob/master/errors/TypeConstructorsDoNotUnify.md for more information,
 or to contribute content related to this error.
 
diff --git a/tests/purs/failing/TypedBinders3.purs b/tests/purs/failing/TypedBinders3.purs
index 3edcfd9404..af2dd9605b 100644
--- a/tests/purs/failing/TypedBinders3.purs
+++ b/tests/purs/failing/TypedBinders3.purs
@@ -1,4 +1,4 @@
--- @shouldFailWith TypesDoNotUnify
+-- @shouldFailWith TypeConstructorsDoNotUnify
 module Main where
 
 import Prelude
diff --git a/tests/purs/failing/TypedHole.out b/tests/purs/failing/TypedHole.out
index 9153ca38fc..11b78627e8 100644
--- a/tests/purs/failing/TypedHole.out
+++ b/tests/purs/failing/TypedHole.out
@@ -3,16 +3,16 @@ in module Main
 at tests/purs/failing/TypedHole.purs:8:8 - 8:13 (line 8, column 8 - line 8, column 13)
 
   Hole 'ummm' has the inferred type
-               
-    Effect Unit
-               
+                         
+    Effect Data.Unit.Unit
+                         
   You could substitute the hole with one of these values:
-                                                                    
-    Data.Monoid.mempty          :: forall m. Monoid m => m          
-    Effect.Class.Console.clear  :: forall m. MonadEffect m => m Unit
-    Effect.Console.clear        :: Effect Unit                      
-    Main.main                   :: Effect Unit                      
-                                                                    
+                                                                              
+    Data.Monoid.mempty          :: forall m. Monoid m => m                    
+    Effect.Class.Console.clear  :: forall m. MonadEffect m => m Data.Unit.Unit
+    Effect.Console.clear        :: Effect Data.Unit.Unit                      
+    Main.main                   :: Effect Data.Unit.Unit                      
+                                                                              
 
 in value declaration main
 
diff --git a/tests/purs/failing/TypedHole2.out b/tests/purs/failing/TypedHole2.out
index e8ef3673df..acafbac557 100644
--- a/tests/purs/failing/TypedHole2.out
+++ b/tests/purs/failing/TypedHole2.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/failing/TypedHole2.purs:7:16 - 7:21 (line 7, column 16 - line 7, column 21)
 
   Hole 'ummm' has the inferred type
-        
-    Unit
-        
+                  
+    Data.Unit.Unit
+                  
 
 in value declaration main
 
diff --git a/tests/purs/failing/TypedHole3.out b/tests/purs/failing/TypedHole3.out
index db08ba593b..b609f32a0e 100644
--- a/tests/purs/failing/TypedHole3.out
+++ b/tests/purs/failing/TypedHole3.out
@@ -7,23 +7,23 @@ at tests/purs/failing/TypedHole3.purs:4:10 - 4:15 (line 4, column 10 - line 4, c
     t0
       
