diff --git a/hledger-lib/Hledger/Data/Dates.hs b/hledger-lib/Hledger/Data/Dates.hs
index 775c6d887..9236d783d 100644
--- a/hledger-lib/Hledger/Data/Dates.hs
+++ b/hledger-lib/Hledger/Data/Dates.hs
@@ -840,7 +840,7 @@ weekday = do
                          show wday <> " in " <> show (weekdays ++ weekdayabbrevs)
 
 weekdaysp :: TextParser m [Int]
-weekdaysp = fmap head . groupBy (==) . sort <$> sepBy1 weekday (string' ",")
+weekdaysp = fmap head . group . sort <$> sepBy1 weekday (string' ",")
 
 -- | Parse a period expression, specifying a date span and optionally
 -- a reporting interval. Requires a reference "today" date for
diff --git a/hledger-lib/Hledger/Query.hs b/hledger-lib/Hledger/Query.hs
index df0ea8921..110f5d84a 100644
--- a/hledger-lib/Hledger/Query.hs
+++ b/hledger-lib/Hledger/Query.hs
@@ -183,7 +183,7 @@ parseQuery d = parseQueryList d . words'' prefixes
 -- 4. then all terms are AND'd together
 parseQueryList :: Day -> [T.Text] -> Either String (Query, [QueryOpt])
 parseQueryList d termstrs = do
-  eterms <- sequence $ map (parseQueryTerm d) termstrs
+  eterms <- mapM (parseQueryTerm d) termstrs
   let (pats, opts) = partitionEithers eterms
       (descpats, pats') = partition queryIsDesc pats
       (acctpats, pats'') = partition queryIsAcct pats'
@@ -361,14 +361,14 @@ simplifyQuery q =
     simplify (And []) = Any
     simplify (And [q]) = simplify q
     simplify (And qs) | same qs = simplify $ head qs
-                      | any (==None) qs = None
+                      | None `elem` qs = None
                       | all queryIsDate qs = Date $ spansIntersect $ mapMaybe queryTermDateSpan qs
                       | otherwise = And $ concat $ [map simplify dateqs, map simplify otherqs]
                       where (dateqs, otherqs) = partition queryIsDate $ filter (/=Any) qs
     simplify (Or []) = Any
     simplify (Or [q]) = simplifyQuery q
     simplify (Or qs) | same qs = simplify $ head qs
-                     | any (==Any) qs = Any
+                     | Any `elem` qs = Any
                      -- all queryIsDate qs = Date $ spansUnion $ mapMaybe queryTermDateSpan qs  ?
                      | otherwise = Or $ map simplify $ filter (/=None) qs
     simplify (Date (DateSpan Nothing Nothing)) = Any
@@ -445,8 +445,8 @@ queryIsStatus _ = False
 queryIsStartDateOnly :: Bool -> Query -> Bool
 queryIsStartDateOnly _ Any = False
 queryIsStartDateOnly _ None = False
-queryIsStartDateOnly secondary (Or ms) = and $ map (queryIsStartDateOnly secondary) ms
-queryIsStartDateOnly secondary (And ms) = and $ map (queryIsStartDateOnly secondary) ms
+queryIsStartDateOnly secondary (Or ms) = all (queryIsStartDateOnly secondary) ms
+queryIsStartDateOnly secondary (And ms) = all (queryIsStartDateOnly secondary) ms
 queryIsStartDateOnly False (Date (DateSpan (Just _) _)) = True
 queryIsStartDateOnly True (Date2 (DateSpan (Just _) _)) = True
 queryIsStartDateOnly _ _ = False
@@ -613,7 +613,7 @@ matchesPosting (StatusQ s) p = postingStatus p == s
 matchesPosting (Real v) p = v == isReal p
 matchesPosting q@(Depth _) Posting{paccount=a} = q `matchesAccount` a
 matchesPosting q@(Amt _ _) Posting{pamount=as} = q `matchesMixedAmount` as
-matchesPosting (Sym r) Posting{pamount=as} = any (matchesCommodity (Sym r)) . map acommodity $ amountsRaw as
+matchesPosting (Sym r) Posting{pamount=as} = any (matchesCommodity (Sym r) . acommodity) $ amountsRaw as
 matchesPosting (Tag n v) p = case (reString n, v) of
   ("payee", Just v) -> maybe False (regexMatchText v . transactionPayee) $ ptransaction p
   ("note", Just v) -> maybe False (regexMatchText v . transactionNote) $ ptransaction p
diff --git a/hledger-lib/Hledger/Reports/BudgetReport.hs b/hledger-lib/Hledger/Reports/BudgetReport.hs
index d28a10de6..af88601bf 100644
--- a/hledger-lib/Hledger/Reports/BudgetReport.hs
+++ b/hledger-lib/Hledger/Reports/BudgetReport.hs
@@ -257,7 +257,7 @@ budgetReportAsTable
 
