diff --git a/.hlint.yaml b/.hlint.yaml
--- a/.hlint.yaml
+++ b/.hlint.yaml
@@ -16,6 +16,7 @@
 
 - extensions:
   - default: false
+  - name: [ImportQualifiedPost]
   - name: [DeriveDataTypeable, DeriveFunctor, GeneralizedNewtypeDeriving, NoMonomorphismRestriction, OverloadedStrings]
   - name: [MultiWayIf, PatternGuards, RecordWildCards, ViewPatterns, PatternSynonyms, TupleSections, LambdaCase]
   - name: [Rank2Types, ScopedTypeVariables]
@@ -26,6 +27,7 @@
   - name: [TemplateHaskell]
   - name: [DerivingVia, DeriveGeneric, DataKinds]
   - {name: CPP, within: [HsColour, Config.Yaml, Test.Annotations]} # so it can be disabled to avoid GPL code
+  - {name: CPP, within: CmdLine} # Don't think this one is really necessary
 
 - flags:
   - default: false
@@ -70,7 +72,7 @@
 
 # doesn't fit with the other statements
 - ignore: {name: Use let, within: [HLint, Test.All]}
-# this const has meaingful argument names
+# this const has meaningful argument names
 - ignore: {name: Use const, within: Config.Yaml}
 # TEMPORARY: this lint is deleted on HEAD
 - ignore: {name: Use String}
diff --git a/CHANGES.txt b/CHANGES.txt
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,5 +1,36 @@
 Changelog for HLint (* = breaking change)
 
+3.6, released 2023-06-26
+    #1522, define __GLASGOW_HASKELL__ for cmdCpp
+    #1519, don't suggest removing brackets that result in a parse error
+    #1512, add hints to convert for [1..n] to replicateM n
+    #1430, add ignore-suggestions flag
+    #1517, support NO_COLOR
+    #1505, don't suggest redundant brackets around constraints
+    #1478, Fix no warn on (x.y) by treating x.y as atom
+    #1481, more hints about concat/concatMap
+    #1485, add more hints about using a Functor on a literal tuple
+    #1479, add specialised not hints for notElem/notNull
+    #1437, don't add/remove Monad constraints in replacements
+    #1475, rules for (elem False) and (notElem True)
+    #1476, generalise map-consuming rules from lists to Foldables/Traversables
+    #1480, add hints about notElem and notNull
+    #1482, support SARIF output
+    #1470, drop support for GHC 9.0
+*   #1470, move to GHC 9.6 parser
+    #1449, add some more generalize hints that suggest fmap instead of map
+    Never suggest concatForM_, because it doesn't exist
+    #1467, and groups for warning on partial functions
+    #1465, improve the timing information with -v flag
+    #1454, filter Just . map f ==> map Just . mapMaybe f
+    #1452, add more evaluate rules, e.g. fromJust (Just x) ==> x
+    #1488, add <$>/<&> hints for Either
+    #1447, make <$> hints also work on <&> (dualized)
+    #1450, suggest nub/sort ==> nubSort with the extra hints
+    #1451, isJust y && (x == fromJust y) ==> Just x == y
+    #578, don't suggest numeric underscores for < 5 digits
+    #1428, rename "Use map" hints that introduce tuple sections
+    #1424, don't suggest sortOn; suggest avoiding `reverse . sort`
 3.5, released 2022-09-20
     #1421, change zip/repeat to map with tuple section
     #1418, add more QuickCheck hints
diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright Neil Mitchell 2006-2022.
+Copyright Neil Mitchell 2006-2023.
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -57,7 +57,7 @@
 
 The first hint is marked as an warning, because using `concatMap` in preference to the two separate functions is always desirable. In contrast, the removal of brackets is probably a good idea, but not always. Reasons that a hint might be a suggestion include requiring an additional import, something not everyone agrees on, and functions only available in more recent versions of the base library.
 
-Any configuration can be done via [.hlint.yaml](./README.md#customizing-the-hints) file.
+Any configuration can be done via [.hlint.yaml](./README.md#customizing-the-hints) file. Any other file name, such as `.hlint.yml`, can only be used explicitly with the `--hint=FILE` option.
 
 **Bug reports:** The suggested replacement should be equivalent - please report all incorrect suggestions not mentioned as known limitations.
 
@@ -98,6 +98,7 @@
 * [hint-man](https://github.com/apps/hint-man) automatically submits reviews to opened pull requests in your repositories with inline hints.
 * [CircleCI](https://circleci.com/orbs/registry/orb/haskell-works/hlint) has a plugin to run HLint more easily.
 * [haskell/actions](https://github.com/haskell/actions) has `hlint-setup` and `hlint-run` actions for GitHub.
+* [haskell-actions/hlint-scan](https://github.com/haskell-actions/hlint-scan) is a GitHub action using HLint for [code scanning](https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/about-code-scanning).
 
 ### Automatically Applying Hints
 
diff --git a/data/default.yaml b/data/default.yaml
--- a/data/default.yaml
+++ b/data/default.yaml
@@ -51,6 +51,9 @@
 #
 # Generalise map to fmap, ++ to <>
 # - group: {name: generalise, enabled: true}
+#
+# Warn on use of partial functions
+# - group: {name: partial, enabled: true}
 
 
 # Ignore some builtin hints
diff --git a/data/do-block.yaml b/data/do-block.yaml
new file mode 100644
--- /dev/null
+++ b/data/do-block.yaml
@@ -0,0 +1,2 @@
+- ignore: { }
+- warn: {lhs: "case m of Just x -> y; Nothing -> Nothing", rhs: "do x <- m; y"}
diff --git a/data/hlint.yaml b/data/hlint.yaml
--- a/data/hlint.yaml
+++ b/data/hlint.yaml
@@ -6,30 +6,34 @@
 - package:
     name: base
     modules:
-    - import Prelude
+    - import Control.Applicative
     - import Control.Arrow
+    - import Control.Concurrent.Chan
     - import Control.Exception
+    - import Control.Exception.Base
     - import Control.Monad
     - import Control.Monad.Trans.State
-    - import qualified Data.Foldable
-    - import Data.Foldable(asum, sequenceA_, traverse_, for_)
-    - import Data.Traversable(traverse, for)
-    - import Control.Applicative
     - import Data.Bifunctor
+    - import Data.Char
+    - import Data.Either
+    - import Data.Fixed
+    - import Data.Foldable(asum, sequenceA_, traverse_, for_)
     - import Data.Function
     - import Data.Int
-    - import Data.Char
     - import Data.List as Data.List
     - import Data.List as X
+    - import Data.List.NonEmpty
     - import Data.Maybe
     - import Data.Monoid
+    - import Data.Ratio
+    - import Data.Traversable(traverse, for)
+    - import Numeric
+    - import Prelude
+    - import System.Exit
     - import System.IO
-    - import Control.Concurrent.Chan
     - import System.Mem.Weak
-    - import Control.Exception.Base
-    - import System.Exit
-    - import Data.Either
-    - import Numeric
+    - import Text.Read
+    - import qualified Data.Foldable
 
     - import IO as System.IO
     - import List as Data.List
@@ -112,11 +116,9 @@
     - warn: {lhs: head (sortBy f x), rhs: minimumBy f x, side: isCompare f}
     - warn: {lhs: last (sortBy f x), rhs: maximumBy f x, side: isCompare f}
     - warn: {lhs: reverse (sortBy f x), rhs: sortBy (flip f) x, name: Avoid reverse, side: isCompare f, note: Stabilizes sort order}
-    - warn: {lhs: sortBy (flip (comparing f)), rhs: sortOn (Down . f)}
-    - warn: {lhs: sortBy (comparing f), rhs: sortOn f, side: notEq f fst && notEq f snd}
+    - warn: {lhs: sortBy (flip (comparing f)), rhs: sortBy (comparing (Data.Ord.Down . f))}
     - warn: {lhs: reverse (sortOn f x), rhs: sortOn (Data.Ord.Down . f) x, name: Avoid reverse, note: Stabilizes sort order}
-    # This suggestion likely costs performance, see https://github.com/ndmitchell/hlint/issues/669#issuecomment-607154496
-    # - warn: {lhs: reverse (sort x), rhs: sortOn Data.Ord.Down x, name: Avoid reverse, note: Stabilizes sort order}
+    - warn: {lhs: reverse (sort x), rhs: sortBy (comparing Data.Ord.Down) x, name: Avoid reverse, note: Stabilizes sort order}
     - hint: {lhs: flip (g `on` h), rhs: flip g `on` h, name: Move flip}
     - hint: {lhs: (f `on` g) `on` h, rhs: f `on` (g . h), name: Fuse on/on}
     - warn: {lhs: if a >= b then a else b, rhs: max a b}
@@ -144,6 +146,7 @@
 
     - warn: {lhs: concat (map f x), rhs: concatMap f x}
     - warn: {lhs: concat (f <$> x), rhs: concatMap f x}
+    - warn: {lhs: concat (x <&> f), rhs: concatMap f x}
     - warn: {lhs: concat (fmap f x), rhs: concatMap f x}
     - hint: {lhs: "concat [a, b]", rhs: a ++ b}
     - hint: {lhs: map f (map g x), rhs: map (f . g) x, name: Use map once}
@@ -152,6 +155,8 @@
     - warn: {lhs: take n (repeat x), rhs: replicate n x}
     - warn: {lhs: map f (replicate n x), rhs: replicate n (f x)}
     - warn: {lhs: map f (repeat x), rhs: repeat (f x)}
+    - warn: {lhs: concatMap f (repeat x), rhs: cycle (f x)}
+    - warn: {lhs: concat (repeat x), rhs: cycle x}
     - warn: {lhs: "cycle [x]", rhs: repeat x}
     - warn: {lhs: head (reverse x), rhs: last x}
     - warn: {lhs: last (reverse x), rhs: head x, note: IncreasesLaziness}
@@ -173,6 +178,8 @@
     - warn: {lhs: foldr (.) id l z, rhs: foldr ($) z l}
     - warn: {lhs: span (not . p), rhs: break p}
     - warn: {lhs: break (not . p), rhs: span p}
+    - warn: {lhs: span (notElem x), rhs: break (elem x), name: Use break}
+    - warn: {lhs: break (notElem x), rhs: span (elem x), name: Use span}
     - warn: {lhs: "(takeWhile p x, dropWhile p x)", rhs: span p x, note: DecreasesLaziness}
     - warn: {lhs: fst (span p x), rhs: takeWhile p x}
     - warn: {lhs: snd (span p x), rhs: dropWhile p x}
@@ -206,7 +213,9 @@
     - hint: {lhs: "\\x -> [x]", rhs: "(:[])", name: "Use :"}
     - hint: {lhs: map f (zip x y), rhs: zipWith (curry f) x y, side: not (isApp f)}
     - hint: {lhs: "map f (fromMaybe [] x)", rhs: "maybe [] (map f) x"}
+    - hint: {lhs: "concatMap f (fromMaybe [] x)", rhs: "maybe [] (concatMap f) x"}
     - warn: {lhs: not (elem x y), rhs: notElem x y}
+    - warn: {lhs: not (notElem x y), rhs: elem x y}
     - hint: {lhs: foldr f z (map g x), rhs: foldr (f . g) z x, name: Fuse foldr/map}
     - warn: {lhs: "x ++ concatMap (' ':) y", rhs: "unwords (x:y)"}
     - warn: {lhs: intercalate " ", rhs: unwords}
@@ -230,6 +239,10 @@
     - warn: {lhs: notElem False, rhs: and}
     - warn: {lhs: True `elem` l, rhs: or l}
     - warn: {lhs: False `notElem` l, rhs: and l}
+    - warn: {lhs: elem False, rhs: any not, name: Use any}
+    - warn: {lhs: notElem True, rhs: all not, name: Use all}
+    - warn: {lhs: False `elem` l, rhs: any not l, name: Use any}
+    - warn: {lhs: True `notElem` l, rhs: all not l, name: Use all}
     - warn: {lhs: findIndex ((==) a), rhs: elemIndex a}
     - warn: {lhs: findIndex (a ==), rhs: elemIndex a}
     - warn: {lhs: findIndex (== a), rhs: elemIndex a}
@@ -254,9 +267,9 @@
     - warn: {lhs: "foldl (\\x _ -> a) b [1..c]", rhs: "iterate (\\x -> a) b !! c"}
     - warn: {lhs: iterate id, rhs: repeat}
     - warn: {lhs: zipWith f (repeat x), rhs: map (f x)}
-    - warn: {lhs: zip (repeat x), rhs: "map (_noParen_ x,)", note: RequiresExtension TupleSections}
+    - warn: {lhs: zip (repeat x), rhs: "map (_noParen_ x,)", note: RequiresExtension TupleSections, name: "Use map with tuple-section"}
     - warn: {lhs: zipWith f y (repeat z), rhs: map (`f` z) y}
-    - warn: {lhs: zip y (repeat z), rhs: "map (,_noParen_ z) y", note: RequiresExtension TupleSections}
+    - warn: {lhs: zip y (repeat z), rhs: "map (,_noParen_ z) y", note: RequiresExtension TupleSections, name: "Use map with tuple-section"}
     - warn: {lhs: listToMaybe (filter p x), rhs: find p x}
     - warn: {lhs: zip (take n x) (take n y), rhs: take n (zip x y)}
     - warn: {lhs: zip (take n x) (take m y), rhs: take (min n m) (zip x y), side: notEq n m, note: [IncreasesLaziness, DecreasesLaziness], name: Redundant take}
@@ -278,17 +291,27 @@
     - warn: {lhs: traverse (pure . f) x, rhs: pure (fmap f x), name: "Traversable law"}
     - warn: {lhs: sequenceA (map f x), rhs: traverse f x}
     - warn: {lhs: sequenceA (f <$> x), rhs: traverse f x}
+    - warn: {lhs: sequenceA (x <&> f), rhs: traverse f x}
     - warn: {lhs: sequenceA (fmap f x), rhs: traverse f x}
     - warn: {lhs: sequenceA_ (map f x), rhs: traverse_ f x}
     - warn: {lhs: sequenceA_ (f <$> x), rhs: traverse_ f x}
+    - warn: {lhs: sequenceA_ (x <&> f), rhs: traverse_ f x}
     - warn: {lhs: sequenceA_ (fmap f x), rhs: traverse_ f x}
     - warn: {lhs: foldMap id, rhs: fold}
     - warn: {lhs: fold (f <$> x), rhs: foldMap f x}
+    - warn: {lhs: fold (x <&> f), rhs: foldMap f x}
     - warn: {lhs: fold (fmap f x), rhs: foldMap f x}
     - warn: {lhs: fold (map f x), rhs: foldMap f x}
-    - warn: {lhs: foldMap f (g <$> x), rhs: foldMap (f . g) x, name: Fuse foldMap/fmap}
+    - warn: {lhs: foldMap f (g <$> x), rhs: foldMap (f . g) x, name: Fuse foldMap/<$>}
+    - warn: {lhs: foldMap f (x <&> g), rhs: foldMap (f . g) x, name: Fuse foldMap/<&>}
     - warn: {lhs: foldMap f (fmap g x), rhs: foldMap (f . g) x, name: Fuse foldMap/fmap}
     - warn: {lhs: foldMap f (map g x), rhs: foldMap (f . g) x, name: Fuse foldMap/map}
+    - warn: {lhs: traverse f (fmap g x), rhs: traverse (f . g) x, name: Fuse traverse/fmap}
+    - warn: {lhs: traverse f (g <$> x), rhs: traverse (f . g) x, name: Fuse traverse/<$>}
+    - warn: {lhs: traverse f (x <&> g), rhs: traverse (f . g) x, name: Fuse traverse/<&>}
+    - warn: {lhs: traverse_ f (fmap g x), rhs: traverse_ (f . g) x, name: Fuse traverse_/fmap}
+    - warn: {lhs: traverse_ f (g <$> x), rhs: traverse_ (f . g) x, name: Fuse traverse_/<$>}
+    - warn: {lhs: traverse_ f (x <&> g), rhs: traverse_ (f . g) x, name: Fuse traverse_/<&>}
 
     # BY
 
@@ -450,10 +473,13 @@
 
     - warn: {lhs: fmap f (fmap g x), rhs: fmap (f . g) x, name: Functor law}
     - warn: {lhs: f <$> g <$> x, rhs: f . g <$> x, name: Functor law}
+    - warn: {lhs: x <&> g <&> f, rhs: x <&> f . g, name: Functor law}
     - warn: {lhs: fmap id, rhs: id, name: Functor law}
     - warn: {lhs: id <$> x, rhs: x, name: Functor law}
+    - warn: {lhs: x <&> id, rhs: x, name: Functor law}
     - hint: {lhs: fmap f $ x, rhs: f <$> x, side: isApp x || isAtom x}
     - hint: {lhs: \x -> a <$> b x, rhs: fmap a . b}
+    - hint: {lhs: \x -> b x <&> a, rhs: fmap a . b}
     - hint: {lhs: x *> pure y, rhs: x Data.Functor.$> y}
     - hint: {lhs: x *> return y, rhs: x Data.Functor.$> y}
     - hint: {lhs: pure x <* y, rhs: x Data.Functor.<$ y}
@@ -464,6 +490,12 @@
     - hint: {lhs: x <&> const y, rhs: x Data.Functor.$> y}
     - hint: {lhs: x <&> pure y, rhs: x Data.Functor.$> y}
     - hint: {lhs: x <&> return y, rhs: x Data.Functor.$> y}
+    - warn: {lhs: "fmap f (x,b)", rhs: "(x,f b)", name: Using fmap on tuple}
+    - warn: {lhs: "f <$> (x,b)", rhs: "(x,f b)", name: Using <$> on tuple}
+    - warn: {lhs: "(x,b) <&> f", rhs: "(x,f b)", name: Using <&> on tuple}
+    - warn: {lhs: "fmap f (x,y,b)", rhs: "(x,y,f b)", name: Using fmap on tuple}
+    - warn: {lhs: "f <$> (x,y,b)", rhs: "(x,y,f b)", name: Using <$> on tuple}
+    - warn: {lhs: "(x,y,b) <&> f", rhs: "(x,y,f b)", name: Using <&> on tuple}
 
     # APPLICATIVE
 
@@ -507,23 +539,29 @@
     - warn: {lhs: sequence (map f x), rhs: mapM f x}
     - warn: {lhs: sequence_ (map f x), rhs: mapM_ f x}
     - warn: {lhs: sequence (f <$> x), rhs: mapM f x}
+    - warn: {lhs: sequence (x <&> f), rhs: mapM f x}
     - warn: {lhs: sequence (fmap f x), rhs: mapM f x}
     - warn: {lhs: sequence_ (f <$> x), rhs: mapM_ f x}
+    - warn: {lhs: sequence_ (x <&> f), rhs: mapM_ f x}
     - warn: {lhs: sequence_ (fmap f x), rhs: mapM_ f x}
     - hint: {lhs: flip mapM, rhs: Control.Monad.forM}
     - hint: {lhs: flip mapM_, rhs: Control.Monad.forM_}
     - hint: {lhs: flip forM, rhs: mapM}
     - hint: {lhs: flip forM_, rhs: mapM_}
     - warn: {lhs: when (not x), rhs: unless x}
+    - warn: {lhs: when (notElem x y), rhs: unless (elem x y), name: Use unless}
     - warn: {lhs: unless (not x), rhs: when x}
+    - warn: {lhs: unless (notElem x y), rhs: when (elem x y), name: Use when}
     - warn: {lhs: x >>= id, rhs: Control.Monad.join x}
     - warn: {lhs: id =<< x, rhs: Control.Monad.join x}
     - hint: {lhs: join (f <$> x), rhs: f =<< x}
+    - hint: {lhs: join (x <&> f), rhs: f =<< x}
     - hint: {lhs: join (fmap f x), rhs: f =<< x}
     - hint: {lhs: a >> pure (), rhs: Control.Monad.void a, side: isAtom a || isApp a}
     - hint: {lhs: a >> return (), rhs: Control.Monad.void a, side: isAtom a || isApp a}
     - warn: {lhs: fmap (const ()), rhs: Control.Monad.void}
     - warn: {lhs: const () <$> x, rhs: Control.Monad.void x}
+    - warn: {lhs: x <&> const (), rhs: Control.Monad.void x}
     - warn: {lhs: () <$ x, rhs: Control.Monad.void x}
     - warn: {lhs: flip (>=>), rhs: (<=<)}
     - warn: {lhs: flip (<=<), rhs: (>=>)}
@@ -542,7 +580,9 @@
     - warn: {lhs: fmap f (pure x), rhs: pure (f x)}
     - warn: {lhs: fmap f (return x), rhs: return (f x)}
     - warn: {lhs: f <$> pure x, rhs: pure (f x)}
+    - warn: {lhs: pure x <&> f, rhs: pure (f x)}
     - warn: {lhs: f <$> return x, rhs: return (f x)}
+    - warn: {lhs: return x <&> f, rhs: return (f x)}
     - warn: {lhs: mapM (uncurry f) (zip l m), rhs: zipWithM f l m}
     - warn: {lhs: mapM_ (void . f), rhs: mapM_ f}
     - warn: {lhs: forM_ x (void . f), rhs: forM_ x f}
@@ -553,6 +593,10 @@
     - warn: {lhs: return x *> m, rhs: m}
     - warn: {lhs: pure x >> m, rhs: m}
     - warn: {lhs: return x >> m, rhs: m}
+    - warn: {lhs: "forM [1..n] (const f)", rhs: replicateM n f}
+    - warn: {lhs: "for [1..n] (const f)", rhs: replicateM n f}
+    - warn: {lhs: "forM [1..n] (\\_ -> x)", rhs: replicateM n x}
+    - warn: {lhs: "for [1..n] (\\_ -> x)", rhs: replicateM n x}
 