   You could substitute the hole with one of these values:
-                                                                                                          
-    Control.Alt.alt               :: forall f a. Alt f => f a -> f a -> f a                               
-    Control.Alternative.guard     :: forall m. Alternative m => Boolean -> m Unit                         
-    Control.Applicative.liftA1    :: forall f a b. Applicative f => (a -> b) -> f a -> f b                
-    Control.Applicative.pure      :: forall f a. Applicative f => a -> f a                                
-    Control.Applicative.unless    :: forall m. Applicative m => Boolean -> m Unit -> m Unit               
-    Control.Applicative.when      :: forall m. Applicative m => Boolean -> m Unit -> m Unit               
-    Control.Apply.apply           :: forall f a b. Apply f => f (a -> b) -> f a -> f b                    
-    Control.Apply.applyFirst      :: forall a b f. Apply f => f a -> f b -> f a                           
-    Control.Apply.applySecond     :: forall a b f. Apply f => f a -> f b -> f b                           
-    Control.Apply.lift2           :: forall a b c f. Apply f => (a -> b -> c) -> f a -> ... -> ...        
-    Control.Apply.lift3           :: forall a b c d f. Apply f => (a -> b -> ...) -> f a -> ... -> ...    
-    Control.Apply.lift4           :: forall a b c d e f. Apply f => (a -> b -> ...) -> f a -> ... -> ...  
-    Control.Apply.lift5           :: forall a b c d e f g. Apply f => (a -> b -> ...) -> f a -> ... -> ...
-    Control.Biapplicative.bipure  :: forall w a b. Biapplicative w => a -> b -> w a b                     
-    Control.Biapply.biapply       :: forall w a b c d. Biapply w => w (a -> b) (c -> d) -> w a c -> w b d 
-                                                                                                          
+                                                                                                               
+    Control.Alt.alt               :: forall f a. Alt f => f a -> f a -> f a                                    
+    Control.Alternative.guard     :: forall m. Alternative m => Boolean -> m Data.Unit.Unit                    
+    Control.Applicative.liftA1    :: forall f a b. Applicative f => (a -> b) -> f a -> f b                     
+    Control.Applicative.pure      :: forall f a. Applicative f => a -> f a                                     
+    Control.Applicative.unless    :: forall m. Applicative m => Boolean -> m Data.Unit.Unit -> m Data.Unit.Unit
+    Control.Applicative.when      :: forall m. Applicative m => Boolean -> m Data.Unit.Unit -> m Data.Unit.Unit
+    Control.Apply.apply           :: forall f a b. Apply f => f (a -> b) -> f a -> f b                         
+    Control.Apply.applyFirst      :: forall a b f. Apply f => f a -> f b -> f a                                
+    Control.Apply.applySecond     :: forall a b f. Apply f => f a -> f b -> f b                                
+    Control.Apply.lift2           :: forall a b c f. Apply f => (a -> b -> c) -> f a -> ... -> ...             
+    Control.Apply.lift3           :: forall a b c d f. Apply f => (a -> b -> ...) -> f a -> ... -> ...         
+    Control.Apply.lift4           :: forall a b c d e f. Apply f => (a -> b -> ...) -> f a -> ... -> ...       
+    Control.Apply.lift5           :: forall a b c d e f g. Apply f => (a -> b -> ...) -> f a -> ... -> ...     
+    Control.Biapplicative.bipure  :: forall w a b. Biapplicative w => a -> b -> w a b                          
+    Control.Biapply.biapply       :: forall w a b c d. Biapply w => w (a -> b) (c -> d) -> w a c -> w b d      
+                                                                                                               
 
 in value declaration fn
 
diff --git a/tests/purs/failing/UnsupportedTypeInKind.out b/tests/purs/failing/UnsupportedTypeInKind.out
index b811914f36..ef04f30d2d 100644
--- a/tests/purs/failing/UnsupportedTypeInKind.out
+++ b/tests/purs/failing/UnsupportedTypeInKind.out
@@ -4,7 +4,7 @@ at tests/purs/failing/UnsupportedTypeInKind.purs:7:28 - 7:38 (line 7, column 28
 
   The type:
 
-    Ok => Type
+    Ok => Prim.Type
 
   is not supported in kinds.
 
diff --git a/tests/purs/warning/2542.out b/tests/purs/warning/2542.out
index 1b0cef80a1..1f8f4e5d87 100644
--- a/tests/purs/warning/2542.out
+++ b/tests/purs/warning/2542.out
@@ -5,9 +5,9 @@ at tests/purs/warning/2542.purs:16:1 - 16:18 (line 16, column 1 - line 16, colum
   No type declaration was provided for the top-level declaration of main.
   It is good practice to provide type declarations as a form of documentation.
   The inferred type of main was:
-               
-    Effect Unit
-               
+                                
+    Effect.Effect Data.Unit.Unit
+                                
 
 in value declaration main
 
diff --git a/tests/purs/warning/4256.out b/tests/purs/warning/4256.out
index cbf4467e21..2c4b7e4c26 100644
--- a/tests/purs/warning/4256.out
+++ b/tests/purs/warning/4256.out
@@ -23,9 +23,9 @@ Warning 2 of 2:
     No type declaration was provided for the top-level declaration of addNumberSuffix'.
     It is good practice to provide type declarations as a form of documentation.
     The inferred type of addNumberSuffix' was:
-                                                  
-      forall b34 c35 d36. b34 -> c35 -> d36 -> Int
-                                                  
+                                                       
+      forall b34 c35 d36. b34 -> c35 -> d36 -> Prim.Int
+                                                       
 
   in value declaration addNumberSuffix'
 
diff --git a/tests/purs/warning/4308.out b/tests/purs/warning/4308.out
index 37057ac6fe..d6e2520f7d 100644
--- a/tests/purs/warning/4308.out
+++ b/tests/purs/warning/4308.out
@@ -4,9 +4,9 @@ Warning 1 of 3:
   at tests/purs/warning/4308.purs:13:6 - 13:7 (line 13, column 6 - line 13, column 7)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in value declaration g
 
@@ -19,9 +19,9 @@ Warning 2 of 3:
   at tests/purs/warning/4308.purs:14:13 - 14:14 (line 14, column 13 - line 14, column 14)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in value declaration g
 
@@ -34,9 +34,9 @@ Warning 3 of 3:
   at tests/purs/warning/4308.purs:14:25 - 14:26 (line 14, column 25 - line 14, column 26)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
     in the following context:
 
       y :: Int
diff --git a/tests/purs/warning/MissingKindDeclaration.out b/tests/purs/warning/MissingKindDeclaration.out
index 5174fcff24..304f8e832f 100644
--- a/tests/purs/warning/MissingKindDeclaration.out
+++ b/tests/purs/warning/MissingKindDeclaration.out
@@ -5,9 +5,9 @@ Warning 1 of 4:
 
     The inferred kind for the data declaration Proxy contains polymorphic kinds.
     Consider adding a top-level kind signature as a form of documentation.
-                                       
-      data Proxy :: forall k. k -> Type
-                                       
+                                            
+      data Proxy :: forall k. k -> Prim.Type
+                                            
 
   in type constructor Proxy
 
@@ -21,9 +21,9 @@ Warning 2 of 4:
 
     The inferred kind for the type declaration Natural contains polymorphic kinds.
     Consider adding a top-level kind signature as a form of documentation.
-                                                                  
-      type Natural :: forall k. (k -> Type) -> (k -> Type) -> Type
-                                                                  
+                                                                                 
+      type Natural :: forall k. (k -> Prim.Type) -> (k -> Prim.Type) -> Prim.Type
+                                                                                 
 
   in type synonym Natural
 
@@ -37,9 +37,9 @@ Warning 3 of 4:
 
     The inferred kind for the newtype declaration F contains polymorphic kinds.
     Consider adding a top-level kind signature as a form of documentation.
-                                              
-      newtype F :: forall k. k -> Type -> Type
-                                              
+                                                        
+      newtype F :: forall k. k -> Prim.Type -> Prim.Type
+                                                        
 
   in type constructor F
 
@@ -53,9 +53,9 @@ Warning 4 of 4:
 
     The inferred kind for the class declaration Clazz contains polymorphic kinds.
     Consider adding a top-level kind signature as a form of documentation.
-                                                                  
-      class Clazz :: forall k1 k2 k3. k1 -> k2 -> k3 -> Constraint
-                                                                  
+                                                                       
+      class Clazz :: forall k1 k2 k3. k1 -> k2 -> k3 -> Prim.Constraint
+                                                                       
 
   in type class declaration for Clazz
 
diff --git a/tests/purs/warning/MissingTypeDeclaration.out b/tests/purs/warning/MissingTypeDeclaration.out
index add92fa0c7..2e9f3b611b 100644
--- a/tests/purs/warning/MissingTypeDeclaration.out
+++ b/tests/purs/warning/MissingTypeDeclaration.out
@@ -5,9 +5,9 @@ at tests/purs/warning/MissingTypeDeclaration.purs:4:1 - 4:6 (line 4, column 1 -
   No type declaration was provided for the top-level declaration of x.
   It is good practice to provide type declarations as a form of documentation.
   The inferred type of x was:
-       
-    Int
-       
+            
+    Prim.Int
+            
 
 in value declaration x
 
diff --git a/tests/purs/warning/NewtypeInstance.out b/tests/purs/warning/NewtypeInstance.out
index b6dd688801..b537ec22f8 100644
--- a/tests/purs/warning/NewtypeInstance.out
+++ b/tests/purs/warning/NewtypeInstance.out
@@ -3,9 +3,9 @@ in module Main
 at tests/purs/warning/NewtypeInstance.purs:8:1 - 8:38 (line 8, column 1 - line 8, column 38)
 
   The derived newtype instance for
-                  
-    Data.Ord.Ord X
-                  
+                       
+    Data.Ord.Ord Main.X
+                       
   does not include a derived superclass instance for Data.Eq.Eq.
 
 in value declaration ordX
diff --git a/tests/purs/warning/NewtypeInstance2.out b/tests/purs/warning/NewtypeInstance2.out
index e9afcb3d74..7087aa812b 100644
--- a/tests/purs/warning/NewtypeInstance2.out
+++ b/tests/purs/warning/NewtypeInstance2.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/warning/NewtypeInstance2.purs:15:1 - 15:86 (line 15, column 1 - line 15, column 86)
 
   The derived newtype instance for
-                                  
-    Main.MonadWriter w0           
-                     (MyWriter w0)
-                                  
+                                       
+    Main.MonadWriter w0                
+                     (Main.MyWriter w0)
+                                       
   does not include a derived superclass instance for Control.Monad.Monad.
 
 in value declaration monadWriterMyWriter
diff --git a/tests/purs/warning/NewtypeInstance3.out b/tests/purs/warning/NewtypeInstance3.out
index bb3e96b4db..919fdd78af 100644
--- a/tests/purs/warning/NewtypeInstance3.out
+++ b/tests/purs/warning/NewtypeInstance3.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/warning/NewtypeInstance3.purs:21:1 - 21:86 (line 21, column 1 - line 21, column 86)
 