     # STATE MONAD
 
@@ -562,6 +606,7 @@
     # MONAD LIST
 
     - warn: {lhs: unzip <$> mapM f x, rhs: Control.Monad.mapAndUnzipM f x}
+    - warn: {lhs: mapM f x <&> unzip, rhs: Control.Monad.mapAndUnzipM f x}
     - warn: {lhs: fmap unzip (mapM f x), rhs: Control.Monad.mapAndUnzipM f x}
     - warn: {lhs: sequence (zipWith f x y), rhs: Control.Monad.zipWithM f x y}
     - warn: {lhs: sequence_ (zipWith f x y), rhs: Control.Monad.zipWithM_ f x y}
@@ -587,7 +632,7 @@
     - warn: {lhs: flip traverse_, rhs: for_}
     - warn: {lhs: flip for_, rhs: traverse_}
     - warn: {lhs: foldr (*>) (pure ()), rhs: sequenceA_}
-    - warn: {lhs: foldr (*>) (return ()), rhs: sequenceA_}
+    - warn: {lhs: foldr (*>) (return ()), rhs: sequence_}
     - warn: {lhs: foldr (<|>) empty, rhs: asum}
     - warn: {lhs: liftA2 (flip ($)), rhs: (<**>)}
     - warn: {lhs: liftA2 f (pure x), rhs: fmap (f x)}
@@ -645,6 +690,7 @@
     - warn: {lhs: "maybe [] (:[])", rhs: maybeToList}
     - warn: {lhs: catMaybes (map f x), rhs: mapMaybe f x}
     - warn: {lhs: catMaybes (f <$> x), rhs: mapMaybe f x}
+    - warn: {lhs: catMaybes (x <&> f), rhs: mapMaybe f x}
     - warn: {lhs: catMaybes (fmap f x), rhs: mapMaybe f x}
     - hint: {lhs: case x of Nothing -> y; Just a -> a , rhs: Data.Maybe.fromMaybe y x, side: isAtom y, name: Replace case with fromMaybe}
     - hint: {lhs: case x of Just a -> a; Nothing -> y, rhs: Data.Maybe.fromMaybe y x, side: isAtom y, name: Replace case with fromMaybe}
@@ -654,6 +700,10 @@
     - warn: {lhs: if isJust x then f (fromJust x) else y, rhs: maybe y f x}
     - warn: {lhs: maybe Nothing (Just . f), rhs: fmap f}
     - hint: {lhs: map fromJust (filter isJust x), rhs:  Data.Maybe.catMaybes x}
+    - hint: {lhs: filter isJust (map f x), rhs: map Just (mapMaybe f x), name: Use mapMaybe}
+    - hint: {lhs: filter isJust (f <*> x), rhs: map Just (mapMaybe f x), name: Use mapMaybe}
+    - hint: {lhs: filter isJust (x <&> f), rhs: map Just (mapMaybe f x), name: Use mapMaybe}
+    - hint: {lhs: filter isJust (fmap f x), rhs: map Just (mapMaybe f x), name: Use mapMaybe}
     - warn: {lhs: x == Nothing , rhs:  isNothing x}
     - warn: {lhs: Nothing == x , rhs:  isNothing x}
     - warn: {lhs: x /= Nothing , rhs:  Data.Maybe.isJust x}
@@ -664,23 +714,30 @@
     - warn: {lhs: if isNothing x then y else fromJust x, rhs: fromMaybe y x}
     - warn: {lhs: if isJust x then fromJust x else y, rhs: fromMaybe y x}
     - warn: {lhs: isJust x && (fromJust x == y), rhs: x == Just y}
+    - warn: {lhs: isJust y && (x == fromJust y), rhs: Just x == y}
     - warn: {lhs: mapMaybe f (map g x), rhs: mapMaybe (f . g) x, name: Fuse mapMaybe/map}
     - warn: {lhs: fromMaybe a (fmap f x), rhs: maybe a f x}
     - warn: {lhs: fromMaybe a (f <$> x), rhs: maybe a f x}
+    - warn: {lhs: fromMaybe a (x <&> f), rhs: maybe a f x}
     - warn: {lhs: mapMaybe id, rhs: catMaybes}
     - hint: {lhs: "[x | Just x <- a]", rhs: Data.Maybe.catMaybes a, side: isVar x}
     - hint: {lhs: case m of Nothing -> Nothing; Just x -> x, rhs: Control.Monad.join m}
     - hint: {lhs: maybe Nothing id, rhs: join}
     - hint: {lhs: maybe Nothing f x, rhs: f =<< x}
-    - warn: {lhs: maybe x f (g <$> y), rhs: maybe x (f . g) y, name: Redundant fmap}
+    - warn: {lhs: maybe x f (g <$> y), rhs: maybe x (f . g) y, name: Redundant <$>}
+    - warn: {lhs: maybe x f (y <&> g), rhs: maybe x (f . g) y, name: Redundant <&>}
     - warn: {lhs: maybe x f (fmap g y), rhs: maybe x (f . g) y, name: Redundant fmap}
     - warn: {lhs: isJust (f <$> x), rhs: isJust x}
+    - warn: {lhs: isJust (x <&> f), rhs: isJust x}
     - warn: {lhs: isJust (fmap f x), rhs: isJust x}
     - warn: {lhs: isNothing (f <$> x), rhs: isNothing x}
+    - warn: {lhs: isNothing (x <&> f), rhs: isNothing x}
     - warn: {lhs: isNothing (fmap f x), rhs: isNothing x}
     - warn: {lhs: fromJust (f <$> x), rhs: f (fromJust x), note: IncreasesLaziness}
+    - warn: {lhs: fromJust (x <&> f), rhs: f (fromJust x), note: IncreasesLaziness}
     - warn: {lhs: fromJust (fmap f x), rhs: f (fromJust x), note: IncreasesLaziness}
-    - warn: {lhs: mapMaybe f (g <$> x), rhs: mapMaybe (f . g) x, name: Redundant fmap}
+    - warn: {lhs: mapMaybe f (g <$> x), rhs: mapMaybe (f . g) x, name: Redundant <$>}
+    - warn: {lhs: mapMaybe f (x <&> g), rhs: mapMaybe (f . g) x, name: Redundant <&>}
     - warn: {lhs: mapMaybe f (fmap g x), rhs: mapMaybe (f . g) x, name: Redundant fmap}
     - warn: {lhs: catMaybes (nub x), rhs: nub (catMaybes x), name: Move nub out}
     - warn: {lhs: lefts (nub x), rhs: nub (lefts x), name: Move nub out}
@@ -702,10 +759,20 @@
     - warn: {lhs: "[a | Right a <- b]", rhs: rights b, side: isVar a}
     - warn: {lhs: either Left (Right . f), rhs: fmap f}
     - warn: {lhs: either f g (fmap h x), rhs: either f (g . h) x, name: Redundant fmap}
+    - warn: {lhs: either f g (h <$> x), rhs: either f (g . h) x, name: Redundant <$>}
+    - warn: {lhs: either f g (x <&> h), rhs: either f (g . h) x, name: Redundant <&>}
     - warn: {lhs: isLeft (fmap f x), rhs: isLeft x}
+    - warn: {lhs: isLeft (f <$> x), rhs: isLeft x}
+    - warn: {lhs: isLeft (x <&> f), rhs: isLeft x}
     - warn: {lhs: isRight (fmap f x), rhs: isRight x}
+    - warn: {lhs: isRight (f <$> x), rhs: isRight x}
+    - warn: {lhs: isRight (x <&> f), rhs: isRight x}
     - warn: {lhs: fromLeft x (fmap f y), rhs: fromLeft x y}
+    - warn: {lhs: fromLeft x (f <$> y), rhs: fromLeft x y}
+    - warn: {lhs: fromLeft x (y <&> f), rhs: fromLeft x y}
     - warn: {lhs: fromRight x (fmap f y), rhs: either (const x) f y}
+    - warn: {lhs: fromRight x (f <$> y), rhs: either (const x) f y}
+    - warn: {lhs: fromRight x (y <&> f), rhs: either (const x) f y}
     - warn: {lhs: either (const x) id, rhs: fromRight x}
     - warn: {lhs: either id (const x), rhs: fromLeft x}
     - warn: {lhs: either Left f x, rhs: f =<< x}
@@ -790,23 +857,59 @@
 
     # FOLDABLE
 
-    - warn: {lhs: case m of Nothing -> pure (); Just x -> f x, rhs: Data.Foldable.forM_ m f}
+    - warn: {lhs: case m of Nothing -> pure (); Just x -> f x, rhs: Data.Foldable.for_ m f}
     - warn: {lhs: case m of Nothing -> return (); Just x -> f x, rhs: Data.Foldable.forM_ m f}
-    - warn: {lhs: case m of Just x -> f x; Nothing -> pure (), rhs: Data.Foldable.forM_ m f}
+    - warn: {lhs: case m of Just x -> f x; Nothing -> pure (), rhs: Data.Foldable.for_ m f}
     - warn: {lhs: case m of Just x -> f x; Nothing -> return (), rhs: Data.Foldable.forM_ m f}
-    - warn: {lhs: case m of Just x -> f x; _ -> pure (), rhs: Data.Foldable.forM_ m f}
+    - warn: {lhs: case m of Just x -> f x; _ -> pure (), rhs: Data.Foldable.for_ m f}
     - warn: {lhs: case m of Just x -> f x; _ -> return (), rhs: Data.Foldable.forM_ m f}
-    - warn: {lhs: when (isJust m) (f (fromJust m)), rhs: Data.Foldable.forM_ m f}
+    - warn: {lhs: when (isJust m) (f (fromJust m)), rhs: Data.Foldable.for_ m f}
+    - hint: {lhs: concatMap f (fmap g x), rhs: concatMap (f . g) x, name: Fuse concatMap/fmap}
+    - hint: {lhs: concatMap f (g <$> x), rhs: concatMap (f . g) x, name: Fuse concatMap/<$>}
+    - hint: {lhs: concatMap f (x <&> g), rhs: concatMap (f . g) x, name: Fuse concatMap/<&>}
+    - warn: {lhs: null (concatMap f x), rhs: all (null . f) x}
+    - warn: {lhs: or (concat x), rhs: any or x}
+    - warn: {lhs: or (concatMap f x), rhs: any (or . f) x}
+    - warn: {lhs: and (concat x), rhs: all and x}
+    - warn: {lhs: and (concatMap f x), rhs: all (and . f) x}
+    - warn: {lhs: any f (concat x), rhs: any (any f) x}
+    - warn: {lhs: any f (concatMap g x), rhs: any (any f . g) x}
+    - warn: {lhs: all f (concat x), rhs: all (all f) x}
+    - warn: {lhs: all f (concatMap g x), rhs: all (all f . g) x}
+    - warn: {lhs: fold (concatMap f x), rhs: foldMap (fold . f) x}
+    - warn: {lhs: foldMap f (concatMap g x), rhs: foldMap (foldMap f . g) x}
+    - warn: {lhs: catMaybes (concatMap f x), rhs: concatMap (catMaybes . f) x, name: Move concatMap out}
+    - hint: {lhs: filter f (concatMap g x), rhs: concatMap (filter f . g) x, name: Move concatMap out}
+    - warn: {lhs: mapMaybe f (concatMap g x), rhs: concatMap (mapMaybe f . g) x, name: Move concatMap out}
+    - warn: {lhs: or (fmap p x), rhs: any p x}
+    - warn: {lhs: or (p <$> x), rhs: any p x}
+    - warn: {lhs: or (x <&> p), rhs: any p x}
+    - warn: {lhs: and (fmap p x), rhs: all p x}
+    - warn: {lhs: and (p <$> x), rhs: all p x}
+    - warn: {lhs: and (x <&> p), rhs: all p x}
+    - warn: {lhs: any f (fmap g x), rhs: any (f . g) x}
+    - warn: {lhs: any f (g <$> x), rhs: any (f . g) x}
+    - warn: {lhs: any f (x <&> g), rhs: any (f . g) x}
+    - warn: {lhs: all f (fmap g x), rhs: all (f . g) x}
+    - warn: {lhs: all f (g <$> x), rhs: all (f . g) x}
+    - warn: {lhs: all f (x <&> g), rhs: all (f . g) x}
+    - hint: {lhs: foldr f z (fmap g x), rhs: foldr (f . g) z x, name: Fuse foldr/fmap}
+    - hint: {lhs: foldr f z (g <$> x), rhs: foldr (f . g) z x, name: Fuse foldr/<$>}
+    - hint: {lhs: foldr f z (x <&> g), rhs: foldr (f . g) z x, name: Fuse foldr/<&>}
 
     # STATE MONAD
 
     - warn: {lhs: f <$> Control.Monad.State.get, rhs: gets f}
+    - warn: {lhs: Control.Monad.State.get <&> f, rhs: gets f}
     - warn: {lhs: fmap f  Control.Monad.State.get, rhs: gets f}
     - warn: {lhs: f <$> Control.Monad.State.gets g, rhs: gets (f . g)}
+    - warn: {lhs: Control.Monad.State.gets g <&> f, rhs: gets (f . g)}
     - warn: {lhs: fmap f (Control.Monad.State.gets g), rhs: gets (f . g)}
     - warn: {lhs: f <$> Control.Monad.Reader.ask, rhs: asks f}
+    - warn: {lhs: Control.Monad.Reader.ask <&> f, rhs: asks f}
     - warn: {lhs: fmap f Control.Monad.Reader.ask, rhs: asks f}
     - warn: {lhs: f <$> Control.Monad.Reader.asks g, rhs: asks (f . g)}
+    - warn: {lhs: Control.Monad.Reader.asks g <&> f, rhs: asks (f . g)}
     - warn: {lhs: fmap f (Control.Monad.Reader.asks g), rhs: asks (f . g)}
     - warn: {lhs: fst (runState m s), rhs: evalState m s}
     - warn: {lhs: snd (runState m s), rhs: execState m s}
@@ -825,6 +928,14 @@
     - warn: {lhs: either f g (Right y), rhs: g y, name: Evaluate}
     - warn: {lhs: "fst (x,y)", rhs: x, name: Evaluate}
     - warn: {lhs: "snd (x,y)", rhs: "y", name: Evaluate}
+    - warn: {lhs: fromJust (Just x), rhs: x, name: Evaluate}
+    - warn: {lhs: fromLeft y (Left x), rhs: x, name: Evaluate}
+    - warn: {lhs: fromLeft y (Right x), rhs: "y", name: Evaluate}
+    - warn: {lhs: fromRight y (Right x), rhs: x, name: Evaluate}
+    - warn: {lhs: fromRight y (Left x), rhs: "y", name: Evaluate}
+    - warn: {lhs: "head [x]", rhs: "x", name: Evaluate}
+    - warn: {lhs: "last [x]", rhs: "x", name: Evaluate}
+    - warn: {lhs: "tail [x]", rhs: "[]", name: Evaluate}
     - warn: {lhs: "init [x]", rhs: "[]", name: Evaluate}
     - warn: {lhs: "null [x]", rhs: "False", name: Evaluate}
     - warn: {lhs: "null []", rhs: "True", name: Evaluate}
@@ -855,6 +966,8 @@
     - warn: {lhs: x / 1, rhs: x, name: Evaluate}
     - warn: {lhs: "concat [a]", rhs: a, name: Evaluate}
     - warn: {lhs: "concat []", rhs: "[]", name: Evaluate}
+    - warn: {lhs: "concatMap f [a]", rhs: f a, name: Evaluate}
+    - warn: {lhs: "concatMap f []", rhs: "[]", name: Evaluate}
     - warn: {lhs: "zip [] []", rhs: "[]", name: Evaluate}
     - warn: {lhs: const x y, rhs: x, name: Evaluate}
     - warn: {lhs: any (const False), rhs: const False, note: IncreasesLaziness, name: Evaluate}
@@ -886,9 +999,11 @@
     - warn: {lhs: "toList      (x,b)", rhs: b, name: Using toList on tuple}
     - warn: {lhs: "maximum     (x,b)", rhs: b, name: Using maximum on tuple}
     - warn: {lhs: "minimum     (x,b)", rhs: b, name: Using minimum on tuple}
+    - warn: {lhs: "notElem e   (x,b)", rhs: e /= b, name: Using notElem on tuple}
     - warn: {lhs: "sum         (x,b)", rhs: b, name: Using sum on tuple}
     - warn: {lhs: "product     (x,b)", rhs: b, name: Using product on tuple}
     - warn: {lhs: "concat      (x,b)", rhs: b, name: Using concat on tuple}
+    - warn: {lhs: "concatMap f (x,b)", rhs: f b, name: Using concatMap on tuple}
     - warn: {lhs: "and         (x,b)", rhs: b, name: Using and on tuple}
     - warn: {lhs: "or          (x,b)", rhs: b, name: Using or on tuple}
     - warn: {lhs: "any     f   (x,b)", rhs: f b, name: Using any on tuple}
@@ -906,9 +1021,11 @@
     - warn: {lhs: "toList      (x,y,b)", rhs: b, name: Using toList on tuple}
     - warn: {lhs: "maximum     (x,y,b)", rhs: b, name: Using maximum on tuple}
     - warn: {lhs: "minimum     (x,y,b)", rhs: b, name: Using minimum on tuple}
+    - warn: {lhs: "notElem e   (x,y,b)", rhs: e /= b, name: Using notElem on tuple}
     - warn: {lhs: "sum         (x,y,b)", rhs: b, name: Using sum on tuple}
     - warn: {lhs: "product     (x,y,b)", rhs: b, name: Using product on tuple}
     - warn: {lhs: "concat      (x,y,b)", rhs: b, name: Using concat on tuple}
+    - warn: {lhs: "concatMap f (x,y,b)", rhs: f b, name: Using concatMap on tuple}
     - warn: {lhs: "and         (x,y,b)", rhs: b, name: Using and on tuple}
     - warn: {lhs: "or          (x,y,b)", rhs: b, name: Using or on tuple}
     - warn: {lhs: "any     f   (x,y,b)", rhs: f b, name: Using any on tuple}
@@ -1041,16 +1158,114 @@
     - hint: {lhs: "\\(x, y) -> [x, y]", rhs: Data.Bifoldable.biList, note: IncreasesLaziness}
     - hint: {lhs: const mempty, rhs: mempty}
     - hint: {lhs: \x -> mempty, rhs: mempty, name: Redundant lambda}
+    - warn: {lhs: map f x >>= g, rhs: x >>= g . f}
+    - warn: {lhs: g =<< map f x, rhs: g . f =<< x}
+    - hint: {lhs: join (map f x), rhs: f =<< x}
+    - warn: {lhs: map unzip (mapM f x), rhs: Control.Monad.mapAndUnzipM f x}
 
+# Warn on partial functions whose use can be avoided relatively easily.
+# These functions are in the base package, excluding IO and GHC modules.
+- group:
+    name: partial
+    enabled: false
+    imports:
+    - package base
+    rules:
+
+    # Data.Bifoldable
+
+    - warn: {lhs: bifoldr1, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: bifoldl1, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: bimaximum, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: biminimum, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: bimaximumBy, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: biminimumBy, rhs: undefined, name: Avoid partial function}
+
+    # Data.Bits
+
+    - warn: {lhs: bitSize x, rhs: "case bitSizeMaybe x of Just n -> n; Nothing -> error _", name: Avoid partial function}
+    - warn: {lhs: shiftL x b, rhs: shift x b, name: Avoid partial function}
+    - warn: {lhs: shiftR x b, rhs: shift x (-b), name: Avoid partial function}
+    - warn: {lhs: unsafeShiftL x b, rhs: shift x b, name: Avoid partial function}
+    - warn: {lhs: unsafeShiftR x b, rhs: shift x (-b), name: Avoid partial function}
+    - warn: {lhs: rotateL x b, rhs: rotate x b, name: Avoid partial function}
+    - warn: {lhs: rotateR x b, rhs: rotate x (-b), name: Avoid partial function}
+
+    # Data.Foldable
+
+    - warn: {lhs: foldr1, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: foldl1, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: maximum, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: minimum, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: maximumBy, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: minimumBy, rhs: undefined, name: Avoid partial function}
+
+    # Data.List
+
+    - warn: {lhs: head l, rhs: "case l of x:_ -> x; [] -> error _", side: not (isNonEmpty l), name: Avoid partial function}
+    - warn: {lhs: last l, rhs: "case reverse l of x:_ -> x; [] -> error _", side: not (isNonEmpty l), name: Avoid partial function}
+    - warn: {lhs: tail l, rhs: "case l of _:xs -> xs; [] -> error _", side: not (isNonEmpty x), name: Avoid partial function}
+    - warn: {lhs: init l, rhs: "case reverse l of _:xs -> reverse xs; [] -> error _", side: not (isNonEmpty x), name: Avoid partial function}
+    - warn: {lhs: l !! n, rhs: "case drop n l of x:_ -> x; [] -> error _", name: Avoid partial function}
+
+    # Data.List.NonEmpty
+
+    - warn: {lhs: Data.List.NonEmpty.fromList l, rhs: "case nonEmpty l of Just xs -> xs; Nothing -> error _", name: Avoid partial function}
+
+    # Data.Maybe
+
+    - warn: {lhs: fromJust v, rhs: "case v of Just x -> x; Nothing -> error _", name: Avoid partial function}
+
+# Strictly warn even on partial functions in the base package whose use
+# are almost unavoidable for their functionality.
+- group:
+    name: partial-strict
+    enabled: false
+    imports:
+    - package base
+    rules:
+
+    # Data.Char
+
+    - warn: {lhs: digitToInt, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: intToDigit, rhs: undefined, name: Avoid partial function}
+
+    # Data.Fixed
+
+    - warn: {lhs: div', rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: mod', rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: divMod', rhs: undefined, name: Avoid partial function}
+
+    # Data.List
+
+    - warn: {lhs: cycle, rhs: undefined, name: Avoid partial function}
+
+    # Data.Ratio
+
+    - warn: {lhs: x % y, rhs: undefined, name: Avoid partial function}
+
+    # Prelude
+
+    - warn: {lhs: succ, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: pred, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: toEnum, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: fromEnum, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: quot, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: rem, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: div, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: mod, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: quotRem, rhs: undefined, name: Avoid partial function}
+    - warn: {lhs: divMod, rhs: undefined, name: Avoid partial function}
+
 # hints that use the 'extra' library
 - group:
     name: extra
     enabled: false
     rules:
     - warn: {lhs: fmap concat (forM a b), rhs: concatForM a b}
+    - warn: {lhs: map concat (forM a b), rhs: concatForM a b}
     - warn: {lhs: concat <$> forM a b, rhs: concatForM a b}
-    - warn: {lhs: fmap concat (forM_ a b), rhs: concatForM_ a b}
-    - warn: {lhs: concat <$> forM_ a b, rhs: concatForM_ a b}
+    - warn: {lhs: forM a b <&> concat, rhs: concatForM a b}
     - warn: {lhs: "maybe (pure ()) b a", rhs: "whenJust a b"}
     - warn: {lhs: "maybe (return ()) b a", rhs: "whenJust a b"}
     - warn: {lhs: "maybeM (pure ()) b a", rhs: "whenJustM a b"}
@@ -1095,7 +1310,11 @@
     - warn: {lhs: "map toUpper", rhs: "upper"}
     - warn: {lhs: "mergeBy compare", rhs: "merge"}
     - warn: {lhs: "breakEnd (not . a)", rhs: "spanEnd a"}
+    - warn: {lhs: "breakEnd notNull", rhs: "spanEnd null", name: Use spanEnd}
+    - warn: {lhs: "breakEnd (notElem x)", rhs: "spanEnd (elem x)", name: Use spanEnd}
     - warn: {lhs: "spanEnd (not . a)", rhs: "breakEnd a"}
+    - warn: {lhs: "spanEnd notNull", rhs: "breakEnd null", name: Use breakEnd}
+    - warn: {lhs: "spanEnd (notElem x)", rhs: "breakEnd (elem x)", name: Use breakEnd}
     - warn: {lhs: "mconcat (map a b)", rhs: "mconcatMap a b"}
     - warn: {lhs: "fromMaybe b (stripPrefix a b)", rhs: "dropPrefix a b"}
     - warn: {lhs: "fromMaybe b (stripSuffix a b)", rhs: "dropSuffix a b"}
@@ -1110,15 +1329,29 @@
     - warn: {lhs: "readFileEncoding' utf8", rhs: "readFileUTF8'"}
     - warn: {lhs: "withBinaryFile a ReadMode hGetContents'", rhs: "readFileBinary' a"}
     - warn: {lhs: "writeFileEncoding utf8", rhs: "writeFileUTF8"}
-    - warn: {lhs: "head $ x ++ [y]", rhs: "headDef y x"}
-    - warn: {lhs: "last $ x : y", rhs: "lastDef x y"}
+    - warn: {lhs: "head (x ++ [y])", rhs: "headDef y x"}
+    - warn: {lhs: "last (x : y)", rhs: "lastDef x y"}
     - warn: {lhs: "drop 1", rhs: "drop1"}
     - warn: {lhs: "dropEnd 1", rhs: "dropEnd1"}
+    - warn: {lhs: span notNull, rhs: break null, name: Use break}
+    - warn: {lhs: break notNull, rhs: span null, name: Use span}
+    - warn: {lhs: when (notNull x), rhs: unless (null x), name: Use unless}
+    - warn: {lhs: unless (notNull x), rhs: when (null x), name: Use when}
+    - warn: {lhs: not (notNull x), rhs: null x}
     - warn: {lhs: notNull (concat x), rhs: any notNull x}
+    - warn: {lhs: notNull (concatMap f x), rhs: any (notNull . f) x}
     - warn: {lhs: notNull (filter f x), rhs: any f x}
     - warn: {lhs: "notNull [x]", rhs: "True", name: Evaluate}
     - warn: {lhs: "notNull []", rhs: "False", name: Evaluate}
+    - warn: {lhs: "notNull \"\"", rhs: "False", name: Evaluate}
     - hint: {lhs: "\\(x,y) -> (f x, f y)", rhs: both f}
+    - warn: {lhs: fromLeft' (Left x), rhs: x, name: Evaluate}
+    - warn: {lhs: fromRight' (Right x), rhs: x, name: Evaluate}
+    - warn: {lhs: fromEither (Left x), rhs: x, name: Evaluate}
+    - warn: {lhs: fromEither (Right x), rhs: x, name: Evaluate}
+    - hint: {lhs: nub (sort x), rhs: nubSort x}
+    - warn: {lhs: sort (nub x), rhs: nubSort x}
+    - warn: {lhs: notNull x, rhs: "True", side: isTuple x, name: Using notNull on tuple}
 
 # hints that will be enabled in future
 - group:
@@ -1267,6 +1500,8 @@
 # yes = a & (mapped . b) %~ c -- a <&> b %~ c
 # test a = foo (\x -> True) -- const True
 # test a = foo (\_ -> True) -- const True
+# {-# LANGUAGE NamedFieldPuns #-}; data Foo = Foo {foo :: Int}; issue1430_ctor x = f (\foo-> Foo{foo})
+# {-# LANGUAGE NamedFieldPuns #-}; data Foo = Foo {foo :: Int}; issue1430_update x = f (\foo -> x{foo})
 # test a = foo (\x -> x) -- id
 # h a = flip f x (y z) -- f (y z) x
 # h a = flip f x $ y z
@@ -1420,7 +1655,9 @@
 # main = hello .~ Just 12 -- hello ?~ 12
 # foo = liftIO $ window `on` deleteEvent $ do a; b
 # no = sort <$> f input `shouldBe` sort <$> x
-# sortBy (comparing length) -- sortOn length
+# no = sortBy (comparing Down)
+# yes = sortBy (flip (comparing f)) -- sortBy (comparing (Data.Ord.Down . f))
+# yes = reverse (sort x) -- sortBy (comparing Data.Ord.Down) x
 # myJoin = on $ child ^. ChildParentId ==. parent ^. ParentId
 # foo = typeOf (undefined :: Foo Int) -- typeRep (Proxy :: Proxy (Foo Int))
 # foo = typeOf (undefined :: a) -- typeRep (Proxy :: Proxy a)
diff --git a/hlint.cabal b/hlint.cabal
--- a/hlint.cabal
+++ b/hlint.cabal
@@ -1,13 +1,13 @@
 cabal-version:      1.18
 build-type:         Simple
 name:               hlint
-version:            3.5
+version:            3.6
 license:            BSD3
 license-file:       LICENSE
 category:           Development
 author:             Neil Mitchell <ndmitchell@gmail.com>
 maintainer:         Neil Mitchell <ndmitchell@gmail.com>
-copyright:          Neil Mitchell 2006-2022
+copyright:          Neil Mitchell 2006-2023
 synopsis:           Source code suggestions
 description:
     HLint gives suggestions on how to improve your source code.
@@ -36,7 +36,7 @@
 extra-doc-files:
     README.md
     CHANGES.txt
-tested-with:        GHC==9.2, GHC==9.0
+tested-with:        GHC==9.6, GHC==9.4, GHC==9.2
 
 source-repository head
     type:     git
@@ -72,7 +72,7 @@
         utf8-string,
         data-default >= 0.3,
         cpphs >= 1.20.1,
-        cmdargs >= 0.10,
+        cmdargs >= 0.10.22,
         uniplate >= 1.5,
         ansi-terminal >= 0.8.1,
         extra >= 1.7.3,
@@ -81,16 +81,16 @@
         deriving-aeson >= 0.2,
         filepattern >= 0.1.1
 
-    if !flag(ghc-lib) && impl(ghc >= 9.4.1) && impl(ghc < 9.5.0)
+    if !flag(ghc-lib) && impl(ghc >= 9.6.1) && impl(ghc < 9.7.0)
       build-depends:
-        ghc == 9.4.*,
+        ghc == 9.6.*,
         ghc-boot-th,
         ghc-boot
     else
       build-depends:
-          ghc-lib-parser == 9.4.*
+          ghc-lib-parser == 9.6.*
     build-depends:
-        ghc-lib-parser-ex >= 9.4.0.0 && < 9.4.1
+        ghc-lib-parser-ex >= 9.6.0.0 && < 9.6.1
 
     if flag(gpl)
         build-depends: hscolour >= 1.21
@@ -124,6 +124,7 @@
         Timing
         CC
         EmbedData
+        SARIF
         Summary
         Config.Compute
         Config.Haskell
@@ -170,7 +171,7 @@
         Test.Annotations
         Test.InputOutput
         Test.Util
-    ghc-options: -Wunused-binds -Wunused-imports -Worphans
+    ghc-options: -Wunused-binds -Wunused-imports -Worphans -Wprepositive-qualified-module
 
 
 executable hlint
diff --git a/src/Apply.hs b/src/Apply.hs
--- a/src/Apply.hs
+++ b/src/Apply.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 
 module Apply(applyHints, applyHintFile, applyHintFiles) where
 
@@ -18,9 +19,10 @@
 import GHC.Types.SrcLoc
 import GHC.Hs
 import Language.Haskell.GhclibParserEx.GHC.Hs
-import qualified Data.HashSet as Set
+import Data.HashSet qualified as Set
 import Prelude
 import Util
+import Timing
 
 
 -- | Apply hints to a single file, you may have the contents of the file.
@@ -29,14 +31,14 @@
     res <- parseModuleApply flags s file src
     pure $ case res of
         Left err -> [err]
-        Right m -> executeHints s [m]
+        Right m -> timed "Execute hints" file (forceList $ executeHints s [m])
 
 
 -- | Apply hints to multiple files, allowing cross-file hints to fire.
 applyHintFiles :: ParseFlags -> [Setting] -> [FilePath] -> IO [Idea]
 applyHintFiles flags s files = do
     (err, ms) <- partitionEithers <$> mapM (\file -> parseModuleApply flags s file Nothing) files
-    pure $ err ++ executeHints s ms
+    pure $ err ++ timed "Execute hints" "all modules" (forceList $ executeHints s ms)
 
 
 -- | Given a way of classifying results, and a 'Hint', apply to a set of modules generating a list of 'Idea's.
@@ -72,7 +74,7 @@
 removeRequiresExtensionNotes :: ModuleEx -> Idea -> Idea
 removeRequiresExtensionNotes m = \x -> x{ideaNote = filter keep $ ideaNote x}
     where
-        exts = Set.fromList $ concatMap snd $ languagePragmas $ pragmas (comments (hsmodAnn (unLoc . ghcModule $ m)))
+        exts = Set.fromList $ concatMap snd $ languagePragmas $ pragmas (comments (hsmodAnn (hsmodExt . unLoc . ghcModule $ m)))
         keep (RequiresExtension x) = not $ x `Set.member` exts
         keep _ = True
 
diff --git a/src/CC.hs b/src/CC.hs
--- a/src/CC.hs
+++ b/src/CC.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
 -- |
@@ -14,13 +15,13 @@
 import Data.Char (toUpper)
 import Data.Text (Text)
 
-import qualified Data.Text as T
-import qualified Data.ByteString.Lazy.Char8 as C8
+import Data.Text qualified as T
+import Data.ByteString.Lazy.Char8 qualified as C8
 
 import Idea (Idea(..), Severity(..))
 
-import qualified GHC.Types.SrcLoc as GHC
-import qualified GHC.Util as GHC
+import GHC.Types.SrcLoc qualified as GHC
+import GHC.Util qualified as GHC
 
 data Issue = Issue
     { issueType :: Text
diff --git a/src/CmdLine.hs b/src/CmdLine.hs
--- a/src/CmdLine.hs
+++ b/src/CmdLine.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost, CPP #-}
 {-# LANGUAGE PatternGuards, DeriveDataTypeable, TupleSections #-}
 {-# OPTIONS_GHC -Wno-missing-fields -fno-cse -O0 #-}
 
@@ -9,7 +10,7 @@
 
 import Control.Monad.Extra
 import Control.Exception.Extra
-import qualified Data.ByteString as BS
+import Data.ByteString qualified as BS
 import Data.Char
 import Data.List.Extra
 import Data.Maybe
@@ -20,7 +21,7 @@
 import GHC.Driver.Session hiding (verbosity)
 
 import Language.Preprocessor.Cpphs
-import System.Console.ANSI(hSupportsANSIWithoutEmulation)
+import System.Console.ANSI(hSupportsANSI)
 import System.Console.CmdArgs.Explicit(helpText, HelpFormat(..))
 import System.Console.CmdArgs.Implicit
 import System.Directory.Extra
@@ -84,7 +85,7 @@
 data ColorMode
     = Never  -- ^ Terminal output will never be coloured.
     | Always -- ^ Terminal output will always be coloured.
-    | Auto   -- ^ Terminal output will be coloured if $TERM and stdout appear to support it.
+    | Auto   -- ^ Terminal output will be coloured if $TERM and stdout appear to support it, and NO_COLOR is not set.
       deriving (Show, Typeable, Data)
 
 
@@ -96,13 +97,14 @@
     = CmdMain
         {cmdFiles :: [FilePath]    -- ^ which files to run it on, nothing = none given
         ,cmdReports :: [FilePath]        -- ^ where to generate reports
-        ,cmdGivenHints :: [FilePath]     -- ^ which settignsfiles were explicitly given
+        ,cmdGivenHints :: [FilePath]     -- ^ which settings files were explicitly given
         ,cmdWithGroups :: [String]       -- ^ groups that are given on the command line
         ,cmdGit :: Bool                  -- ^ use git ls-files to find files
         ,cmdColor :: ColorMode           -- ^ color the result
-        ,cmdThreads :: Int              -- ^ Numbmer of threads to use, 0 = whatever GHC has
+        ,cmdThreads :: Int              -- ^ Number of threads to use, 0 = whatever GHC has
         ,cmdIgnore :: [String]           -- ^ the hints to ignore
         ,cmdShowAll :: Bool              -- ^ display all skipped items
+        ,cmdIgnoreSuggestions :: Bool    -- ^ ignore suggestions
         ,cmdExtension :: [String]        -- ^ extensions
         ,cmdLanguage :: [String]      -- ^ the extensions (may be prefixed by "No")
         ,cmdCross :: Bool                -- ^ work between source files, applies to hints such as duplicate code between modules
@@ -117,6 +119,7 @@
         ,cmdCppAnsi :: Bool
         ,cmdJson :: Bool                -- ^ display hint data as JSON
         ,cmdCC :: Bool                  -- ^ display hint data as Code Climate Issues
+        ,cmdSARIF :: Bool               -- ^ display hint data as SARIF
         ,cmdNoSummary :: Bool           -- ^ do not show the summary info
         ,cmdOnly :: [String]            -- ^ specify which hints explicitly
         ,cmdNoExitCode :: Bool
@@ -144,6 +147,7 @@
         ,cmdThreads = 1 &= name "threads" &= name "j" &= opt (0 :: Int) &= help "Number of threads to use (-j for all)"
         ,cmdIgnore = nam "ignore" &= typ "HINT" &= help "Ignore a particular hint"
         ,cmdShowAll = nam "show" &= help "Show all ignored ideas"
+        ,cmdIgnoreSuggestions = nam_ "ignore-suggestions" &= help "Ignore suggestions, only show warnings and errors"
         ,cmdExtension = nam "extension" &= typ "EXT" &= help "File extensions to search (default hs/lhs)"
         ,cmdLanguage = nam_ "language" &= name "X" &= typ "EXTENSION" &= help "Language extensions (Arrows, NoCPP)"
         ,cmdCross = nam_ "cross" &= help "Work between modules"
@@ -158,6 +162,7 @@
         ,cmdCppAnsi = nam_ "cpp-ansi" &= help "Use CPP in ANSI compatibility mode"
         ,cmdJson = nam_ "json" &= help "Display hint data as JSON"
         ,cmdCC = nam_ "cc" &= help "Display hint data as Code Climate Issues"
+        ,cmdSARIF = nam_ "sarif" &= help "Display hint data as SARIF"
         ,cmdNoSummary = nam_ "no-summary" &= help "Do not show summary information"
         ,cmdOnly = nam "only" &= typ "HINT" &= help "Specify which hints explicitly"
         ,cmdNoExitCode = nam_ "no-exit-code" &= help "Do not give a negative exit if hints"
@@ -167,7 +172,7 @@
         ,cmdRefactorOptions = nam_ "refactor-options" &= typ "OPTIONS" &= help "Options to pass to the `refactor` executable"
         ,cmdWithRefactor = nam_ "with-refactor" &= help "Give the path to refactor"
         ,cmdIgnoreGlob = nam_ "ignore-glob" &= help "Ignore paths matching glob pattern (e.g. foo/bar/*.hs)"
-        ,cmdGenerateMdSummary = nam_ "generate-summary" &= opt "hints.md" &= help "Generate a summary of available hints, in Mardown format"
+        ,cmdGenerateMdSummary = nam_ "generate-summary" &= opt "hints.md" &= help "Generate a summary of available hints, in Markdown format"
         ,cmdGenerateJsonSummary = nam_ "generate-summary-json" &= opt "hints.json" &= help "Generate a summary of available hints, in JSON format"
         ,cmdGenerateExhaustiveConf = nam_ "generate-config" &= opt Warning &= typ "LEVEL" &= help "Generate a .hlint.yaml config file with all hints set to the specified severity level (default level: warn, alternatives: ignore, suggest, error)"
         ,cmdTest = nam_ "test" &= help "Run the test suite"
@@ -177,7 +182,7 @@
                    ,"To check all Haskell files in 'src' and generate a report type:"
                    ,"  hlint src --report"]
     ] &= program "hlint" &= verbosity
-    &=  summary ("HLint v" ++ showVersion version ++ ", (C) Neil Mitchell 2006-2022")
+    &=  summary ("HLint v" ++ showVersion version ++ ", (C) Neil Mitchell 2006-2023")
     where
         nam xs = nam_ xs &= name [head xs]
         nam_ xs = def &= explicit &= name xs
@@ -219,19 +224,22 @@
         {boolopts=defaultBoolOptions{hashline=False, stripC89=True, ansi=cmdCppAnsi cmd}
         ,includes = cmdCppInclude cmd
         ,preInclude = cmdCppFile cmd
-        ,defines = ("__HLINT__","1") : [(a,drop1 b) | x <- cmdCppDefine cmd, let (a,b) = break (== '=') x]
+        ,defines = ("__HLINT__","1") : [(a,drop1 b) | x <- cmdCppDefine cmd, let (a,b) = break (== '=') x] ++ [("__GLASGOW_HASKELL__", show (__GLASGOW_HASKELL__ :: Int))]
         }
 
 
 -- | Determines whether to use colour or not.
 cmdUseColour :: Cmd -> IO Bool
-cmdUseColour cmd = case cmdColor cmd of
-  Always -> pure True
-  Never  -> pure False
-  Auto   -> do
-    supportsANSI <- hSupportsANSIWithoutEmulation stdout
-    pure $ Just True == supportsANSI
-
+cmdUseColour cmd = do
+  -- https://no-color.org
+  -- if NO_COLOR is set, regardless of value, we do not colour output.
+  noColor <- lookupEnv "NO_COLOR"
+  case cmdColor cmd of
+    Always -> pure True
+    Never  -> pure False
+    Auto   -> do
+      supportsANSI <- hSupportsANSI stdout
+      pure $ supportsANSI && isNothing noColor
 
 "." <\> x = x
 x <\> y = x </> y
diff --git a/src/Config/Haskell.hs b/src/Config/Haskell.hs
--- a/src/Config/Haskell.hs
+++ b/src/Config/Haskell.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE PatternGuards, ViewPatterns, TupleSections #-}
 module Config.Haskell(
     readPragma,
@@ -23,7 +24,7 @@
 import GHC.Data.FastString
 import GHC.Parser.Annotation
 import GHC.Utils.Outputable
-import qualified GHC.Data.Strict
+import GHC.Data.Strict qualified
 
 import Language.Haskell.GhclibParserEx.GHC.Utils.Outputable
 import Language.Haskell.GhclibParserEx.GHC.Types.Name.Reader
@@ -31,7 +32,7 @@
 -- | Read an {-# ANN #-} pragma and determine if it is intended for HLint.
 --   Return Nothing if it is not an HLint pragma, otherwise what it means.
 readPragma :: AnnDecl GhcPs -> Maybe Classify
-readPragma (HsAnnotation _ _ provenance expr) = f expr
+readPragma (HsAnnotation _ provenance expr) = f expr
     where
         name = case provenance of
             ValueAnnProvenance (L _ x) -> occNameStr x
diff --git a/src/Config/Type.hs b/src/Config/Type.hs
--- a/src/Config/Type.hs
+++ b/src/Config/Type.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DerivingVia #-}
 {-# LANGUAGE DataKinds #-}
@@ -18,7 +19,7 @@
 import Prelude
 
 
-import qualified GHC.Hs
+import GHC.Hs qualified
 import Fixity
 import GHC.Util
 import Language.Haskell.GhclibParserEx.GHC.Hs.ExtendInstances
diff --git a/src/Config/Yaml.hs b/src/Config/Yaml.hs
--- a/src/Config/Yaml.hs
+++ b/src/Config/Yaml.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE OverloadedStrings, ViewPatterns, RecordWildCards, GeneralizedNewtypeDeriving, TupleSections #-}
@@ -31,10 +32,10 @@
 import Data.List.Extra
 import Data.Tuple.Extra
 import Control.Monad.Extra
-import qualified Data.Text as T
-import qualified Data.Vector as V
-import qualified Data.ByteString.Char8 as BS
-import qualified Data.HashMap.Strict as Map
+import Data.Text qualified as T
+import Data.Vector qualified as V
+import Data.ByteString.Char8 qualified as BS
+import Data.HashMap.Strict qualified as Map
 import Data.Generics.Uniplate.DataOnly
 import GHC.All
 import Fixity
@@ -67,7 +68,7 @@
 import Data.YAML.Aeson (encode1Strict, decode1Strict)
 import Data.Aeson hiding (encode)
 import Data.Aeson.Types (Parser)
-import qualified Data.ByteString as BSS
+import Data.ByteString qualified as BSS
 
 decodeFileEither :: FilePath -> IO (Either (Pos, String) ConfigYaml)
 decodeFileEither path = decode1Strict <$> BSS.readFile path
@@ -235,7 +236,7 @@
         POk _ x -> pure x
         PFailed ps ->
           let errMsg = head . bagToList . getMessages $ GhcPsMessage <$> snd (getPsMessages ps)
-              msg = showSDoc baseDynFlags $ pprLocMsgEnvelope errMsg
+              msg = showSDoc baseDynFlags $ pprLocMsgEnvelopeDefault errMsg
           in parseFail v $ "Failed to parse " ++ msg ++ ", when parsing:\n " ++ x
 
 ---------------------------------------------------------------------
@@ -440,7 +441,7 @@
               scope'= asScope' packageMap' (map (fmap unextendInstances) groupImports)
 
 asScope' :: Map.HashMap String [LocatedA (ImportDecl GhcPs)] -> [Either String (LocatedA (ImportDecl GhcPs))] -> Scope
-asScope' packages xs = scopeCreate (HsModule EpAnnNotUsed NoLayoutInfo Nothing Nothing (concatMap f xs) [] Nothing Nothing)
+asScope' packages xs = scopeCreate (HsModule (XModulePs EpAnnNotUsed NoLayoutInfo Nothing Nothing) Nothing Nothing (concatMap f xs) [])
     where
         f (Right x) = [x]
         f (Left x) | Just pkg <- Map.lookup x packages = pkg
diff --git a/src/Extension.hs b/src/Extension.hs
--- a/src/Extension.hs
+++ b/src/Extension.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 module Extension(
   defaultExtensions,
   configExtensions,
@@ -6,9 +7,9 @@
   ) where
 
 import Data.List.Extra
-import qualified Data.Map as Map
+import Data.Map qualified as Map
 import GHC.LanguageExtensions.Type
-import qualified Language.Haskell.GhclibParserEx.GHC.Driver.Session as GhclibParserEx
+import Language.Haskell.GhclibParserEx.GHC.Driver.Session qualified as GhclibParserEx
 
 badExtensions =
   reallyBadExtensions ++
diff --git a/src/GHC/All.hs b/src/GHC/All.hs
--- a/src/GHC/All.hs
+++ b/src/GHC/All.hs
@@ -5,7 +5,7 @@
     CppFlags(..), ParseFlags(..), defaultParseFlags,
     parseFlagsAddFixities, parseFlagsSetLanguage,
     ParseError(..), ModuleEx(..),
-    parseModuleEx, createModuleEx, createModuleExWithFixities, ghcComments, modComments,
+    parseModuleEx, createModuleEx, createModuleExWithFixities, ghcComments, modComments, firstDeclComments,
     parseExpGhcWithMode, parseImportDeclGhcWithMode, parseDeclGhcWithMode,
     ) where
 
@@ -85,7 +85,7 @@
 
 -- | Result of 'parseModuleEx', representing a parsed module.
 newtype ModuleEx = ModuleEx {
-    ghcModule :: Located HsModule
+    ghcModule :: Located (HsModule GhcPs)
 }
 