   The derived newtype instance for
-                                  
-    Main.MonadWriter w0           
-                     (MyWriter w0)
-                                  
+                                       
+    Main.MonadWriter w0                
+                     (Main.MyWriter w0)
+                                       
   does not include a derived superclass instance for Main.MonadTell.
 
 in value declaration monadWriterMyWriter
diff --git a/tests/purs/warning/NewtypeInstance4.out b/tests/purs/warning/NewtypeInstance4.out
index 2d81d13624..29066f2b0e 100644
--- a/tests/purs/warning/NewtypeInstance4.out
+++ b/tests/purs/warning/NewtypeInstance4.out
@@ -3,10 +3,10 @@ in module Main
 at tests/purs/warning/NewtypeInstance4.purs:23:1 - 23:86 (line 23, column 1 - line 23, column 86)
 
   The derived newtype instance for
-                                  
-    Main.MonadWriter w0           
-                     (MyWriter w0)
-                                  
+                                       
+    Main.MonadWriter w0                
+                     (Main.MyWriter w0)
+                                       
   implies an superclass instance for Main.MonadTell which could not be verified.
 
 in value declaration monadWriterMyWriter
diff --git a/tests/purs/warning/UnambiguousQuantifiedKind.out b/tests/purs/warning/UnambiguousQuantifiedKind.out
index d3b70ea42e..ae569e730f 100644
--- a/tests/purs/warning/UnambiguousQuantifiedKind.out
+++ b/tests/purs/warning/UnambiguousQuantifiedKind.out
@@ -5,9 +5,9 @@ at tests/purs/warning/UnambiguousQuantifiedKind.purs:12:1 - 12:11 (line 12, colu
   No type declaration was provided for the top-level declaration of test2.
   It is good practice to provide type declarations as a form of documentation.
   The inferred type of test2 was:
-       
-    Int
-       
+            
+    Prim.Int
+            
 
 in value declaration test2
 
diff --git a/tests/purs/warning/WildcardInferredType.out b/tests/purs/warning/WildcardInferredType.out
index 91aabf9a1e..50f64ee2f9 100644
--- a/tests/purs/warning/WildcardInferredType.out
+++ b/tests/purs/warning/WildcardInferredType.out
@@ -4,9 +4,9 @@ Warning 1 of 2:
   at tests/purs/warning/WildcardInferredType.purs:7:6 - 7:7 (line 7, column 6 - line 7, column 7)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in value declaration y
 
@@ -19,9 +19,9 @@ Warning 2 of 2:
   at tests/purs/warning/WildcardInferredType.purs:5:10 - 5:11 (line 5, column 10 - line 5, column 11)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in value declaration x
 
diff --git a/tests/purs/warning/WildcardInferredType2.out b/tests/purs/warning/WildcardInferredType2.out
index 52cbc66ce7..83ff0e9dc0 100644
--- a/tests/purs/warning/WildcardInferredType2.out
+++ b/tests/purs/warning/WildcardInferredType2.out
@@ -4,9 +4,9 @@ Warning 1 of 5:
   at tests/purs/warning/WildcardInferredType2.purs:10:6 - 10:7 (line 10, column 6 - line 10, column 7)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in value declaration x
 
@@ -19,9 +19,9 @@ Warning 2 of 5:
   at tests/purs/warning/WildcardInferredType2.purs:51:9 - 51:10 (line 51, column 9 - line 51, column 10)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in binding group foxtrot, echo
 
@@ -34,9 +34,9 @@ Warning 3 of 5:
   at tests/purs/warning/WildcardInferredType2.purs:54:8 - 54:9 (line 54, column 8 - line 54, column 9)
 
     Wildcard type definition has the inferred type
-         
-      Int
-         
+              
+      Prim.Int
+              
     in the following context:
 
       m :: Int
@@ -55,9 +55,9 @@ Warning 4 of 5:
     No type declaration was provided for the top-level declaration of delta.
     It is good practice to provide type declarations as a form of documentation.
     The inferred type of delta was:
-                
-      Int -> Int
-                
+                          
+      Prim.Int -> Prim.Int
+                          
 
   in binding group delta, charlie
 
@@ -72,9 +72,9 @@ Warning 5 of 5:
     No type declaration was provided for the top-level declaration of alpha.
     It is good practice to provide type declarations as a form of documentation.
     The inferred type of alpha was:
-         
-      Int
-         
+              
+      Prim.Int
+              
 
   in value declaration alpha