 -- | Extract a complete list of all the comments in a module.
@@ -94,8 +94,15 @@
 
 -- | Extract just the list of a modules' leading comments (pragmas).
 modComments :: ModuleEx -> EpAnnComments
-modComments = comments . hsmodAnn . unLoc . ghcModule
+modComments = comments . hsmodAnn . hsmodExt . unLoc . ghcModule
 
+-- | Extract comments associated with the first declaration of a module.
+firstDeclComments :: ModuleEx -> EpAnnComments
+firstDeclComments m =
+  case hsmodDecls . unLoc . ghcModule $ m of
+        [] -> EpaCommentsBalanced [] []
+        L (SrcSpanAnn ann _) _ : _ -> comments ann
+
 -- | The error handler invoked when GHC parsing has failed.
 ghcFailOpParseModuleEx :: String
                        -> FilePath
@@ -117,7 +124,7 @@
 ghcFixitiesFromParseFlags :: ParseFlags -> [(String, GHC.Types.Fixity.Fixity)]
 ghcFixitiesFromParseFlags = map toFixity . fixities
 
--- These next two functions get called frorm 'Config/Yaml.hs' for user
+-- These next two functions get called from 'Config/Yaml.hs' for user
 -- defined hint rules.
 
 parseModeToFlags :: ParseFlags -> DynFlags
@@ -147,10 +154,10 @@
 -- | Create a 'ModuleEx' from a GHC module. It is assumed the incoming
 -- parsed module has not been adjusted to account for operator
 -- fixities (it uses the HLint default fixities).
-createModuleEx :: Located HsModule -> ModuleEx
+createModuleEx :: Located (HsModule GhcPs) -> ModuleEx
 createModuleEx = createModuleExWithFixities (map toFixity defaultFixities)
 
-createModuleExWithFixities :: [(String, Fixity)] -> Located HsModule -> ModuleEx
+createModuleExWithFixities :: [(String, Fixity)] -> Located (HsModule GhcPs) -> ModuleEx
 createModuleExWithFixities fixities ast =
   ModuleEx (applyFixities (fixitiesFromModule ast ++ fixities) ast)
 
@@ -201,7 +208,7 @@
     parseFailureErr dynFlags ppstr file str errs =
       let errMsg = head errs
           loc = errMsgSpan errMsg
-          doc = pprLocMsgEnvelope errMsg
+          doc = pprLocMsgEnvelopeDefault errMsg
       in ghcFailOpParseModuleEx ppstr file str (loc, doc)
 
 -- | Given a line number, and some source code, put bird ticks around the appropriate bit.
diff --git a/src/GHC/Util.hs b/src/GHC/Util.hs
--- a/src/GHC/Util.hs
+++ b/src/GHC/Util.hs
@@ -41,7 +41,7 @@
 import System.FilePath
 import Language.Preprocessor.Unlit
 
-fileToModule :: FilePath -> String -> DynFlags -> ParseResult (Located HsModule)
+fileToModule :: FilePath -> String -> DynFlags -> ParseResult (Located (HsModule GhcPs))
 fileToModule filename str flags =
   parseFile filename flags
     (if takeExtension filename /= ".lhs" then str else unlit filename str)
diff --git a/src/GHC/Util/ApiAnnotation.hs b/src/GHC/Util/ApiAnnotation.hs
--- a/src/GHC/Util/ApiAnnotation.hs
+++ b/src/GHC/Util/ApiAnnotation.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 
 module GHC.Util.ApiAnnotation (
     comment_, commentText, isCommentMultiline
@@ -16,7 +17,7 @@
 import Control.Applicative
 import Data.List.Extra
 import Data.Maybe
-import qualified Data.Set as Set
+import Data.Set qualified as Set
 
 trimCommentStart :: String -> String
 trimCommentStart s
@@ -64,8 +65,7 @@
 
 -- All the extensions defined to be used.
 extensions :: EpAnnComments -> Set.Set Extension
-extensions = Set.fromList . mapMaybe readExtension .
-    concatMap snd . languagePragmas . pragmas
+extensions = Set.fromList . concatMap (mapMaybe readExtension . snd) . languagePragmas . pragmas
 
 -- Utility for a case insensitive prefix strip.
 stripPrefixCI :: String -> String -> Maybe String
@@ -87,7 +87,7 @@
 
 -- Language pragmas. The first element of the
 -- pair is the (located) annotation comment that enables the
--- pragmas enumerated by he second element of the pair.
+-- pragmas enumerated by the second element of the pair.
 languagePragmas :: [(LEpaComment, String)] -> [(LEpaComment, [String])]
 languagePragmas ps =
   [(c, exts) | (c, s) <- ps
diff --git a/src/GHC/Util/Brackets.hs b/src/GHC/Util/Brackets.hs
--- a/src/GHC/Util/Brackets.hs
+++ b/src/GHC/Util/Brackets.hs
@@ -38,6 +38,8 @@
       HsUnboundVar{} -> True
       -- Technically atomic, but lots of people think it shouldn't be
       HsRecSel{} -> False
+      -- Only relevant for OverloadedRecordDot extension
+      HsGetField{} -> True
       HsOverLabel{} -> True
       HsIPVar{} -> True
       -- Note that sections aren't atoms (but parenthesized sections are).
@@ -52,7 +54,8 @@
       HsUntypedBracket{} -> True
       -- HsSplice might be $foo, where @($foo) would require brackets,
       -- but in that case the $foo is a type, so we can still mark Splice as atomic
-      HsSpliceE{} -> True
+      HsTypedSplice{} -> True
+      HsUntypedSplice{} -> True
       HsOverLit _ x | not $ isNegativeOverLit x -> True
       HsLit _ x     | not $ isNegativeLit x     -> True
       _  -> False
@@ -107,6 +110,7 @@
 instance Brackets (LocatedA (Pat GhcPs)) where
   remParen (L _ (ParPat _ _ x _)) = Just x
   remParen _ = Nothing
+
   addParen = nlParPat
 
   isAtom (L _ x) = case x of
@@ -115,7 +119,9 @@
     ListPat{} -> True
     -- This is technically atomic, but lots of people think it shouldn't be
     ConPat _ _ RecCon{} -> False
-    ConPat _ _ (PrefixCon _ []) -> True
+    -- Before we only checked args, but not type args, resulting in a
+    -- false positive for things like (Proxy @a)
+    ConPat _ _ (PrefixCon [] []) -> True
     VarPat{} -> True
     WildPat{} -> True
     SumPat{} -> True
diff --git a/src/GHC/Util/DynFlags.hs b/src/GHC/Util/DynFlags.hs
--- a/src/GHC/Util/DynFlags.hs
+++ b/src/GHC/Util/DynFlags.hs
@@ -8,7 +8,7 @@
 -- 'parsePragmasIntoDynFlags' based solely on the parse flags
 -- (and source level annotations).
 baseDynFlags :: DynFlags
-baseDynFlags = defaultDynFlags fakeSettings fakeLlvmConfig
+baseDynFlags = defaultDynFlags fakeSettings
 
 initGlobalDynFlags :: IO ()
 initGlobalDynFlags = setUnsafeGlobalDynFlags baseDynFlags
diff --git a/src/GHC/Util/FreeVars.hs b/src/GHC/Util/FreeVars.hs
--- a/src/GHC/Util/FreeVars.hs
+++ b/src/GHC/Util/FreeVars.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE TypeFamilies #-}
@@ -19,7 +20,7 @@
 import Data.Semigroup
 import Data.List.Extra
 import Data.Set (Set)
-import qualified Data.Set as Set
+import Data.Set qualified as Set
 import Prelude
 
 ( ^+ ) :: Set OccName -> Set OccName -> Set OccName
@@ -44,7 +45,7 @@
     mconcat vs = Vars (Set.unions $ map bound vs) (Set.unions $ map free vs)
 
 -- A type `a` is a model of `AllVars a` if exists a function
--- `allVars` for producing a pair of the bound and free varaiable
+-- `allVars` for producing a pair of the bound and free variable
 -- sets in a value of `a`.
 class AllVars a where
     -- | Return the variables, erring on the side of more free
@@ -52,7 +53,7 @@
     allVars :: a -> Vars
 
 -- A type `a` is a model of `FreeVars a` if exists a function
--- `freeVars` for producing a set of free varaiable of a value of
+-- `freeVars` for producing a set of free variables of a value of
 -- `a`.
 class FreeVars a where
     -- | Return the variables, erring on the side of more free
@@ -97,12 +98,27 @@
 
 instance FreeVars (LocatedA (HsExpr GhcPs)) where
   freeVars (L _ (HsVar _ x)) = Set.fromList $ unqualNames x -- Variable.
-  freeVars (L _ (HsUnboundVar _ x)) = Set.fromList [x] -- Unbound variable; also used for "holes".
+  freeVars (L _ (HsUnboundVar _ x)) = Set.fromList [rdrNameOcc x] -- Unbound variable; also used for "holes".
   freeVars (L _ (HsLam _ mg)) = free (allVars mg) -- Lambda abstraction. Currently always a single match.
   freeVars (L _ (HsLamCase _ _ MG{mg_alts=(L _ ms)})) = free (allVars ms) -- Lambda case
   freeVars (L _ (HsCase _ of_ MG{mg_alts=(L _ ms)})) = freeVars of_ ^+ free (allVars ms) -- Case expr.
   freeVars (L _ (HsLet _ _ binds _ e)) = inFree binds e -- Let (rec).
-  freeVars (L _ (HsDo _ ctxt (L _ stmts))) = free (allVars stmts) -- Do block.
+  freeVars (L _ (HsDo _ ctxt (L _ stmts))) = snd $ foldl' alg mempty stmts -- Do block.
+    where
+      alg ::
+        (Set OccName, Set OccName) ->
+        LocatedA (StmtLR GhcPs GhcPs (LocatedA (HsExpr GhcPs))) ->
+        (Set OccName, Set OccName)
+      alg (accBound0, accFree0) stmt = (accBound, accFree)
+        where
+          accBound =
+            accBound0
+              ^+ ( case stmt of
+                     L _ (BindStmt _ pat _) -> bound (allVars pat)
+                     L _ (LetStmt _ binds) -> bound (allVars binds)
+                     _ -> mempty
+                 )
+          accFree = accFree0 ^+ (free (allVars stmt) ^- accBound0)
   freeVars (L _ (RecordCon _ _ (HsRecFields flds _))) = Set.unions $ map freeVars flds -- Record construction.
   freeVars (L _ (RecordUpd _ e flds)) =
     case flds of
@@ -158,6 +174,7 @@
    freeVars o@(L _ (HsFieldBind _ _ x _)) = freeVars x
 
 instance FreeVars (LocatedA (HsFieldBind (LocatedAn NoEpAnns (AmbiguousFieldOcc GhcPs)) (LocatedA (HsExpr GhcPs)))) where
+  freeVars (L _ (HsFieldBind _ x _ True)) = Set.singleton $ rdrNameOcc $ rdrNameAmbiguousFieldOcc $ unLoc x -- a pun
   freeVars (L _ (HsFieldBind _ _ x _)) = freeVars x
 
 instance FreeVars (LocatedA (HsFieldBind (LocatedAn NoEpAnns (FieldLabelStrings GhcPs)) (LocatedA (HsExpr GhcPs)))) where
@@ -165,7 +182,7 @@
 
 instance AllVars (LocatedA (Pat GhcPs)) where
   allVars (L _ (VarPat _ (L _ x))) = Vars (Set.singleton $ rdrNameOcc x) Set.empty -- Variable pattern.
-  allVars (L _ (AsPat _  n x)) = allVars (noLocA $ VarPat noExtField n :: LocatedA (Pat GhcPs)) <> allVars x -- As pattern.
+  allVars (L _ (AsPat _  n _ x)) = allVars (noLocA $ VarPat noExtField n :: LocatedA (Pat GhcPs)) <> allVars x -- As pattern.
   allVars (L _ (ConPat _ _ (RecCon (HsRecFields flds _)))) = allVars flds
   allVars (L _ (NPlusKPat _ n _ _ _ _)) = allVars (noLocA $ VarPat noExtField n :: LocatedA (Pat GhcPs)) -- n+k pattern.
   allVars (L _ (ViewPat _ e p)) = freeVars_ e <> allVars p -- View pattern.
@@ -216,7 +233,7 @@
   allVars (L _ (PatSynBind _ PSB{})) = mempty -- Come back to it.
 
 instance AllVars (MatchGroup GhcPs (LocatedA (HsExpr GhcPs))) where
-  allVars (MG _ _alts@(L _ alts) _) = inVars (foldMap (allVars . m_pats) ms) (allVars (map m_grhss ms))
+  allVars (MG _ _alts@(L _ alts)) = inVars (foldMap (allVars . m_pats) ms) (allVars (map m_grhss ms))
     where ms = map unLoc alts
 
 instance AllVars (LocatedA (Match GhcPs (LocatedA (HsExpr GhcPs)))) where
diff --git a/src/GHC/Util/HsExpr.hs b/src/GHC/Util/HsExpr.hs
--- a/src/GHC/Util/HsExpr.hs
+++ b/src/GHC/Util/HsExpr.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE ViewPatterns, MultiParamTypeClasses, FlexibleInstances, FlexibleContexts #-}
 {-# LANGUAGE LambdaCase #-}
@@ -26,7 +27,6 @@
 import GHC.Util.FreeVars
 import GHC.Util.View
 
-import Control.Applicative
 import Control.Monad.Trans.Class
 import Control.Monad.Trans.State
 import Control.Monad.Trans.Writer.CPS
@@ -39,7 +39,7 @@
 
 import Refact (substVars, toSSA)
 import Refact.Types hiding (SrcSpan, Match)
-import qualified Refact.Types as R (SrcSpan)
+import Refact.Types qualified as R (SrcSpan)
 
 import Language.Haskell.GhclibParserEx.GHC.Hs.Pat
 import Language.Haskell.GhclibParserEx.GHC.Hs.Expr
@@ -58,7 +58,7 @@
 
 -- | @lambda [p0, p1..pn] body@ makes @\p1 p1 .. pn -> body@
 lambda :: [LPat GhcPs] -> LHsExpr GhcPs -> LHsExpr GhcPs
-lambda vs body = noLocA $ HsLam noExtField (MG noExtField (noLocA [noLocA $ Match EpAnnNotUsed LambdaExpr vs (GRHSs emptyComments [noLocA $ GRHS EpAnnNotUsed [] body] (EmptyLocalBinds noExtField))]) Generated)
+lambda vs body = noLocA $ HsLam noExtField (MG Generated (noLocA [noLocA $ Match EpAnnNotUsed LambdaExpr vs (GRHSs emptyComments [noLocA $ GRHS EpAnnNotUsed [] body] (EmptyLocalBinds noExtField))]))
 
 -- | 'paren e' wraps 'e' in parens if 'e' is non-atomic.
 paren :: LHsExpr GhcPs -> LHsExpr GhcPs
@@ -86,7 +86,7 @@
 universeApps x = x : concatMap universeApps (childrenApps x)
 
 descendAppsM :: Monad m => (LHsExpr GhcPs  -> m (LHsExpr GhcPs)) -> LHsExpr GhcPs -> m (LHsExpr GhcPs)
-descendAppsM f (L l (HsApp _ x y)) = liftA2 (\x y -> L l $ HsApp EpAnnNotUsed x y) (descendAppsM f x) (f y)
+descendAppsM f (L l (HsApp _ x y)) = (\x y -> L l $ HsApp EpAnnNotUsed x y) <$> descendAppsM f x <*> f y
 descendAppsM f x = descendM f x
 
 transformAppsM :: Monad m => (LHsExpr GhcPs -> m (LHsExpr GhcPs)) -> LHsExpr GhcPs -> m (LHsExpr GhcPs)
@@ -125,7 +125,7 @@
 simplifyExp e@(L _ (HsLet _ _ ((HsValBinds _ (ValBinds _ binds []))) _ z)) =
   -- An expression of the form, 'let x = y in z'.
   case bagToList binds of
-    [L _ (FunBind _ _ (MG _ (L _ [L _ (Match _(FunRhs (L _ x) _ _) [] (GRHSs _[L _ (GRHS _ [] y)] ((EmptyLocalBinds _))))]) _) _)]
+    [L _ (FunBind _ _ (MG _ (L _ [L _ (Match _(FunRhs (L _ x) _ _) [] (GRHSs _[L _ (GRHS _ [] y)] ((EmptyLocalBinds _))))])))]
          -- If 'x' is not in the free variables of 'y', beta-reduce to
          -- 'z[(y)/x]'.
       | occNameStr x `notElem` vars y && length [() | Unqual a <- universeBi z, a == rdrNameOcc x] <= 1 ->
@@ -242,7 +242,7 @@
   let grhs = noLocA $ GRHS EpAnnNotUsed [] e :: LGRHS GhcPs (LHsExpr GhcPs)
       grhss = GRHSs {grhssExt = emptyComments, grhssGRHSs=[grhs], grhssLocalBinds=EmptyLocalBinds noExtField}
       match = noLocA $ Match {m_ext=EpAnnNotUsed, m_ctxt=LambdaExpr, m_pats=map strToPat ss, m_grhss=grhss} :: LMatch GhcPs (LHsExpr GhcPs)
-      matchGroup = MG {mg_ext=noExtField, mg_origin=Generated, mg_alts=noLocA [match]}
+      matchGroup = MG {mg_ext=Generated, mg_alts=noLocA [match]}
   in (noLocA $ HsLam noExtField matchGroup, const [])
 
 
@@ -251,8 +251,8 @@
 replaceBranches :: LHsExpr GhcPs -> ([LHsExpr GhcPs], [LHsExpr GhcPs] -> LHsExpr GhcPs)
 replaceBranches (L l (HsIf _ a b c)) = ([b, c], \[b, c] -> L l (HsIf EpAnnNotUsed a b c))
 
-replaceBranches (L s (HsCase _ a (MG _ (L l bs) FromSource))) =
-  (concatMap f bs, \xs -> L s (HsCase EpAnnNotUsed a (MG noExtField (L l (g bs xs)) Generated)))
+replaceBranches (L s (HsCase _ a (MG FromSource (L l bs)))) =
+  (concatMap f bs, L s . HsCase EpAnnNotUsed a . MG Generated . L l . g bs)
   where
     f :: LMatch GhcPs (LHsExpr GhcPs) -> [LHsExpr GhcPs]
     f (L _ (Match _ CaseAlt _ (GRHSs _ xs _))) = [x | (L _ (GRHS _ _ x)) <- xs]
diff --git a/src/GHC/Util/Scope.hs b/src/GHC/Util/Scope.hs
--- a/src/GHC/Util/Scope.hs
+++ b/src/GHC/Util/Scope.hs
@@ -10,7 +10,6 @@
 import GHC.Hs
 import GHC.Types.SrcLoc
 import GHC.Types.SourceText
-import GHC.Unit.Module
 import GHC.Data.FastString
 import GHC.Types.Name.Reader
 import GHC.Types.Name.Occurrence
@@ -21,6 +20,7 @@
 
 import Data.List.Extra
 import Data.Maybe
+import Data.Bifunctor
 
 -- A scope is a list of import declarations.
 newtype Scope = Scope [LImportDecl GhcPs]
@@ -30,7 +30,7 @@
     show (Scope x) = unsafePrettyPrint x
 
 -- Create a 'Scope from a module's import declarations.
-scopeCreate :: HsModule -> Scope
+scopeCreate :: HsModule GhcPs -> Scope
 scopeCreate xs = Scope $ [prelude | not $ any isPrelude res] ++ res
   where
     -- Package qualifier of an import declaration.
@@ -40,13 +40,13 @@
         RawPkgQual s -> Just s
         NoRawPkgQual -> Nothing
 
-    -- The import declaraions contained by the module 'xs'.
+    -- The import declarations contained by the module 'xs'.
     res :: [LImportDecl GhcPs]
     res = [x | x <- hsmodImports xs
              , pkg x /= Just (StringLiteral NoSourceText (fsLit "hint") Nothing)
           ]
 
-    -- Mock up an import declaraion corresponding to 'import Prelude'.
+    -- Mock up an import declaration corresponding to 'import Prelude'.
     prelude :: LImportDecl GhcPs
     prelude = noLocA $ simpleImportDecl (mkModuleName "Prelude")
 
@@ -116,7 +116,7 @@
   where ms = map unLoc $ ideclName i : maybeToList (ideclAs i)
 possImport (L _ i) (L _ (Unqual x)) =
   if ideclQualified i == NotQualified
-    then maybe PossiblyImported f (ideclHiding i)
+    then maybe PossiblyImported (f . first (== EverythingBut)) (ideclImportList i)
     else NotImported
   where
     f :: (Bool, LocatedL [LIE GhcPs]) -> IsImported
@@ -137,6 +137,6 @@
     g (L _ (IEThingWith _ y _wildcard ys)) = Just $ tag `elem` unwrapName y : map unwrapName ys
     g _ = Just False
 
-    unwrapName :: LIEWrappedName RdrName -> String
+    unwrapName :: LIEWrappedName GhcPs -> String
     unwrapName x = occNameString (rdrNameOcc $ ieWrappedName (unLoc x))
 possImport _ _ = NotImported
diff --git a/src/GHC/Util/SrcLoc.hs b/src/GHC/Util/SrcLoc.hs
--- a/src/GHC/Util/SrcLoc.hs
+++ b/src/GHC/Util/SrcLoc.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 
 module GHC.Util.SrcLoc (
@@ -10,7 +11,7 @@
 import GHC.Types.SrcLoc
 import GHC.Utils.Outputable
 import GHC.Data.FastString
-import qualified GHC.Data.Strict
+import GHC.Data.Strict qualified
 
 import Data.Default
 import Data.Data
diff --git a/src/GHC/Util/Unify.hs b/src/GHC/Util/Unify.hs
--- a/src/GHC/Util/Unify.hs
+++ b/src/GHC/Util/Unify.hs
@@ -61,10 +61,10 @@
 removeParens noParens (Subst xs) = Subst $
   map (\(x, y) -> if x `elem` noParens then (x, fromParen y) else (x, y)) xs
 
--- Peform a substition.
+-- Perform a substitution.
 -- Returns (suggested replacement, (refactor template, no bracket vars)). It adds/removes brackets
 -- for both the suggested replacement and the refactor template appropriately. The "no bracket vars"
--- is a list of substituation variables which, when expanded, should have the brackets stripped.
+-- is a list of substitution variables which, when expanded, should have the brackets stripped.
 --
 -- Examples:
 --   (traverse foo (bar baz), (traverse f (x), []))
@@ -95,7 +95,7 @@
     typ :: LHsType GhcPs -> LHsType GhcPs
     -- Type variables.
     typ (L _ (HsTyVar _ _ x))
-      | Just (L _ (HsAppType _ _ (HsWC _ y))) <- lookup (rdrNameStr x) bind = y
+      | Just (L _ (HsAppType _ _ _ (HsWC _ y))) <- lookup (rdrNameStr x) bind = y
     typ x = x :: LHsType GhcPs
 
 
@@ -114,30 +114,29 @@
     | Just (x, y) <- cast (x, y) = if (x :: FastString) == y then Just mempty else Nothing
 
     -- We need some type magic to reduce this.
-    | Just (x :: EpAnn AnnsModule) <- cast x = Just mempty
-    | Just (x :: EpAnn NameAnn) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnListItem) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnList) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnPragma) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnContext) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnParen) <- cast x = Just mempty
     | Just (x :: EpAnn Anchor) <- cast x = Just mempty
-    | Just (x :: EpAnn NoEpAnns) <- cast x = Just mempty
-    | Just (x :: EpAnn GrhsAnn) <- cast x = Just mempty
-    | Just (x :: EpAnn [AddEpAnn]) <- cast x = Just mempty
-    | Just (x :: EpAnn EpAnnHsCase) <- cast x = Just mempty
-    | Just (x :: EpAnn EpAnnUnboundVar) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnContext) <- cast x = Just mempty
     | Just (x :: EpAnn AnnExplicitSum) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnFieldLabel) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnList) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnListItem) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnParen) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnPragma) <- cast x = Just mempty
     | Just (x :: EpAnn AnnProjection) <- cast x = Just mempty
-    | Just (x :: EpAnn Anchor) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnsIf) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnSig) <- cast x = Just mempty
+    | Just (x :: EpAnn AnnsModule) <- cast x = Just mempty
     | Just (x :: EpAnn EpaLocation) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnFieldLabel) <- cast x = Just mempty
+    | Just (x :: EpAnn EpAnnHsCase) <- cast x = Just mempty
+    | Just (x :: EpAnn EpAnnImportDecl) <- cast x = Just mempty
     | Just (x :: EpAnn EpAnnSumPat) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnSig) <- cast x = Just mempty
+    | Just (x :: EpAnn EpAnnUnboundVar) <- cast x = Just mempty
+    | Just (x :: EpAnn GrhsAnn) <- cast x = Just mempty
     | Just (x :: EpAnn HsRuleAnn) <- cast x = Just mempty
-    | Just (x :: EpAnn EpAnnImportDecl) <- cast x = Just mempty
+    | Just (x :: EpAnn NameAnn) <- cast x = Just mempty
+    | Just (x :: EpAnn NoEpAnns) <- cast x = Just mempty
+    | Just (x :: EpAnn [AddEpAnn]) <- cast x = Just mempty
     | Just (x :: EpAnn (AddEpAnn, AddEpAnn)) <- cast x = Just mempty
-    | Just (x :: EpAnn AnnsIf) <- cast x = Just mempty
     | Just (x :: TokenLocation) <- cast y = Just mempty
     | Just (y :: SrcSpan) <- cast y = Just mempty
 
@@ -228,7 +227,7 @@
 -- dot at the root, since otherwise you get two matches because of
 -- 'readRule' (Bug #570).
 unifyExp' :: NameMatch -> Bool -> LHsExpr GhcPs -> LHsExpr GhcPs -> Maybe (Subst (LHsExpr GhcPs))
--- Don't subsitute for type apps, since no one writes rules imagining
+-- Don't substitute for type apps, since no one writes rules imagining
 -- they exist.
 unifyExp' nm root (L _ (HsVar _ (rdrNameStr -> v))) y | isUnifyVar v, not $ isTypeApp y = Just $ Subst [(v, y)]
 unifyExp' nm root (L _ (HsVar _ x)) (L _ (HsVar _ y)) | nm x y = Just mempty
@@ -288,7 +287,7 @@
 unifyType' :: NameMatch -> LHsType GhcPs -> LHsType GhcPs -> Maybe (Subst (LHsExpr GhcPs))
 unifyType' nm (L loc (HsTyVar _ _ x)) y =
   let wc = HsWC noExtField y :: LHsWcType (NoGhcTc GhcPs)
-      unused = strToVar "__unused__" :: LHsExpr GhcPs
-      appType = L loc (HsAppType noSrcSpan unused wc) :: LHsExpr GhcPs
+      unused = strToVar "__unused__"
+      appType = L loc (HsAppType noExtField unused noHsTok wc)
  in Just $ Subst [(rdrNameStr x, appType)]
 unifyType' nm x y = unifyDef' nm x y
diff --git a/src/GHC/Util/View.hs b/src/GHC/Util/View.hs
--- a/src/GHC/Util/View.hs
+++ b/src/GHC/Util/View.hs
@@ -32,8 +32,8 @@
 data LamConst1 = NoLamConst1 | LamConst1 (LocatedA (HsExpr GhcPs))
 
 instance View (LocatedA (HsExpr GhcPs)) LamConst1 where
-  view (fromParen -> (L _ (HsLam _ (MG _ (L _ [L _ (Match _ LambdaExpr [L _ WildPat {}]
-    (GRHSs _ [L _ (GRHS _ [] x)] ((EmptyLocalBinds _))))]) FromSource)))) = LamConst1 x
+  view (fromParen -> (L _ (HsLam _ (MG FromSource (L _ [L _ (Match _ LambdaExpr [L _ WildPat {}]
+    (GRHSs _ [L _ (GRHS _ [] x)] ((EmptyLocalBinds _))))]))))) = LamConst1 x
   view _ = NoLamConst1
 
 instance View (LocatedA (HsExpr GhcPs)) RdrName_ where
@@ -62,4 +62,4 @@
 
 -- A lambda with no guards and no where clauses
 pattern SimpleLambda :: [LocatedA (Pat GhcPs)] -> LocatedA (HsExpr GhcPs) -> LocatedA (HsExpr GhcPs)
-pattern SimpleLambda vs body <- L _ (HsLam _ (MG _ (L _ [L _ (Match _ _ vs (GRHSs _ [L _ (GRHS _ [] body)] ((EmptyLocalBinds _))))]) _))
+pattern SimpleLambda vs body <- L _ (HsLam _ (MG _ (L _ [L _ (Match _ _ vs (GRHSs _ [L _ (GRHS _ [] body)] ((EmptyLocalBinds _))))])))
diff --git a/src/HLint.hs b/src/HLint.hs
--- a/src/HLint.hs
+++ b/src/HLint.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# OPTIONS_GHC -Wno-incomplete-patterns #-}
@@ -17,6 +18,7 @@
 import System.IO.Extra
 import System.Time.Extra
 import Data.Tuple.Extra
+import Data.Bifunctor (bimap)
 import Prelude
 
 import CmdLine
@@ -36,6 +38,7 @@
 import CC
 import EmbedData
 
+import SARIF qualified
 
 -- | This function takes a list of command line arguments, and returns the given hints.
 --   To see a list of arguments type @hlint --help@ at the console.
@@ -167,12 +170,13 @@
 runHints args settings cmd@CmdMain{..} =
     withNumCapabilities cmdThreads $ do
         let outStrLn = whenNormal . putStrLn
-        ideas <- getIdeas cmd settings
-        ideas <- pure $ if cmdShowAll then ideas else  filter (\i -> ideaSeverity i /= Ignore) ideas
+        ideas <- filterIdeas <$> getIdeas cmd settings
         if cmdJson then
             putStrLn $ showIdeasJson ideas
          else if cmdCC then
             mapM_ (printIssue . fromIdea) ideas
+         else if cmdSARIF then
+            SARIF.printIdeas ideas
          else if cmdSerialise then do
             hSetBuffering stdout NoBuffering
             print $ map (show &&& ideaRefactoring) ideas
@@ -184,6 +188,12 @@
             mapM_ (outStrLn . showItem) ideas
             handleReporting ideas cmd
         pure ideas
+  where
+    filteredSeverities
+        | cmdShowAll = []
+        | cmdIgnoreSuggestions = [Ignore, Suggestion]
+        | otherwise = [Ignore]
+    filterIdeas = filter (\i -> ideaSeverity i `notElem` filteredSeverities)
 
 getIdeas :: Cmd -> [Setting] -> IO [Idea]
 getIdeas cmd@CmdMain{..} settings = do
@@ -219,8 +229,14 @@
         outStrLn $ "Writing report to " ++ x ++ " ..."
         writeReport cmdDataDir x showideas
     unless cmdNoSummary $ do
-        let n = length showideas
-        outStrLn $ if n == 0 then "No hints" else show n ++ " hint" ++ ['s' | n/=1]
+        let (nbErrors, nbHints) = bimap length length $ partition (\idea -> ideaSeverity idea == Error) showideas
+        when (nbErrors > 0) (outStrLn $ formatOutput nbErrors "error")
+        unless (nbErrors > 0 && nbHints == 0) (outStrLn $ formatOutput nbHints "hint")
+
+    where
+        formatOutput :: Int -> String -> String
+        formatOutput number name =
+            if number == 0 then "No " ++ name ++ "s" else show number ++ " " ++ name ++ ['s' | number/=1]
 
 evaluateList :: [a] -> IO [a]
 evaluateList xs = do
diff --git a/src/Hint/Bracket.hs b/src/Hint/Bracket.hs
--- a/src/Hint/Bracket.hs
+++ b/src/Hint/Bracket.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE ViewPatterns, ScopedTypeVariables #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE TypeFamilies #-}
@@ -45,6 +46,13 @@
 issue1179 = do(this is a test) -- do this is a test
 issue1212 = $(Git.hash)
 
+-- no record dot syntax
+referenceDesignator = ReferenceDesignator (p.placementReferenceDesignator)
+
+-- record dot syntax
+{-# LANGUAGE OverloadedRecordDot #-} \
+referenceDesignator = ReferenceDesignator (p.placementReferenceDesignator) -- p.placementReferenceDesignator @NoRefactor: refactor requires GHC >= 9.2.1
+
 -- type bracket reduction
 foo :: (Int -> Int) -> Int
 foo :: (Maybe Int) -> a -- @Suggestion Maybe Int -> a
@@ -104,6 +112,17 @@
 
 -- template haskell is harder
 issue1292 = [e| handleForeignCatch $ \ $(varP pylonExPtrVarName) -> $(quoteExp C.block modifiedStr) |]
+
+-- no warnings for single-argument constraint contexts
+foo :: (A) => ()
+bar :: (A a) => ()
+foo' :: ((A) => ()) -> ()
+bar' :: ((A a) => ()) -> ()
+data Dict c where Dict :: (c) => Dict c
+data Dict' c a where Dict' :: (c a) => Dict' c a
+
+-- issue1501: Redundant bracket hint resulted in a parse error
+x = f $ \(Proxy @a) -> True
 </TEST>
 -}
 
@@ -127,10 +146,17 @@
 bracketHint :: DeclHint
 bracketHint _ _ x =
   concatMap (\x -> bracket prettyExpr isPartialAtom True x ++ dollar x) (childrenBi (descendBi splices $ descendBi annotations x) :: [LHsExpr GhcPs]) ++
-  concatMap (bracket unsafePrettyPrint (\_ _ -> False) False) (childrenBi x :: [LHsType GhcPs]) ++
+  concatMap (bracket unsafePrettyPrint (\_ _ -> False) False) (childrenBi (preprocess x) :: [LHsType GhcPs]) ++
   concatMap (bracket unsafePrettyPrint (\_ _ -> False) False) (childrenBi x :: [LPat GhcPs]) ++
   concatMap fieldDecl (childrenBi x)
    where
+     preprocess = transformBi removeSingleAtomConstrCtxs
+       where
+         removeSingleAtomConstrCtxs :: LHsContext GhcPs -> LHsContext GhcPs
+         removeSingleAtomConstrCtxs = fmap $ \case
+           [ty] | isAtom ty -> []
+           tys -> tys
+
      -- Brackets the roots of annotations are fine, so we strip them.
      annotations :: AnnDecl GhcPs -> AnnDecl GhcPs
      annotations= descendBi $ \x -> case (x :: LHsExpr GhcPs) of
@@ -145,7 +171,7 @@
      splices x = x
 
 -- If we find ourselves in the context of a section and we want to
--- issue a warning that a child therein has unneccessary brackets,
+-- issue a warning that a child therein has unnecessary brackets,
 -- we'd rather report 'Found : (`Foo` (Bar Baz))' rather than 'Found :
 -- `Foo` (Bar Baz)'. If left to 'unsafePrettyPrint' we'd get the
 -- latter (in contrast to the HSE pretty printer). This patches things
@@ -162,12 +188,15 @@
   where
     go e = maybe e go (remParen e)
 
+-- note(sf, 2022-06-02): i've completely bluffed my way through this.
+-- see
+-- https://gitlab.haskell.org/ghc/ghc/-/commit/7975202ba9010c581918413808ee06fbab9ac85f
+-- for where splice expressions were refactored.
 isPartialAtom :: Maybe (LHsExpr GhcPs) -> LHsExpr GhcPs -> Bool
 -- Might be '$x', which was really '$ x', but TH enabled misparsed it.
-isPartialAtom _ (L _ (HsSpliceE _ (HsTypedSplice _ DollarSplice _ _) )) = True
-isPartialAtom _ (L _ (HsSpliceE _ (HsUntypedSplice _ DollarSplice _ _) )) = True
+isPartialAtom _ (L _ (HsUntypedSplice _ HsUntypedSpliceExpr{})) = True
 -- Might be '$(x)' where the brackets are required in GHC 8.10 and below
-isPartialAtom (Just (L _ HsSpliceE{})) _ = True
+isPartialAtom (Just (L _ HsUntypedSplice{})) _ = True
 isPartialAtom _ x = isRecConstr x || isRecUpdate x
 
 bracket :: forall a . (Data a, Outputable a, Brackets (LocatedA a)) => (LocatedA a -> String) -> (Maybe (LocatedA a) -> LocatedA a -> Bool) -> Bool -> LocatedA a -> [Idea]
diff --git a/src/Hint/Comment.hs b/src/Hint/Comment.hs
--- a/src/Hint/Comment.hs
+++ b/src/Hint/Comment.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 
 {-
 <TEST>
@@ -21,7 +22,7 @@
 import GHC.Types.SrcLoc
 import GHC.Parser.Annotation
 import GHC.Util
-import qualified GHC.Data.Strict
+import GHC.Data.Strict qualified
 
 directives :: [String]
 directives = words $
diff --git a/src/Hint/Duplicate.hs b/src/Hint/Duplicate.hs
--- a/src/Hint/Duplicate.hs
+++ b/src/Hint/Duplicate.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE PatternGuards, ScopedTypeVariables #-}
 {-# LANGUAGE FlexibleContexts #-}
 
@@ -30,8 +31,8 @@
 import Data.Maybe
 import Data.Tuple.Extra
 import Data.List hiding (find)
-import qualified Data.List.NonEmpty as NE
-import qualified Data.Map as Map
+import Data.List.NonEmpty qualified as NE
+import Data.Map qualified as Map
 
 import GHC.Types.SrcLoc
 import GHC.Hs
diff --git a/src/Hint/Export.hs b/src/Hint/Export.hs
--- a/src/Hint/Export.hs
+++ b/src/Hint/Export.hs
@@ -16,7 +16,6 @@
 import Hint.Type(ModuHint, ModuleEx(..),ideaNote,ignore,Note(..))
 
 import GHC.Hs
-import GHC.Unit.Module
 import GHC.Types.SrcLoc
 import GHC.Types.Name.Occurrence
 import GHC.Types.Name.Reader
@@ -33,11 +32,11 @@
   , exports' <- [x | x <- xs, not (matchesModName modName x)]
   , modName `elem` names =
       let dots = mkRdrUnqual (mkVarOcc " ... ")
-          r = o{ hsmodExports = Just (noLocA (noLocA (IEVar noExtField (noLocA (IEName (noLocA dots)))) : exports') )}
+          r = o{ hsmodExports = Just (noLocA (noLocA (IEVar noExtField (noLocA (IEName noExtField (noLocA dots)))) : exports') )}
       in
         [ignore "Use explicit module export list" (L s o) (noLoc r) []]
       where
-          o = m{hsmodImports=[], hsmodDecls=[], hsmodDeprecMessage=Nothing, hsmodHaddockModHeader=Nothing }
+          o = m{hsmodImports=[], hsmodDecls=[] }
           isMod (L _ (IEModuleContents _ _)) = True
           isMod _ = False
 
diff --git a/src/Hint/Extensions.hs b/src/Hint/Extensions.hs
--- a/src/Hint/Extensions.hs
+++ b/src/Hint/Extensions.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE LambdaCase, NamedFieldPuns, ScopedTypeVariables #-}
 
 {-
@@ -98,7 +99,7 @@
 {-# LANGUAGE DeriveGeneric, GeneralizedNewtypeDeriving #-} \
 newtype Micro = Micro Int deriving Generic -- {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DeriveGeneric, TypeFamilies #-} \
-data family Bar a; data instance Bar Foo = Foo deriving (Generic)
+data family Bar a; data instance Bar Foo = Foo deriving Generic
 {-# LANGUAGE GeneralizedNewtypeDeriving #-} \
 instance Class Int where {newtype MyIO a = MyIO a deriving NewClass}
 {-# LANGUAGE UnboxedTuples #-} \
@@ -248,13 +249,18 @@
 foo = [|| x ||]
 {-# LANGUAGE TemplateHaskell #-} \
 foo = $bar
+{-# LANGUAGE TypeData # -} \
+type data Nat = Zero | Succ Nat  -- @NoRefactor: refactor requires GHC >= 9.6.1
+{-# LANGUAGE TypeData #-} \
+data T = MkT -- @NoRefactor: refactor requires GHC >= 9.6.1
 </TEST>
 -}
 
 
+
 module Hint.Extensions(extensionsHint) where
 
-import Hint.Type(ModuHint,rawIdea,Severity(Warning),Note(..),toSSAnc,ghcModule,modComments)
+import Hint.Type(ModuHint,rawIdea,Severity(Warning),Note(..),toSSAnc,ghcModule,modComments,firstDeclComments)
 import Extension
 
 import Data.Generics.Uniplate.DataOnly
@@ -263,8 +269,8 @@
 import Data.List.Extra
 import Data.Data
 import Refact.Types
-import qualified Data.Set as Set
-import qualified Data.Map as Map
+import Data.Set qualified as Set
+import Data.Map qualified as Map
 
 import GHC.Types.SrcLoc
 import GHC.Types.SourceText
@@ -272,7 +278,7 @@
 import GHC.Types.Basic
 import GHC.Types.Name.Reader
 import GHC.Types.ForeignCall
-import qualified GHC.Data.Strict
+import GHC.Data.Strict qualified
 import GHC.Types.PkgQual
 
 import GHC.Util
@@ -299,7 +305,13 @@
             [ Note $ "Extension " ++ s ++ " is " ++ reason x
             | (s, Just x) <- explainedRemovals])
         [ModifyComment (toSSAnc (mkLanguagePragmas sl exts)) newPragma]
-    | (L sl _,  exts) <- languagePragmas $ pragmas (modComments x)
+    | (L sl _,  exts) <-
+      -- Comments appearing without an empty line before the first
+      -- declaration in a module are now associated with the
+      -- declaration not the module so to be safe, look also at
+      -- `firstDeclComments x`
+      -- (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
+      languagePragmas $ pragmas (modComments x) ++ pragmas (firstDeclComments x)
     , let before = [(x, readExtension x) | x <- exts]
     , let after = filter (maybe True (`Set.member` keep) . snd) before
     , before /= after
@@ -319,8 +331,16 @@
 
     -- All the extensions defined to be used.
     extensions :: Set.Set Extension
-    extensions = Set.fromList $ mapMaybe readExtension $
-        concatMap snd $ languagePragmas (pragmas (modComments x))
+    extensions = Set.fromList $
+      concatMap
+      (mapMaybe readExtension . snd)
+      (languagePragmas
+        (pragmas (modComments x) ++ pragmas (firstDeclComments x)))
+      -- Comments appearing without an empty line before the first
+      -- declaration in a module are now associated with the
+      -- declaration not the module so to be safe, look also at
+      -- `firstDeclComments x`
+      -- (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
 
     -- Those extensions we detect to be useful.
     useful :: Set.Set Extension
@@ -370,7 +390,7 @@
 deriveStock :: [String]
 deriveStock = deriveHaskell ++ deriveGenerics ++ deriveCategory
 
-usedExt :: Extension -> Located HsModule -> Bool
+usedExt :: Extension -> Located (HsModule GhcPs) -> Bool
 usedExt NumDecimals = hasS isWholeFrac
   -- Only whole number fractions are permitted by NumDecimals
   -- extension.  Anything not-whole raises an error.
@@ -378,23 +398,30 @@
 usedExt DeriveAnyClass = not . null . derivesAnyclass . derives
 usedExt x = used x
 
-used :: Extension -> Located HsModule -> Bool
+used :: Extension -> Located (HsModule GhcPs) -> Bool
 
 used RecursiveDo = hasS isMDo ||^ hasS isRecStmt
 used ParallelListComp = hasS isParComp
 used FunctionalDependencies = hasT (un :: FunDep GhcPs)
 used ImplicitParams = hasT (un :: HsIPName)
+
 used TypeApplications = hasS isTypeApp ||^ hasS isKindTyApp
+
 used EmptyDataDecls = hasS f
   where
     f :: HsDataDefn GhcPs -> Bool
-    f (HsDataDefn _ _ _ _ _ [] _) = True
+    f (HsDataDefn _ _ _ _ (DataTypeCons _ []) _) = True
     f _ = False
+used TypeData  = hasS f
+  where
+    f :: HsDataDefn GhcPs -> Bool
+    f (HsDataDefn _ _ _ _ (DataTypeCons True _) _) = True
+    f _ = False
 used EmptyCase = hasS f
   where
     f :: HsExpr GhcPs -> Bool
-    f (HsCase _ _ (MG _ (L _ []) _)) = True
-    f (HsLamCase _ _ (MG _ (L _ []) _)) = True
+    f (HsCase _ _ (MG _ (L _ []))) = True
+    f (HsLamCase _ _ (MG _ (L _ []))) = True
     f _ = False
 used KindSignatures = hasT (un :: HsKind GhcPs)
 used BangPatterns = hasS isPBangPat ||^ hasS isStrictMatch
@@ -497,7 +524,7 @@
 
 used _= const True
 
-hasDerive :: [String] -> Located HsModule -> Bool
+hasDerive :: [String] -> Located (HsModule GhcPs) -> Bool
 hasDerive want = any (`elem` want) . derivesStock' . derives
 
 -- Derivations can be implemented using any one of 3 strategies, so for each derivation
@@ -526,14 +553,14 @@
     ,derivesNewtype' = if maybe True isNewType nt then filter (`notElem` noDeriveNewtype) xs else []}
     where (stock, other) = partition (`elem` deriveStock) xs
 
-derives :: Located HsModule -> Derives
+derives :: Located (HsModule GhcPs) -> Derives
 derives (L _ m) =  mconcat $ map decl (childrenBi m) ++ map idecl (childrenBi m)
   where
     idecl :: DataFamInstDecl GhcPs -> Derives
-    idecl (DataFamInstDecl FamEqn {feqn_rhs=HsDataDefn {dd_ND=dn, dd_derivs=ds}}) = g dn ds
+    idecl (DataFamInstDecl FamEqn {feqn_rhs=HsDataDefn {dd_cons=data_defn_cons, dd_derivs=ds}}) = g (dataDefnConsNewOrData data_defn_cons) ds
 
     decl :: LHsDecl GhcPs -> Derives
-    decl (L _ (TyClD _ (DataDecl _ _ _ _ HsDataDefn {dd_ND=dn, dd_derivs=ds}))) = g dn ds -- Data declaration.
+    decl (L _ (TyClD _ (DataDecl _ _ _ _ HsDataDefn {dd_cons=data_defn_cons, dd_derivs=ds}))) = g (dataDefnConsNewOrData data_defn_cons) ds -- Data declaration.
     decl (L _ (DerivD _ (DerivDecl _ (HsWC _ sig) strategy _))) = addDerives Nothing (fmap unLoc strategy) [derivedToStr sig] -- A deriving declaration.
     decl _ = mempty
 
diff --git a/src/Hint/Import.hs b/src/Hint/Import.hs
--- a/src/Hint/Import.hs
+++ b/src/Hint/Import.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE LambdaCase, PatternGuards, RecordWildCards #-}
 {-
     Reduce the number of import declarations.
@@ -39,7 +40,7 @@
 
 import Hint.Type(ModuHint,ModuleEx(..),Idea(..),Severity(..),suggest,toSSA,rawIdea)
 import Refact.Types hiding (ModuleName)
-import qualified Refact.Types as R
+import Refact.Types qualified as R
 import Data.Tuple.Extra
 import Data.List.Extra
 import Data.Generics.Uniplate.DataOnly
@@ -51,7 +52,6 @@
 import GHC.Types.SourceText
 import GHC.Hs
 import GHC.Types.SrcLoc
-import GHC.Unit.Types -- for 'NotBoot'
 import GHC.Types.PkgQual
 
 import Language.Haskell.GhclibParserEx.GHC.Utils.Outputable
@@ -107,15 +107,15 @@
     -- Both (un/)qualified, common 'as', different names : Merge the
     -- second into the first and delete it.
   | qual, as
-  , Just (False, xs) <- ideclHiding x'
-  , Just (False, ys) <- ideclHiding y' =
-      let newImp = L loc x'{ideclHiding = Just (False, noLocA (unLoc xs ++ unLoc ys))}
+  , Just (False, xs) <- first (== EverythingBut) <$> ideclImportList x'
+  , Just (False, ys) <- first (== EverythingBut) <$> ideclImportList y' =
+      let newImp = L loc x'{ideclImportList = Just (Exactly, noLocA (unLoc xs ++ unLoc ys))}
       in Just (newImp, [Replace Import (toSSA x) [] (unsafePrettyPrint (unLoc newImp))
                        , Delete Import (toSSA y)])
   -- Both (un/qualified), common 'as', one has names the other doesn't
   -- : Delete the one with names.
-  | qual, as, isNothing (ideclHiding x') || isNothing (ideclHiding y') =
-       let (newImp, toDelete) = if isNothing (ideclHiding x') then (x, y) else (y, x)
+  | qual, as, isNothing (ideclImportList x') || isNothing (ideclImportList y') =
+       let (newImp, toDelete) = if isNothing (ideclImportList x') then (x, y) else (y, x)
        in Just (newImp, [Delete Import (toSSA toDelete)])
   -- Both unqualified, same names, one (and only one) has an 'as'
   -- clause : Delete the one without an 'as'.
@@ -133,8 +133,8 @@
         qual = ideclQualified x' == ideclQualified y'
         as = ideclAs x' `eqMaybe` ideclAs y'
         ass = mapMaybe ideclAs [x', y']
-        specs = transformBi (const noSrcSpan) (ideclHiding x') ==
-                    transformBi (const noSrcSpan) (ideclHiding y')
+        specs = transformBi (const noSrcSpan) (ideclImportList x') ==
+                    transformBi (const noSrcSpan) (ideclImportList y')
 
 stripRedundantAlias :: LImportDecl GhcPs -> [Idea]
 stripRedundantAlias x@(L _ i@ImportDecl {..})
diff --git a/src/Hint/Lambda.hs b/src/Hint/Lambda.hs
--- a/src/Hint/Lambda.hs
+++ b/src/Hint/Lambda.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE LambdaCase, PatternGuards, TupleSections, ViewPatterns #-}
 
 {-
@@ -110,7 +111,7 @@
 import Util
 import Data.List.Extra
 import Data.Set (Set)
-import qualified Data.Set as Set
+import Data.Set qualified as Set
 import Refact.Types hiding (Match)
 import Data.Generics.Uniplate.DataOnly (universe, universeBi, transformBi)
 
@@ -169,7 +170,7 @@
     where
           reform :: [LPat GhcPs] -> LHsExpr GhcPs -> Located (HsDecl GhcPs)
           reform ps b = L (combineSrcSpans (locA loc1) (locA loc2)) $ ValD noExtField $
-             origBind {fun_matches = MG noExtField (noLocA [noLocA $ Match EpAnnNotUsed ctxt ps $ GRHSs emptyComments [noLocA $ GRHS EpAnnNotUsed [] b] $ EmptyLocalBinds noExtField]) Generated}
+             origBind {fun_matches = MG Generated (noLocA [noLocA $ Match EpAnnNotUsed ctxt ps $ GRHSs emptyComments [noLocA $ GRHS EpAnnNotUsed [] b] $ EmptyLocalBinds noExtField])}
 
           mkSubtsAndTpl newPats newBody = (sub, tpl)
             where
@@ -265,7 +266,7 @@
                  -- we need to
                  --     * add brackets to the match, because matches in lambdas require them
                  --     * mark match as being in a lambda context so that it's printed properly
-                 oldMG@(MG _ (L _ [L _ oldmatch]) _)
+                 oldMG@(MG _ (L _ [L _ oldmatch]))
                    | all (\(L _ (GRHS _ stmts _)) -> null stmts) (grhssGRHSs (m_grhss oldmatch)) ->
                      let patLocs = fmap (locA . getLoc) (m_pats oldmatch)
                          bodyLocs = concatMap (\case L _ (GRHS _ _ body) -> [locA (getLoc body)])
@@ -293,7 +294,7 @@
                          ]
 
                  -- otherwise we should use @LambdaCase@
-                 MG _ (L _ _) _ ->
+                 MG _ (L _ _) ->
                      [(suggestN "Use lambda-case" (reLoc o) $ noLoc $ HsLamCase EpAnnNotUsed LamCase matchGroup)
                          {ideaNote=[RequiresExtension "LambdaCase"]}]
         _ -> []
diff --git a/src/Hint/List.hs b/src/Hint/List.hs
--- a/src/Hint/List.hs
+++ b/src/Hint/List.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE ViewPatterns, PatternGuards, FlexibleContexts #-}
 {-
     Find and match:
@@ -47,14 +48,13 @@
 import Data.Maybe
 import Prelude
 
-import Hint.Type(DeclHint,Idea,suggest,ignore,substVars,toRefactSrcSpan,toSSA,modComments)
+import Hint.Type(DeclHint,Idea,suggest,ignore,substVars,toRefactSrcSpan,toSSA,modComments,firstDeclComments)
 
 import Refact.Types hiding (SrcSpan)
-import qualified Refact.Types as R
+import Refact.Types qualified as R
 
 import GHC.Hs
 import GHC.Types.SrcLoc
-import GHC.Types.Basic hiding (Pattern)
 import GHC.Types.SourceText
 import GHC.Types.Name.Reader
 import GHC.Data.FastString
@@ -72,7 +72,11 @@
 listHint :: DeclHint
 listHint _ modu = listDecl overloadedListsOn
   where
-    exts = concatMap snd (languagePragmas (pragmas (modComments modu)))
+    -- Comments appearing without a line-break before the first
+    -- declaration in a module are now associated with the declaration
+    -- not the module so to be safe, look also at `firstDeclComments
+    -- modu` (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
+    exts = concatMap snd (languagePragmas (pragmas (modComments modu) ++ pragmas (firstDeclComments modu)))
     overloadedListsOn = "OverloadedLists" `elem` exts
 
 listDecl :: Bool -> LHsDecl GhcPs -> [Idea]
@@ -271,7 +275,7 @@
   InstD _ ClsInstD{
     cid_inst=
         ClsInstDecl{cid_binds=x, cid_tyfam_insts=y, cid_datafam_insts=z}} ->
-    f x ++ f y ++ f z -- Pretty much everthing but the instance type.
+    f x ++ f y ++ f z -- Pretty much everything but the instance type.
   _ -> f x
   where
     f x = concatMap g $ childrenBi x
diff --git a/src/Hint/ListRec.hs b/src/Hint/ListRec.hs
--- a/src/Hint/ListRec.hs
+++ b/src/Hint/ListRec.hs
@@ -135,7 +135,7 @@
 asDo (view ->
        App2 bind lhs
          (L _ (HsLam _ MG {
-              mg_origin=FromSource
+              mg_ext=FromSource
             , mg_alts=L _ [
                  L _ Match {  m_ctxt=LambdaExpr
                             , m_pats=[v@(L _ VarPat{})]
@@ -157,7 +157,7 @@
 findCase x = do
   -- Match a function binding with two alternatives.
   (L _ (ValD _ FunBind {fun_matches=
-              MG{mg_origin=FromSource, mg_alts=
+              MG{mg_ext=FromSource, mg_alts=
                      (L _
                             [ x1@(L _ Match{..}) -- Match fields.
                             , x2]), ..} -- Match group fields.
@@ -176,7 +176,7 @@
       gRHS e = noLocA $ GRHS EpAnnNotUsed [] e :: LGRHS GhcPs (LHsExpr GhcPs) -- Guarded rhs.
       gRHSSs e = GRHSs emptyComments [gRHS e] emptyLocalBinds -- Guarded rhs set.
       match e = Match{m_ext=EpAnnNotUsed,m_pats=ps12, m_grhss=gRHSSs e, ..} -- Match.
-      matchGroup e = MG{mg_alts=noLocA [noLocA $ match e], mg_origin=Generated, ..} -- Match group.
+      matchGroup e = MG{mg_alts=noLocA [noLocA $ match e], mg_ext=Generated, ..} -- Match group.
       funBind e = FunBind {fun_matches=matchGroup e, ..} :: HsBindLR GhcPs GhcPs -- Fun bind.
 
   pure (ListCase ps b1 (x, xs, b2), noLocA . ValD noExtField . funBind)
diff --git a/src/Hint/Match.hs b/src/Hint/Match.hs
--- a/src/Hint/Match.hs
+++ b/src/Hint/Match.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE RecordWildCards, NamedFieldPuns, TupleSections #-}
 {-# LANGUAGE PatternGuards, ViewPatterns, FlexibleContexts #-}
 
@@ -43,8 +44,8 @@
 
 import Util
 import Timing
-import qualified Data.Set as Set
-import qualified Refact.Types as R
+import Data.Set qualified as Set
+import Refact.Types qualified as R
 
 import Control.Monad
 import Data.Tuple.Extra
@@ -200,7 +201,7 @@
       isType "Compare" x = True -- Just a hint for proof stuff
       isType "Atom" x = isAtom x
       isType "WHNF" x = isWHNF x
-      isType "Wildcard" x = any isFieldPun (universeBi x) || any hasFieldsDotDot (universeBi x)
+      isType "Wildcard" x = any hasFieldsDotDot (universeBi x)
       isType "Nat" (asInt -> Just x) | x >= 0 = True
       isType "Pos" (asInt -> Just x) | x >  0 = True
       isType "Neg" (asInt -> Just x) | x <  0 = True
diff --git a/src/Hint/Monad.hs b/src/Hint/Monad.hs
--- a/src/Hint/Monad.hs
+++ b/src/Hint/Monad.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE PatternGuards #-}
@@ -77,7 +78,7 @@
 import GHC.Types.Name.Reader
 import GHC.Types.Name.Occurrence
 import GHC.Data.Bag
-import qualified GHC.Data.Strict
+import GHC.Data.Strict qualified
 
 import Language.Haskell.GhclibParserEx.GHC.Hs.Pat
 import Language.Haskell.GhclibParserEx.GHC.Hs.Expr
@@ -90,7 +91,7 @@
 import Data.Maybe
 import Data.List.Extra
 import Refact.Types hiding (Match)
-import qualified Refact.Types as R
+import Refact.Types qualified as R
 
 
 badFuncs :: [String]
@@ -173,9 +174,9 @@
 doAsBrackets Nothing x = False
 
 
--- Sometimes people write do, to avoid identation, see
+-- Sometimes people write do, to avoid indentation, see
 -- https://github.com/ndmitchell/hlint/issues/978
--- Return True if they are using do as avoiding identation
+-- Return True if they are using do as avoiding indentation
 doAsAvoidingIndentation :: Maybe (LHsExpr GhcPs) -> LHsExpr GhcPs -> Bool
 doAsAvoidingIndentation (Just (L _ (HsDo _ _ (L anna _)))) (L _ (HsDo _ _ (L annb _)))
   | SrcSpanAnn _ (RealSrcSpan a _) <- anna
@@ -189,7 +190,7 @@
 modifyAppHead f = go id
   where
     go :: (LHsExpr GhcPs -> LHsExpr GhcPs) -> LHsExpr GhcPs -> (LHsExpr GhcPs, Maybe a)
-    go wrap (L l (HsPar _ p x q )) = go (wrap . L l . \x -> HsPar EpAnnNotUsed p x q) x
+    go wrap (L l (HsPar _ p x q)) = go (wrap . L l . \y -> HsPar EpAnnNotUsed p y q) x
     go wrap (L l (HsApp _ x y)) = go (\x -> wrap $ L l (HsApp EpAnnNotUsed x y)) x
     go wrap (L l (OpApp _ x op y)) | isDol op = go (\x -> wrap $ L l (OpApp EpAnnNotUsed x op y)) x
     go wrap (L l (HsVar _ x)) = (wrap (L l (HsVar NoExtField x')), Just a)
@@ -297,7 +298,7 @@
             grhs = noLocA (GRHS EpAnnNotUsed [] rhs)
             grhss = GRHSs emptyComments [grhs] (EmptyLocalBinds noExtField)
             match = noLocA $ Match EpAnnNotUsed (FunRhs p Prefix NoSrcStrict) [] grhss
-            fb = noLocA $ FunBind noExtField p (MG noExtField (noLocA [match]) Generated) []
+            fb = noLocA $ FunBind noExtField p (MG Generated (noLocA [match]))
             binds = unitBag fb
             valBinds = ValBinds NoAnnSortKey binds []
             localBinds = HsValBinds EpAnnNotUsed valBinds
diff --git a/src/Hint/Naming.hs b/src/Hint/Naming.hs
--- a/src/Hint/Naming.hs
+++ b/src/Hint/Naming.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-
@@ -44,10 +45,11 @@
 import Hint.Type (Idea,DeclHint,suggest,ghcModule)
 import Data.Generics.Uniplate.DataOnly
 import Data.List.Extra (nubOrd, isPrefixOf)
+import Data.List.NonEmpty (toList)
 import Data.Data
 import Data.Char
 import Data.Maybe
-import qualified Data.Set as Set
+import Data.Set qualified as Set
 
 import GHC.Types.Basic
 import GHC.Types.SourceText
@@ -85,9 +87,9 @@
         replacedDecl = replaceNames suggestedNames originalDecl
 
 shorten :: LHsDecl GhcPs -> LHsDecl GhcPs
-shorten (L locDecl (ValD ttg0 bind@(FunBind _ _ matchGroup@(MG _ (L locMatches matches) FromSource) _))) =
+shorten (L locDecl (ValD ttg0 bind@(FunBind _ _ matchGroup@(MG FromSource (L locMatches matches))))) =
     L locDecl (ValD ttg0 bind {fun_matches = matchGroup {mg_alts = L locMatches $ map shortenMatch matches}})
-shorten (L locDecl (ValD ttg0 bind@(PatBind _ _ grhss@(GRHSs _ rhss _) _))) =
+shorten (L locDecl (ValD ttg0 bind@(PatBind _ _ grhss@(GRHSs _ rhss _)))) =
     L locDecl (ValD ttg0 bind {pat_rhs = grhss {grhssGRHSs = map shortenLGRHS rhss}})
 shorten x = x
 
@@ -106,14 +108,17 @@
 getNames decl = maybeToList (declName decl) ++ getConstructorNames (unLoc decl)
 
 getConstructorNames :: HsDecl GhcPs -> [String]
-getConstructorNames (TyClD _ (DataDecl _ _ _ _ (HsDataDefn _ _ _ _ _ cons _))) =
-    concatMap (map unsafePrettyPrint . getConNames' . unLoc) cons
-    where
-      getConNames' ConDeclH98  {con_name  = name}  = [name]
-      getConNames' ConDeclGADT {con_names = names} = names
-      getConNames' XConDecl{} = []
+getConstructorNames tycld = case tycld of
+    (TyClD _ (DataDecl _ _ _ _ (HsDataDefn _ _ _ _ (NewTypeCon con) _))) -> conNames [con]
+    (TyClD _ (DataDecl _ _ _ _ (HsDataDefn _ _ _ _ (DataTypeCons _ cons) _))) -> conNames cons
+    _ -> []
+  where
+    conNames :: [LConDecl GhcPs] -> [String]
+    conNames =  concatMap (map unsafePrettyPrint . conNamesInDecl . unLoc)
 
-getConstructorNames _ = []
+    conNamesInDecl :: ConDecl GhcPs -> [LIdP GhcPs]
+    conNamesInDecl ConDeclH98  {con_name  = name}  = [name]
+    conNamesInDecl ConDeclGADT {con_names = names} = Data.List.NonEmpty.toList names
 
 isSym :: String -> Bool
 isSym (x:_) = not $ isAlpha x || x `elem` "_'"
diff --git a/src/Hint/NewType.hs b/src/Hint/NewType.hs
--- a/src/Hint/NewType.hs
+++ b/src/Hint/NewType.hs
@@ -72,12 +72,11 @@
 shouldSuggestStrategies dataDef = not (isData dataDef) && not (hasAllStrategies dataDef)
 
 hasAllStrategies :: HsDataDefn GhcPs -> Bool
-hasAllStrategies (HsDataDefn _ NewType _ _ _ _  xs) = all hasStrategyClause xs
-hasAllStrategies _ = False
+hasAllStrategies (HsDataDefn _ _ _ _ _  xs) = all hasStrategyClause xs
 
 isData :: HsDataDefn GhcPs -> Bool
-isData (HsDataDefn _ NewType _ _ _ _ _) = False
-isData (HsDataDefn _ DataType _ _ _ _ _) = True
+isData (HsDataDefn _ _ _ _ (NewTypeCon _) _) = False
+isData (HsDataDefn _ _ _ _ (DataTypeCons _ _) _) = True
 
 hasStrategyClause :: LHsDerivingClause GhcPs -> Bool
 hasStrategyClause (L _ (HsDerivingClause _ (Just _) _)) = True
@@ -98,31 +97,39 @@
 singleSimpleField :: LHsDecl GhcPs -> Maybe WarnNewtype
 singleSimpleField (L loc (TyClD ext decl@(DataDecl _ _ _ _ dataDef)))
     | Just inType <- simpleHsDataDefn dataDef =
-        Just WarnNewtype
+        case dropBangs dataDef of
+          DataTypeCons False [con] ->
+            Just WarnNewtype
               { newDecl = L loc $ TyClD ext decl {tcdDataDefn = dataDef
-                  { dd_ND = NewType
-                  , dd_cons = dropBangs dataDef
-                  }}
+                  { dd_cons = NewTypeCon con }}
               , insideType = inType
               }
+          DataTypeCons True [_] -> Nothing -- Extension "TypeData": `type data T x = ...`
+          _ -> Nothing
 singleSimpleField (L loc (InstD ext (DataFamInstD instExt (DataFamInstDecl famEqn@(FamEqn _ _ _ _ _ dataDef)))))
     | Just inType <- simpleHsDataDefn dataDef =
-        Just WarnNewtype
-          { newDecl = L loc $ InstD ext $ DataFamInstD instExt $ DataFamInstDecl $ famEqn {feqn_rhs = dataDef
-                  { dd_ND = NewType
-                  , dd_cons = dropBangs dataDef
-                  }}
+        case dropBangs dataDef of
+          DataTypeCons False [con] ->
+            Just WarnNewtype
+              { newDecl = L loc $ InstD ext $ DataFamInstD instExt $ DataFamInstDecl $ famEqn {feqn_rhs = dataDef
+                      { dd_cons = NewTypeCon con }}
               , insideType = inType
               }
+          DataTypeCons True [_] -> Nothing --  -- Extension "TypeData": `type data T x = ...`
+          _ -> Nothing
 singleSimpleField _ = Nothing
 
-dropBangs :: HsDataDefn GhcPs -> [LConDecl GhcPs]
-dropBangs = map (fmap dropConsBang) . dd_cons
+dropBangs :: HsDataDefn GhcPs -> DataDefnCons (LConDecl GhcPs)
+dropBangs def =
+  case dd_cons def of
+    NewTypeCon a -> NewTypeCon (dropConsBang <$> a)
+    DataTypeCons isTypeData as -> DataTypeCons isTypeData (map (dropConsBang <$>) as)
 
--- | Checks whether its argument is a \"simple\" data definition (see 'singleSimpleField')
--- returning the type inside its constructor if it is.
+-- | Checks whether its argument is a \"simple\" data definition (see
+-- 'singleSimpleField') returning the single thing under its
+-- constructor if it is.
 simpleHsDataDefn :: HsDataDefn GhcPs -> Maybe (HsType GhcPs)
-simpleHsDataDefn (HsDataDefn _ DataType _ _ _ [L _ constructor] _) = simpleCons constructor
+simpleHsDataDefn (HsDataDefn _ _ _ _ (DataTypeCons _ [L _ constructor]) _) = simpleCons constructor
 simpleHsDataDefn _ = Nothing
 
 -- | Checks whether its argument is a \"simple\" constructor (see criteria in 'singleSimpleField')
diff --git a/src/Hint/NumLiteral.hs b/src/Hint/NumLiteral.hs
--- a/src/Hint/NumLiteral.hs
+++ b/src/Hint/NumLiteral.hs
@@ -4,6 +4,8 @@
 <TEST>
 123456
 {-# LANGUAGE NumericUnderscores #-} \
+1234
+{-# LANGUAGE NumericUnderscores #-} \
 12345 -- @Suggestion 12_345 @NoRefactor
 {-# LANGUAGE NumericUnderscores #-} \
 123456789.0441234e-123456 -- @Suggestion 123_456_789.044_123_4e-123_456 @NoRefactor
@@ -26,15 +28,21 @@
 import GHC.Util.ApiAnnotation (extensions)
 import Data.Char (isDigit, isOctDigit, isHexDigit)
 import Data.List (intercalate)
+import Data.Set (union)
 import Data.Generics.Uniplate.DataOnly (universeBi)
 import Refact.Types
 
-import Hint.Type (DeclHint, toSSA, modComments)
+import Hint.Type (DeclHint, toSSA, modComments, firstDeclComments)
 import Idea (Idea, suggest)
 
 numLiteralHint :: DeclHint
 numLiteralHint _ modu =
-  if NumericUnderscores `elem` extensions (modComments modu) then
+  -- Comments appearing without an empty line before the first
+  -- declaration in a module are now associated with the declaration
+  -- not the module so to be safe, look also at `firstDeclComments
+  -- modu` (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
+  let exts = union (extensions (modComments modu)) (extensions (firstDeclComments modu)) in
+  if NumericUnderscores `elem` exts then
      concatMap suggestUnderscore . universeBi
   else
      const []
@@ -44,12 +52,14 @@
   [ suggest "Use underscore" (reLoc x) (reLoc y) [r] | '_' `notElem` srcTxt, srcTxt /= underscoredSrcTxt ]
   where
     underscoredSrcTxt = addUnderscore srcTxt
+    y :: LocatedAn an (HsExpr GhcPs)
     y = noLocA $ HsOverLit EpAnnNotUsed $ ol{ol_val = HsIntegral intLit{il_text = SourceText underscoredSrcTxt}}
     r = Replace Expr (toSSA x) [("a", toSSA y)] "a"
 suggestUnderscore x@(L _ (HsOverLit _ ol@(OverLit _ (HsFractional fracLit@(FL (SourceText srcTxt) _ _ _ _))))) =
   [ suggest "Use underscore" (reLoc x) (reLoc y) [r] | '_' `notElem` srcTxt, srcTxt /= underscoredSrcTxt ]
   where
     underscoredSrcTxt = addUnderscore srcTxt
+    y :: LocatedAn an (HsExpr GhcPs)
     y = noLocA $ HsOverLit EpAnnNotUsed $ ol{ol_val = HsFractional fracLit{fl_text = SourceText underscoredSrcTxt}}
     r = Replace Expr (toSSA x) [("a", toSSA y)] "a"
 suggestUnderscore _ = mempty
@@ -65,7 +75,9 @@
    chunkSize = if null (nl_prefix numLit) then 3 else 4
 
    underscore chunkSize = intercalate "_" . chunk chunkSize
-   underscoreFromRight chunkSize = reverse . underscore chunkSize . reverse
+   underscoreFromRight chunkSize str
+     | length str < 5 = str
+     | otherwise = reverse . underscore chunkSize . reverse $ str
    chunk chunkSize [] = []
    chunk chunkSize xs = a:chunk chunkSize b where (a, b) = splitAt chunkSize xs
 
diff --git a/src/Hint/Pattern.hs b/src/Hint/Pattern.hs
--- a/src/Hint/Pattern.hs
+++ b/src/Hint/Pattern.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE ViewPatterns, PatternGuards, TypeFamilies #-}
 
 {-
@@ -58,7 +59,7 @@
 
 module Hint.Pattern(patternHint) where
 
-import Hint.Type(DeclHint,Idea,modComments,ideaTo,toSSA,toRefactSrcSpan,suggest,suggestRemove,warn)
+import Hint.Type(DeclHint,Idea,modComments,firstDeclComments,ideaTo,toSSA,toRefactSrcSpan,suggest,suggestRemove,warn)
 import Data.Generics.Uniplate.DataOnly
 import Data.Function
 import Data.List.Extra
@@ -66,7 +67,7 @@
 import Data.Maybe
 import Data.Either
 import Refact.Types hiding (RType(Pattern, Match), SrcSpan)
-import qualified Refact.Types as R (RType(Pattern, Match), SrcSpan)
+import Refact.Types qualified as R (RType(Pattern, Match), SrcSpan)
 
 import GHC.Hs
 import GHC.Types.SrcLoc
@@ -74,7 +75,7 @@
 import GHC.Types.Name.Occurrence
 import GHC.Data.Bag
 import GHC.Types.Basic hiding (Pattern)
-import qualified GHC.Data.Strict
+import GHC.Data.Strict qualified
 
 import GHC.Util
 import Language.Haskell.GhclibParserEx.GHC.Hs.Pat
@@ -87,11 +88,16 @@
     concatMap (uncurry hints . swap) (asPattern x) ++
     -- PatBind (used in 'let' and 'where') contains lazy-by-default
     -- patterns, everything else is strict.
-    concatMap (patHint strict False) [p | PatBind _ p _ _ <- universeBi x :: [HsBind GhcPs]] ++
+    concatMap (patHint strict False) [p | PatBind _ p _ <- universeBi x :: [HsBind GhcPs]] ++
     concatMap (patHint strict True) (universeBi $ transformBi noPatBind x) ++
     concatMap expHint (universeBi x)
   where
-    exts = nubOrd $ concatMap snd (languagePragmas (pragmas (modComments modu))) -- language extensions enabled at source
+    -- Comments appearing without an empty line before the first
+    -- declaration in a module are now associated with the declaration
+    -- not the module so to be safe, look also at `firstDeclComments
+    -- modu`
+    -- (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
+    exts = nubOrd $ concatMap snd (languagePragmas (pragmas (modComments modu) ++ pragmas (firstDeclComments modu))) -- language extensions enabled at source
     strict = "Strict" `elem` exts
 
     noPatBind :: LHsBind GhcPs -> LHsBind GhcPs
@@ -184,8 +190,8 @@
 asPattern (L loc x) = concatMap decl (universeBi x)
   where
     decl :: HsBind GhcPs -> [(Pattern, String -> Pattern -> [Refactoring R.SrcSpan] -> Idea)]
-    decl o@(PatBind _ pat rhs _) = [(Pattern (locA loc) Bind [pat] rhs, \msg (Pattern _ _ [pat] rhs) rs -> suggest msg (noLoc o :: Located (HsBind GhcPs)) (noLoc (PatBind EpAnnNotUsed pat rhs ([], [])) :: Located (HsBind GhcPs)) rs)]
-    decl (FunBind _ _ (MG _ (L _ xs) _) _) = map match xs
+    decl o@(PatBind _ pat rhs) = [(Pattern (locA loc) Bind [pat] rhs, \msg (Pattern _ _ [pat] rhs) rs -> suggest msg (noLoc o :: Located (HsBind GhcPs)) (noLoc (PatBind EpAnnNotUsed pat rhs) :: Located (HsBind GhcPs)) rs)]
+    decl (FunBind _ _ (MG _ (L _ xs))) = map match xs
     decl _ = []
 
     match :: LMatch GhcPs (LHsExpr GhcPs) -> (Pattern, String -> Pattern -> [Refactoring R.SrcSpan] -> Idea)
@@ -208,7 +214,7 @@
   where
     f :: Pat GhcPs -> Bool
     f (ParPat _ _ (L _ x) _) = f x
-    f (AsPat _ _ (L _ x)) = f x
+    f (AsPat _ _ _ (L _ x)) = f x
     f LitPat {} = True
     f NPat {} = True
     f ConPat {} = True
@@ -222,22 +228,22 @@
   where
     f :: Pat GhcPs -> Bool
     f (ParPat _ _ (L _ x) _) = f x
-    f (AsPat _ _ (L _ x)) = f x
+    f (AsPat _ _ _ (L _ x)) = f x
     f WildPat{} = True
     f VarPat{} = True
     f _ = False
     r = Replace R.Pattern (toSSA o) [("x", toSSA pat)] "x"
-patHint _ _ o@(L _ (AsPat _ v (L _ (WildPat _)))) =
+patHint _ _ o@(L _ (AsPat _ v _ (L _ (WildPat _)))) =
   [warn "Redundant as-pattern" (reLoc o) (reLoc v) [Replace R.Pattern (toSSA o) [] (rdrNameStr v)]]
 patHint _ _ _ = []
 
 expHint :: LHsExpr GhcPs -> [Idea]
  -- Note the 'FromSource' in these equations (don't warn on generated match groups).
-expHint o@(L _ (HsCase _ _ (MG _ (L _ [L _ (Match _ CaseAlt [L _ (WildPat _)] (GRHSs _ [L _ (GRHS _ [] e)] (EmptyLocalBinds _))) ]) FromSource ))) =
+expHint o@(L _ (HsCase _ _ (MG FromSource (L _ [L _ (Match _ CaseAlt [L _ (WildPat _)] (GRHSs _ [L _ (GRHS _ [] e)] (EmptyLocalBinds _))) ])))) =
   [suggest "Redundant case" (reLoc o) (reLoc e) [r]]
   where
     r = Replace Expr (toSSA o) [("x", toSSA e)] "x"
-expHint o@(L _ (HsCase _ (L _ (HsVar _ (L _ x))) (MG _ (L _ [L _ (Match _ CaseAlt [L _ (VarPat _ (L _ y))] (GRHSs _ [L _ (GRHS _ [] e)] (EmptyLocalBinds _))) ]) FromSource )))
+expHint o@(L _ (HsCase _ (L _ (HsVar _ (L _ x))) (MG FromSource (L _ [L _ (Match _ CaseAlt [L _ (VarPat _ (L _ y))] (GRHSs _ [L _ (GRHS _ [] e)] (EmptyLocalBinds _))) ]))))
   | occNameStr x == occNameStr y =
       [suggest "Redundant case" (reLoc o) (reLoc e) [r]]
   where
diff --git a/src/Hint/Pragma.hs b/src/Hint/Pragma.hs
--- a/src/Hint/Pragma.hs
+++ b/src/Hint/Pragma.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE FlexibleContexts #-}
 
@@ -32,12 +33,12 @@
 
 module Hint.Pragma(pragmaHint) where
 
-import Hint.Type(ModuHint,Idea(..),Severity(..),toSSAnc,rawIdea,modComments)
+import Hint.Type(ModuHint,Idea(..),Severity(..),toSSAnc,rawIdea,modComments,firstDeclComments)
 import Data.List.Extra
-import qualified Data.List.NonEmpty as NE
+import Data.List.NonEmpty qualified as NE
 import Data.Maybe
 import Refact.Types
-import qualified Refact.Types as R
+import Refact.Types qualified as R
 
 import GHC.Hs
 import GHC.Types.SrcLoc
@@ -48,7 +49,11 @@
 
 pragmaHint :: ModuHint
 pragmaHint _ modu =
-  let ps = pragmas (modComments modu)
+  -- Comments appearing without a line-break before the first
+  -- declaration in a module are now associated with the declaration
+  -- not the module so to be safe, look also at `firstDeclComments
+  -- modu` (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
+  let ps = pragmas (modComments modu) ++ pragmas (firstDeclComments modu)
       opts = flags ps
       lang = languagePragmas ps in
     languageDupes lang ++ optToPragma opts lang
diff --git a/src/Hint/Restrict.hs b/src/Hint/Restrict.hs
--- a/src/Hint/Restrict.hs
+++ b/src/Hint/Restrict.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE TypeFamilies #-}
@@ -20,14 +21,14 @@
 </TEST>
 -}
 
-import Hint.Type(ModuHint,ModuleEx(..),Idea(..),Severity(..),warn,rawIdea,modComments)
+import Hint.Type(ModuHint,ModuleEx(..),Idea(..),Severity(..),warn,rawIdea,modComments,firstDeclComments)
 import Config.Type
 import Util
 
 import Data.Generics.Uniplate.DataOnly
-import qualified Data.List.NonEmpty as NonEmpty
-import qualified Data.Set as Set
-import qualified Data.Map as Map
+import Data.List.NonEmpty qualified as NonEmpty
+import Data.Set qualified as Set
+import Data.Map qualified as Map
 import Data.List.Extra
 import Data.List.NonEmpty (nonEmpty)
 import Data.Maybe
@@ -41,7 +42,6 @@
 
 import GHC.Hs
 import GHC.Types.Name.Reader
-import GHC.Unit.Module
 import GHC.Types.SrcLoc
 import GHC.Types.Name.Occurrence
 import Language.Haskell.GhclibParserEx.GHC.Hs
@@ -51,8 +51,14 @@
 -- FIXME: The settings should be partially applied, but that's hard to orchestrate right now
 restrictHint :: [Setting] -> ModuHint
 restrictHint settings scope m =
-    let anns = modComments m
-        ps   = pragmas anns
+    -- Comments appearing without an empty line before the first
+    -- declaration in a module are now associated with the declaration
+    -- not the module so to be safe, look also at `firstDeclComments
+    -- modu`
+    -- (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9517).
+    let annsMod = modComments m
+        annsFirstDecl = firstDeclComments m
+        ps   = pragmas annsMod ++ pragmas annsFirstDecl
         opts = flags ps
         exts = languagePragmas ps in
     checkPragmas modu opts exts rOthers ++
@@ -162,7 +168,7 @@
           Left $ ideaNoTo $ warn "Avoid restricted module" (reLoc i) (reLoc i) []
 
         let importedIdents = Set.fromList $
-              case ideclHiding of
+              case first (== EverythingBut) <$> ideclImportList of
                 Just (False, lxs) -> concatMap (importListToIdents . unLoc) (unLoc lxs)
                 _ -> []
             invalidIdents = case riRestrictIdents of
@@ -187,15 +193,15 @@
                   | otherwise -> (second (<> " or unqualified") <$> expectedQualStyle, Nothing)
                 ImportStyleQualified -> (expectedQualStyleDef, Nothing)
                 ImportStyleExplicitOrQualified
-                  | Just (False, _) <- ideclHiding -> (Nothing, Nothing)
+                  | Just (False, _) <- first (== EverythingBut) <$> ideclImportList -> (Nothing, Nothing)
                   | otherwise ->
                       ( second (<> " or with an explicit import list") <$> expectedQualStyleDef
                       , Nothing )
                 ImportStyleExplicit
-                  | Just (False, _) <- ideclHiding -> (Nothing, Nothing)
+                  | Just (False, _) <- first (== EverythingBut) <$> ideclImportList -> (Nothing, Nothing)
                   | otherwise ->
                       ( Just (NotQualified, "unqualified")
-                      , Just $ Just (False, noLocA []) )
+                      , Just $ Just (Exactly, noLocA []) )
                 ImportStyleUnqualified -> (Just (NotQualified, "unqualified"), Nothing)
             expectedQualStyleDef = expectedQualStyle <|> Just (QualifiedPre, "qualified")
             expectedQualStyle =
@@ -208,7 +214,7 @@
               | otherwise = expectedQual
         whenJust qualIdea $ \(qual, hint) -> do
           let i' = noLoc $ (unLoc i){ ideclQualified = qual
-                                    , ideclHiding = fromMaybe ideclHiding expectedHiding }
+                                    , ideclImportList = fromMaybe ideclImportList expectedHiding }
               msg = moduleNameString (unLoc ideclName) <> " should be imported " <> hint
           Left $ warn msg (reLoc i) i' []
 
@@ -237,10 +243,10 @@
         (IEThingWith _ n _ ns)   -> fromName n : map fromName ns
         _                        -> []
   where
-    fromName :: LIEWrappedName (IdP GhcPs) -> Maybe String
+    fromName :: LIEWrappedName GhcPs -> Maybe String
     fromName wrapped =
       case unLoc wrapped of
-        IEName      n -> fromId (unLoc n)
+        IEName    _ n -> fromId (unLoc n)
         IEPattern _ n -> ("pattern " ++) <$> fromId (unLoc n)
         IEType    _ n -> ("type " ++) <$> fromId (unLoc n)
 
diff --git a/src/Hint/Smell.hs b/src/Hint/Smell.hs
--- a/src/Hint/Smell.hs
+++ b/src/Hint/Smell.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 
 module Hint.Smell (smellModuleHint,smellHint) where
 
@@ -80,7 +81,7 @@
 
 import Data.Generics.Uniplate.DataOnly
 import Data.List.Extra
-import qualified Data.Map as Map
+import Data.Map qualified as Map
 
 import GHC.Utils.Outputable
 import GHC.Types.Basic
@@ -128,7 +129,7 @@
 declSpans
    (L _ (ValD _
      FunBind {fun_matches=MG {
-                   mg_origin=FromSource
+                   mg_ext=FromSource
                  , mg_alts=(L _ [L _ Match {
                        m_ctxt=ctx
                      , m_grhss=GRHSs{grhssGRHSs=[locGrhs]
diff --git a/src/Hint/Unsafe.hs b/src/Hint/Unsafe.hs
--- a/src/Hint/Unsafe.hs
+++ b/src/Hint/Unsafe.hs
@@ -54,8 +54,8 @@
      -- 'x' does not declare a new function.
      | d@(ValD _
            FunBind {fun_id=L _ (Unqual x)
-                      , fun_matches=MG{mg_origin=FromSource,mg_alts=L _ [L _ Match {m_pats=[]}]}}) <- [d]
-     -- 'x' is a synonym for an appliciation involing 'unsafePerformIO'
+                      , fun_matches=MG{mg_ext=FromSource,mg_alts=L _ [L _ Match {m_pats=[]}]}}) <- [d]
+     -- 'x' is a synonym for an application involving 'unsafePerformIO'
      , isUnsafeDecl d
      -- 'x' is not marked 'NOINLINE'.
      , x `notElem` noinline]
@@ -70,7 +70,7 @@
         ) <- hsmodDecls m]
 
 isUnsafeDecl :: HsDecl GhcPs -> Bool
-isUnsafeDecl (ValD _ FunBind {fun_matches=MG {mg_origin=FromSource,mg_alts=L _ alts}}) =
+isUnsafeDecl (ValD _ FunBind {fun_matches=MG {mg_ext=FromSource,mg_alts=L _ alts}}) =
   any isUnsafeApp (childrenBi alts) || any isUnsafeDecl (childrenBi alts)
 isUnsafeDecl _ = False
 
diff --git a/src/Idea.hs b/src/Idea.hs
--- a/src/Idea.hs
+++ b/src/Idea.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE RecordWildCards, NoMonomorphismRestriction #-}
 
 module Idea(
@@ -13,7 +14,7 @@
 import Config.Type
 import HsColour
 import Refact.Types hiding (SrcSpan)
-import qualified Refact.Types as R
+import Refact.Types qualified as R
 import Prelude
 import GHC.Types.SrcLoc
 import GHC.Utils.Outputable
@@ -36,7 +37,7 @@
     deriving Eq
 
 -- I don't use aeson here for 2 reasons:
--- 1) Aeson doesn't esape unicode characters, and I want to (allows me to ignore encoding)
+-- 1) Aeson doesn't escape unicode characters, and I want to (allows me to ignore encoding)
 -- 2) I want to control the format so it's slightly human readable as well
 showIdeaJson :: Idea -> String
 showIdeaJson idea@Idea{ideaSpan=srcSpan@SrcSpan{..}, ..} = dict
diff --git a/src/Language/Haskell/HLint.hs b/src/Language/Haskell/HLint.hs
--- a/src/Language/Haskell/HLint.hs
+++ b/src/Language/Haskell/HLint.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE PatternGuards, RecordWildCards #-}
 
 -- |  This module provides a way to apply HLint hints. If you want to just run @hlint@ in-process
@@ -33,13 +34,13 @@
 import Config.Type
 import Config.Read
 import Idea
-import qualified Apply as H
+import Apply qualified as H
 import HLint
 import Fixity
 import GHC.Data.FastString ( unpackFS )
 import GHC.All
 import Hint.All hiding (resolveHints)
-import qualified Hint.All as H
+import Hint.All qualified as H
 import GHC.Types.SrcLoc
 import CmdLine
 import Paths_hlint
@@ -49,7 +50,7 @@
 import System.FilePath
 import Data.Functor
 import Prelude
-import qualified Hint.Restrict as Restrict
+import Hint.Restrict qualified as Restrict
 
 
 -- | Get the Cabal configured data directory of HLint.
@@ -57,7 +58,7 @@
 getHLintDataDir = getDataDir
 
 
--- | The function produces a tuple containg 'ParseFlags' (for 'parseModuleEx'),
+-- | The function produces a tuple containing 'ParseFlags' (for 'parseModuleEx'),
 --   and 'Classify' and 'Hint' for 'applyHints'.
 --   It approximates the normal HLint configuration steps, roughly:
 --
@@ -144,7 +145,7 @@
 --
 -- > (filename, (startLine, startCol), (endLine, endCol))
 --
---   Following the GHC API, he end column is the column /after/ the end of the error.
+--   Following the GHC API, end column is the column /after/ the end of the error.
 --   Lines and columns are 1-based. Returns 'Nothing' if there is no helpful location information.
 unpackSrcSpan :: SrcSpan -> Maybe (FilePath, (Int, Int), (Int, Int))
 unpackSrcSpan (RealSrcSpan x _) = Just
diff --git a/src/Refact.hs b/src/Refact.hs
--- a/src/Refact.hs
+++ b/src/Refact.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE LambdaCase #-}
 
 module Refact
@@ -17,10 +18,10 @@
 import System.Exit
 import System.IO.Extra
 import System.Process.Extra
-import qualified Refact.Types as R
+import Refact.Types qualified as R
 
-import qualified GHC.Types.SrcLoc as GHC
-import qualified GHC.Parser.Annotation as GHC
+import GHC.Types.SrcLoc qualified as GHC
+import GHC.Parser.Annotation qualified as GHC
 
 import GHC.Util.SrcLoc (getAncLoc)
 
diff --git a/src/Report.hs b/src/Report.hs
--- a/src/Report.hs
+++ b/src/Report.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE RecordWildCards #-}
 
 module Report(writeReport) where
@@ -5,14 +6,14 @@
 import Idea
 import Data.Tuple.Extra
 import Data.List.Extra
-import qualified Data.List.NonEmpty as NE
+import Data.List.NonEmpty qualified as NE
 import Data.Maybe
 import Data.Version
 import Timing
 import Paths_hlint
 import HsColour
 import EmbedData
-import qualified GHC.Util as GHC
+import GHC.Util qualified as GHC
 
 
 writeTemplate :: FilePath -> [(String,[String])] -> FilePath -> IO ()
diff --git a/src/SARIF.hs b/src/SARIF.hs
new file mode 100644
--- /dev/null
+++ b/src/SARIF.hs
@@ -0,0 +1,178 @@
+{-# LANGUAGE ImportQualifiedPost #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecordWildCards #-}
+
+{- |
+Description: Formats hlint ideas in the Statis Analysis Results Interchange Format (SARIF).
+License: BSD-3-Clause
+
+Supports the conversion of a list of HLint 'Idea's into SARIF.
+
+SARIF (Static Analysis Results Interchange Format) is an open interchange format
+for storing results from static analyses.
+-}
+module SARIF ( printIdeas
+             , showIdeas
+             , toJSONEncoding
+             -- * See also
+             --
+             -- $references
+             ) where
+
+import Data.Aeson hiding (Error)
+import Data.Aeson.Encoding
+import Data.ByteString.Lazy (ByteString)
+import Data.ByteString.Lazy qualified as B
+import Data.Text.Lazy (Text)
+import Data.Version (showVersion)
+import GHC.Util
+import Idea
+import Paths_hlint (version)
+
+-- | Print the given ideas to standard output.
+--
+-- For example:
+--
+-- >>> hlint ["src"] >>= printIdeas
+--
+-- For printing ideas in SARIF without dependent modules
+-- having to import "Data.Aeson" or "Data.ByteString.Lazy".
+printIdeas :: [Idea] -> IO ()
+printIdeas = B.putStr . showIdeas
+
+-- | Format the given ideas in SARIF.
+--
+-- For converting ideas to SARIF without dependent modules
+-- having to import "Data.Aeson".
+showIdeas :: [Idea] -> ByteString
+showIdeas = encodingToLazyByteString . toJSONEncoding
+
+-- | Converts the given ideas to a "Data.Aeson" encoding in SARIF.
+toJSONEncoding :: [Idea] -> Encoding
+toJSONEncoding = pairs . sarif
+
+-- | Converts the given object to a top-level @sarifLog@ object.
+--
+-- See section 3.13 "sarifLog object", SARIF specification.
+sarif :: [Idea] -> Series
+sarif ideas =
+  pair "version" (lazyText "2.1.0") <>
+  pair "$schema" (lazyText schemaURI) <>
+  pair "runs" runs
+  where runs = list pairs [ pair "tool" (pairs tool) <>
+                            pair "results" (list (pairs . toResult) ideas) ]
+
+-- | A @tool@ object describing what created the output.
+--
+-- Obviously, it will describe that HLint created the output.
+--
+-- See section 3.18 "tool object", SARIF specification.
+tool :: Series
+tool = pair "driver" $ pairs $
+  pair "name" (lazyText "hlint") <>
+  pair "version" (string $ showVersion version) <>
+  pair "informationUri" (lazyText hlintURI)
+
+-- | Converts a given idea into a @result@ object.
+--
+-- It will describe the hint, the severity, suggestions for fixes, etc.
+--
+-- See section 3.27 "result object", SARIF specification.
+toResult :: Idea -> Series
+toResult idea@Idea{..} =
+  pair "message" (pairs $ pair "text" $ string $ show idea) <>
+  pair "level" (lazyText $ showSeverity ideaSeverity) <>
+  pair "locations" (list (pairs . toLocation) [idea]) <>
+  pair "fixes" (list (pairs . toFix) [idea]) <>
+  -- Use 'ideaHint' as the rule identifier.
+  --
+  -- "ruleId" is supposed to a stable, opaque identifier.
+  -- 'ideaHint' is not opaque, nor is it quite guaranteed to be stable,
+  -- but they will usually be stable enough, and disabling a hint is
+  -- based on the name in 'ideaHint'.
+  --
+  -- Most importantly, there is no requirement that "ruleId"
+  -- be a /unique/ identifier.
+  pair "ruleId" (string ideaHint)
+
+-- | Convert HLint severity to SARIF level.
+--
+-- See section 3.58.6 "level property", SARIF specification.
+showSeverity :: Severity -> Text
+showSeverity Error = "error"
+showSeverity Warning = "warning"
+showSeverity Suggestion = "note"
+showSeverity Ignore = "none"
+
+-- | Converts the location information in a given idea to a @location@ object.
+--
+-- See section 3.28 "location object", SARIF specification.
+toLocation :: Idea -> Series
+toLocation idea@Idea{ideaSpan=SrcSpan{..}, ..} =
+  physicalLocation <> logicalLocations ideaModule ideaDecl
+  where physicalLocation = pair "physicalLocation" $ pairs $
+          pair "artifactLocation"
+              (pairs $ pair "uri" (string srcSpanFilename)) <>
+          pair "region" (pairs $ toRegion idea)
+
+        logicalLocations [mod] [decl] = pair "logicalLocations" $
+          list pairs [ pair "name" (string decl) <>
+                       pair "fullyQualifiedName" (string $ mod ++ "." ++ decl) ]
+          -- It would be nice to include whether it is a function or type
+          -- in the "kind" field, but we do not have that information.
+
+        -- If the lists are empty, then there is obviously no logical location.
+        -- Logical location is still omitted when the lists are not singleton,
+        -- because the associations between modules and declarations are
+        -- not clear.
+        logicalLocations _ _ = mempty
+
+-- | Converts a given idea to a @fix@ object.
+--
+-- It will suggest how code can be improved to deal with an issue.
+-- This includes the file to be changed and how to change it.
+--
+-- See section 3.55 "fix object", SARIF specification.
+toFix :: Idea -> Series
+toFix idea@Idea{..} =
+  pair "description" (pairs $ pair "text" $ string ideaHint) <>
+  pair "artifactChanges" (list (pairs . toChange) [idea])
+
+-- | Converts a given idea to a @artifactChange@ object.
+--
+-- It will describe the details as to how the code can be changed.
+-- I.e., the text to remove and what it should be replaced with.
+--
+-- See section 3.56 "artifactChange object", SARIF specification.
+toChange :: Idea -> Series
+toChange idea@Idea{ideaSpan=SrcSpan{..}, ..} =
+  pair "artifactLocation" (pairs uri) <>
+  pair "replacements" (list pairs [deleted <> inserted])
+  where uri  = pair "uri" $ string srcSpanFilename
+        deleted = pair "deletedRegion" $ pairs $ toRegion idea
+        inserted = maybe mempty insertedContent ideaTo
+        insertedContent = pair "insertedContent" . pairs . pair "text" . string
+
+-- | Converts the source span in an idea to a SARIF region.
+--
+-- See 3.30 "region object", SARIF specification.
+toRegion :: Idea -> Series
+toRegion Idea{ideaSpan=SrcSpan{..}, ..} =
+  pair "startLine" (int srcSpanStartLine') <>
+  pair "startColumn" (int srcSpanStartColumn) <>
+  pair "endLine" (int srcSpanEndLine') <>
+  pair "endColumn" (int srcSpanEndColumn)
+
+-- | URI to SARIF schema definition.
+schemaURI :: Text
+schemaURI = "https://raw.githubusercontent.com/" <>
+            "oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json"
+
+-- | URI to HLint home page.
+hlintURI :: Text
+hlintURI = "https://github.com/ndmitchell/hlint"
+
+-- $references
+--
+-- * [SARIF Tutorials](https://github.com/microsoft/sarif-tutorials)
+-- * [Static Analysis Results Interchange Format](https://docs.oasis-open.org/sarif/sarif/v2.1.0/cs01/sarif-v2.1.0-cs01.html), version 2.1.0
diff --git a/src/Summary.hs b/src/Summary.hs
--- a/src/Summary.hs
+++ b/src/Summary.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DerivingVia #-}
@@ -5,7 +6,7 @@
 
 module Summary (generateMdSummary, generateJsonSummary, generateExhaustiveConfig) where
 
-import qualified Data.Map as Map
+import Data.Map qualified as Map
 import Control.Monad.Extra
 import System.FilePath
 import Data.List.Extra
diff --git a/src/Test/Annotations.hs b/src/Test/Annotations.hs
--- a/src/Test/Annotations.hs
+++ b/src/Test/Annotations.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 {-# LANGUAGE CPP, PatternGuards, RecordWildCards, ViewPatterns #-}
 
 -- | Check the <TEST> annotations within source and hint files.
@@ -17,7 +18,7 @@
 import System.FilePath
 import System.IO.Extra
 import GHC.All
-import qualified Data.ByteString.Char8 as BS
+import Data.ByteString.Char8 qualified as BS
 
 import Config.Type
 import Idea
@@ -163,7 +164,7 @@
 testRefactor Nothing _ _ = pure []
 -- Skip refactoring test if there is no hint.
 testRefactor _ Nothing _ = pure []
--- Skip refactoring test if the hint has no suggestion (such as "Parse error" or "Avoid restricted fuction").
+-- Skip refactoring test if the hint has no suggestion (such as "Parse error" or "Avoid restricted function").
 testRefactor _ (Just idea) _ | isNothing (ideaTo idea) = pure []
 -- Skip refactoring test if the hint does not support refactoring.
 testRefactor _ (Just idea) _ | null (ideaRefactoring idea) = pure []
diff --git a/src/Test/InputOutput.hs b/src/Test/InputOutput.hs
--- a/src/Test/InputOutput.hs
+++ b/src/Test/InputOutput.hs
@@ -17,6 +17,8 @@
 import System.Exit
 import System.IO.Extra
 import Prelude
+import Data.Version (showVersion)
+import Paths_hlint (version)
 
 import Test.Util
 
@@ -48,6 +50,8 @@
     where
         z = InputOutput "unknown" [] [] "" Nothing
         interest x = any (`isPrefixOf` x) ["----","FILE","RUN","OUTPUT","EXIT"]
+        outputTemplateVars = [ ("__VERSION__", showVersion version) ]
+        substituteTemplateVars = mconcatMap (uncurry replace) outputTemplateVars
 
         f io ((stripPrefix "RUN " -> Just flags):xs) = f io{run = splitArgs flags} xs
         f io ((stripPrefix "EXIT " -> Just code):xs) = f io{exit = Just $ let i = read code in if i == 0 then ExitSuccess else ExitFailure i} xs
@@ -57,7 +61,7 @@
         f io [] = [io | io /= z]
         f io (x:xs) = error $ "Unknown test item, " ++ x
 
-        g = first (reverse . dropWhile null . reverse) . break interest
+        g = first (fmap substituteTemplateVars . reverse . dropWhile null . reverse) . break interest
 
 
 ---------------------------------------------------------------------
diff --git a/src/Timing.hs b/src/Timing.hs
--- a/src/Timing.hs
+++ b/src/Timing.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ImportQualifiedPost #-}
 
 module Timing(
     timed, timedIO,
@@ -5,7 +6,7 @@
     printTimings
     ) where
 
-import qualified Data.HashMap.Strict as Map
+import Data.HashMap.Strict qualified as Map
 import Control.Exception
 import Data.IORef.Extra
 import Data.Tuple.Extra
diff --git a/tests/cpp.test b/tests/cpp.test
--- a/tests/cpp.test
+++ b/tests/cpp.test
@@ -44,7 +44,8 @@
 main = undefined
 EXIT 1
 OUTPUT
-tests/cpp-ext-enable.hs:1:1: Error: Parse error: tests/cpp-ext-enable.hs:3:14: error: Unsupported extension: Foo
+tests/cpp-ext-enable.hs:1:1: Error: Parse error: tests/cpp-ext-enable.hs:3:14: error: [GHC-46537]
+    Unsupported extension: Foo
 Found:
   {-# LANGUAGE CPP #-}
 
@@ -52,7 +53,7 @@
 
   main = undefined
 
-1 hint
+1 error
 
 ---------------------------------------------------------------------
 RUN tests/cpp-ext-disable.hs
@@ -128,3 +129,39 @@
 #endif
 OUTPUT
 No hints
+
+---------------------------------------------------------------------
+RUN tests/cpp-file5.hs
+FILE tests/cpp-file5.hs
+{-# LANGUAGE CPP #-}
+main =
+#if __GLASGOW_HASKELL__ > 800
+  print __GLASGOW_HASKELL__
+#else
+  putStrLn $ show __GLASGOW_HASKELL__
+#endif
+OUTPUT
+tests/cpp-file5.hs:1:1-20: Warning: Avoid restricted extensions
+Found:
+  {-# LANGUAGE CPP #-}
+Note: may break the code
+
+1 hint
+
+---------------------------------------------------------------------
+RUN --cpp-define "__GLASGOW_HASKELL__=123" tests/cpp-file6.hs
+FILE tests/cpp-file6.hs
+{-# LANGUAGE CPP #-}
+main =
+#if __GLASGOW_HASKELL__ == 123
+  print __GLASGOW_HASKELL__
+#else
+  putStrLn $ show __GLASGOW_HASKELL__
+#endif
+OUTPUT
+tests/cpp-file6.hs:1:1-20: Warning: Avoid restricted extensions
+Found:
+  {-# LANGUAGE CPP #-}
+Note: may break the code
+
+1 hint
diff --git a/tests/do-block.test b/tests/do-block.test
new file mode 100644
--- /dev/null
+++ b/tests/do-block.test
@@ -0,0 +1,17 @@
+---------------------------------------------------------------------
+RUN tests/do-block.hs --hint=data/do-block.yaml
+FILE tests/do-block.hs
+h x = case f x of
+  Just n -> g n
+  Nothing -> Nothing
+OUTPUT
+tests/do-block.hs:(1,7)-(3,20): Warning: Redundant Nothing
+Found:
+  case f x of
+    Just n -> g n
+    Nothing -> Nothing
+Perhaps:
+  do n <- f x
+     g n
+
+1 hint
diff --git a/tests/flag-ignore-suggestions.test b/tests/flag-ignore-suggestions.test
new file mode 100644
--- /dev/null
+++ b/tests/flag-ignore-suggestions.test
@@ -0,0 +1,38 @@
+---------------------------------------------------------------------
+RUN tests/flag-ignore-suggestions-1.hs --ignore-suggestions
+FILE tests/flag-ignore-suggestions-1.hs
+main = map f $ map g xs
+OUTPUT
+No hints
+
+EXIT 0
+---------------------------------------------------------------------
+RUN tests/flag-ignore-suggestions-2.hs --ignore-suggestions
+FILE tests/flag-ignore-suggestions-2.hs
+foo = (+1)
+bar x = foo x
+main = map f $ map g xs
+OUTPUT
+tests/flag-ignore-suggestions-2.hs:2:1-13: Warning: Eta reduce
+Found:
+  bar x = foo x
+Perhaps:
+  bar = foo
+
+1 hint
+
+EXIT 1
+---------------------------------------------------------------------
+RUN tests/flag-ignore-suggestions-3.hs --ignore-suggestions --show
+FILE tests/flag-ignore-suggestions-3.hs
+main = map f $ map g xs
+OUTPUT
+tests/flag-ignore-suggestions-3.hs:1:8-23: Suggestion: Use map once
+Found:
+  map f $ map g xs
+Perhaps:
+  map (f . g) xs
+
+1 hint
+
+EXIT 1
diff --git a/tests/lhs.test b/tests/lhs.test
--- a/tests/lhs.test
+++ b/tests/lhs.test
@@ -31,7 +31,7 @@
 
   >
 
-1 hint
+1 error
 
 ---------------------------------------------------------------------
 RUN tests/lhs-first-line.lhs
diff --git a/tests/parse-error.test b/tests/parse-error.test
--- a/tests/parse-error.test
+++ b/tests/parse-error.test
@@ -18,16 +18,16 @@
 
   > where
 
-1 hint
+1 error
 
 ---------------------------------------------------------------------
 RUN tests/ignore-parse-error3.hs
 FILE tests/ignore-parse-error3.hs
 {-# LANGUAGE InvalidExtension #-}
 OUTPUT
-tests/ignore-parse-error3.hs:1:1: Error: Parse error: tests/ignore-parse-error3.hs:1:14: error:
+tests/ignore-parse-error3.hs:1:1: Error: Parse error: tests/ignore-parse-error3.hs:1:14: error: [GHC-46537]
     Unsupported extension: InvalidExtension
 Found:
   {-# LANGUAGE InvalidExtension #-}
 
-1 hint
+1 error
diff --git a/tests/sarif.test b/tests/sarif.test
new file mode 100644
--- /dev/null
+++ b/tests/sarif.test
@@ -0,0 +1,38 @@
+---------------------------------------------------------------------
+RUN tests/sarif-none.hs --sarif
+FILE tests/sarif-none.hs
+foo = (+1)
+OUTPUT
+{"version":"2.1.0","$schema":"https://raw.githubusercontent.com/oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json","runs":[{"tool":{"driver":{"name":"hlint","version":"__VERSION__","informationUri":"https://github.com/ndmitchell/hlint"}},"results":[]}]}
+
+---------------------------------------------------------------------
+RUN tests/sarif-one.hs --sarif
+FILE tests/sarif-one.hs
+foo = (+1)
+bar x = foo x
+OUTPUT
+{"version":"2.1.0","$schema":"https://raw.githubusercontent.com/oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json","runs":[{"tool":{"driver":{"name":"hlint","version":"__VERSION__","informationUri":"https://github.com/ndmitchell/hlint"}},"results":[{"message":{"text":"tests/sarif-one.hs:2:1-13: Warning: Eta reduce\nFound:\n  bar x = foo x\nPerhaps:\n  bar = foo\n"},"level":"warning","locations":[{"physicalLocation":{"artifactLocation":{"uri":"tests/sarif-one.hs"},"region":{"startLine":2,"startColumn":1,"endLine":2,"endColumn":14}},"logicalLocations":[{"name":"bar","fullyQualifiedName":"Main.bar"}]}],"fixes":[{"description":{"text":"Eta reduce"},"artifactChanges":[{"artifactLocation":{"uri":"tests/sarif-one.hs"},"replacements":[{"deletedRegion":{"startLine":2,"startColumn":1,"endLine":2,"endColumn":14},"insertedContent":{"text":"bar = foo"}}]}]}],"ruleId":"Eta reduce"}]}]}
+
+---------------------------------------------------------------------
+RUN tests/sarif-two.hs --sarif
+FILE tests/sarif-two.hs
+foo = (+1)
+bar x = foo x
+baz = getLine >>= pure . upper
+OUTPUT
+{"version":"2.1.0","$schema":"https://raw.githubusercontent.com/oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json","runs":[{"tool":{"driver":{"name":"hlint","version":"__VERSION__","informationUri":"https://github.com/ndmitchell/hlint"}},"results":[{"message":{"text":"tests/sarif-two.hs:2:1-13: Warning: Eta reduce\nFound:\n  bar x = foo x\nPerhaps:\n  bar = foo\n"},"level":"warning","locations":[{"physicalLocation":{"artifactLocation":{"uri":"tests/sarif-two.hs"},"region":{"startLine":2,"startColumn":1,"endLine":2,"endColumn":14}},"logicalLocations":[{"name":"bar","fullyQualifiedName":"Main.bar"}]}],"fixes":[{"description":{"text":"Eta reduce"},"artifactChanges":[{"artifactLocation":{"uri":"tests/sarif-two.hs"},"replacements":[{"deletedRegion":{"startLine":2,"startColumn":1,"endLine":2,"endColumn":14},"insertedContent":{"text":"bar = foo"}}]}]}],"ruleId":"Eta reduce"},{"message":{"text":"tests/sarif-two.hs:3:7-30: Suggestion: Use <&>\nFound:\n  getLine >>= pure . upper\nPerhaps:\n  getLine Data.Functor.<&> upper\n"},"level":"note","locations":[{"physicalLocation":{"artifactLocation":{"uri":"tests/sarif-two.hs"},"region":{"startLine":3,"startColumn":7,"endLine":3,"endColumn":31}},"logicalLocations":[{"name":"baz","fullyQualifiedName":"Main.baz"}]}],"fixes":[{"description":{"text":"Use <&>"},"artifactChanges":[{"artifactLocation":{"uri":"tests/sarif-two.hs"},"replacements":[{"deletedRegion":{"startLine":3,"startColumn":7,"endLine":3,"endColumn":31},"insertedContent":{"text":"getLine Data.Functor.<&> upper"}}]}]}],"ruleId":"Use <&>"}]}]}
+
+---------------------------------------------------------------------
+RUN tests/sarif-parse-error.hs --sarif
+FILE tests/sarif-parse-error.hs
+@
+OUTPUT
+{"version":"2.1.0","$schema":"https://raw.githubusercontent.com/oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json","runs":[{"tool":{"driver":{"name":"hlint","version":"__VERSION__","informationUri":"https://github.com/ndmitchell/hlint"}},"results":[{"message":{"text":"tests/sarif-parse-error.hs:1:1: Error: Parse error: on input `@'\nFound:\n  > @\n"},"level":"error","locations":[{"physicalLocation":{"artifactLocation":{"uri":"tests/sarif-parse-error.hs"},"region":{"startLine":1,"startColumn":1,"endLine":1,"endColumn":2}}}],"fixes":[{"description":{"text":"Parse error: on input `@'"},"artifactChanges":[{"artifactLocation":{"uri":"tests/sarif-parse-error.hs"},"replacements":[{"deletedRegion":{"startLine":1,"startColumn":1,"endLine":1,"endColumn":2}}]}]}],"ruleId":"Parse error: on input `@'"}]}]}
+
+---------------------------------------------------------------------
+RUN tests/sarif-note.hs --sarif
+FILE tests/sarif-note.hs
+foo = any (a ==)
+bar = foldl (&&) True
+OUTPUT
+{"version":"2.1.0","$schema":"https://raw.githubusercontent.com/oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json","runs":[{"tool":{"driver":{"name":"hlint","version":"__VERSION__","informationUri":"https://github.com/ndmitchell/hlint"}},"results":[{"message":{"text":"tests/sarif-note.hs:1:7-16: Warning: Use elem\nFound:\n  any (a ==)\nPerhaps:\n  elem a\n"},"level":"warning","locations":[{"physicalLocation":{"artifactLocation":{"uri":"tests/sarif-note.hs"},"region":{"startLine":1,"startColumn":7,"endLine":1,"endColumn":17}},"logicalLocations":[{"name":"foo","fullyQualifiedName":"Main.foo"}]}],"fixes":[{"description":{"text":"Use elem"},"artifactChanges":[{"artifactLocation":{"uri":"tests/sarif-note.hs"},"replacements":[{"deletedRegion":{"startLine":1,"startColumn":7,"endLine":1,"endColumn":17},"insertedContent":{"text":"elem a"}}]}]}],"ruleId":"Use elem"},{"message":{"text":"tests/sarif-note.hs:2:7-21: Warning: Use and\nFound:\n  foldl (&&) True\nPerhaps:\n  and\nNote: increases laziness\n"},"level":"warning","locations":[{"physicalLocation":{"artifactLocation":{"uri":"tests/sarif-note.hs"},"region":{"startLine":2,"startColumn":7,"endLine":2,"endColumn":22}},"logicalLocations":[{"name":"bar","fullyQualifiedName":"Main.bar"}]}],"fixes":[{"description":{"text":"Use and"},"artifactChanges":[{"artifactLocation":{"uri":"tests/sarif-note.hs"},"replacements":[{"deletedRegion":{"startLine":2,"startColumn":7,"endLine":2,"endColumn":22},"insertedContent":{"text":"and"}}]}]}],"ruleId":"Use and"}]}]}
diff --git a/tests/serialise.test b/tests/serialise.test
--- a/tests/serialise.test
+++ b/tests/serialise.test
@@ -40,7 +40,6 @@
 [("tests/serialise-four.hs:2:1-20: Warning: Use fewer LANGUAGE pragmas\nFound:\n  {-# LANGUAGE CPP #-}\n  {-# LANGUAGE CPP #-}\nPerhaps:\n  {-# LANGUAGE CPP #-}\n",[ModifyComment {pos = SrcSpan {startLine = 2, startCol = 1, endLine = 2, endCol = 21}, newComment = "{-# LANGUAGE CPP #-}"},ModifyComment {pos = SrcSpan {startLine = 1, startCol = 1, endLine = 1, endCol = 21}, newComment = ""}])]
 
 
-
 ---------------------------------------------------------------------
 RUN tests/serialise-five.hs --serialise
 FILE tests/serialise-five.hs