     addtotalrow
       | no_total_ = id
-      | otherwise = let rh = Tab.Group NoLine $ map Header (replicate (length totalrows) "")
+      | otherwise = let rh = Tab.Group NoLine . replicate (length totalrows) $ Header ""
                         ch = Header [] -- ignored
                      in (flip (concatTables SingleLine) $ Table rh ch totalrows)
 
@@ -279,7 +279,7 @@ budgetReportAsTable
         showntr    = [showrow $ rowToBudgetCells tr]
         (trcs, trtexts)         = unzip  $ concat showntr
         trwidths
-          | transpose_ = snd $ splitAt (length texts) widths
+          | transpose_ = drop (length texts) widths
           | otherwise = widths
 
         padcells = maybetranspose . fmap (fmap (uncurry paddisplaycell) . zip widths)   . maybetranspose
@@ -334,7 +334,7 @@ budgetReportAsTable
         actualwidths  = map (maximum' . map first3 ) $ cols
         budgetwidths  = map (maximum' . map second3) $ cols
         percentwidths = map (maximum' . map third3 ) $ cols
-        catcolumnwidths = foldl (\l a -> zipWith (++) l a) (repeat [])
+        catcolumnwidths = foldl' (zipWith (++)) $ repeat []
         cols = maybetranspose $ catcolumnwidths $ map (cellswidth . rowToBudgetCells) items ++ [cellswidth $ rowToBudgetCells tr]
 
     -- split a BudgetCell into BudgetDisplayCell's (one per commodity when applicable)
diff --git a/hledger-lib/Hledger/Reports/ReportOptions.hs b/hledger-lib/Hledger/Reports/ReportOptions.hs
index d068a187b..24c5325c1 100644
--- a/hledger-lib/Hledger/Reports/ReportOptions.hs
+++ b/hledger-lib/Hledger/Reports/ReportOptions.hs
@@ -464,7 +464,7 @@ valuationTypeFromRawOpts rawopts = case (balancecalcopt rawopts, directcost, dir
     (CalcGain,        NoCost, Nothing       ) -> (directcost, Just $ AtEnd Nothing)  -- If no valuation requested for gain, use AtEnd
     (_,               _,      _             ) -> (directcost, directval)             -- Otherwise, use requested valuation
   where
-    directcost = if any (== Cost) (map fst valuationopts) then Cost else NoCost
+    directcost = if Cost `elem` map fst valuationopts then Cost else NoCost
     directval  = lastMay $ mapMaybe snd valuationopts
 
     valuationopts = collectopts valuationfromrawopt rawopts
@@ -551,9 +551,9 @@ mixedAmountApplyValuationAfterSumFromOptsWith :: ReportOpts -> Journal -> PriceO
 mixedAmountApplyValuationAfterSumFromOptsWith ropts j priceoracle =
     case valuationAfterSum ropts of
         Just mc -> case balancecalc_ ropts of
-            CalcGain -> \span  -> gain mc span
-            _        -> \span  -> valuation mc span . costing
-        Nothing      -> \_span -> id
+            CalcGain -> gain mc
+            _        -> \span -> valuation mc span . costing
+        Nothing      -> const id
   where
     valuation mc span = mixedAmountValueAtDate priceoracle styles mc (maybe err (addDays (-1)) $ spanEnd span)
     gain mc span = mixedAmountGainAtDate priceoracle styles mc (maybe err (addDays (-1)) $ spanEnd span)
diff --git a/hledger/Hledger/Cli/Commands/Balance.hs b/hledger/Hledger/Cli/Commands/Balance.hs
index 22df3fb67..120473c9c 100644
--- a/hledger/Hledger/Cli/Commands/Balance.hs
+++ b/hledger/Hledger/Cli/Commands/Balance.hs
@@ -677,7 +677,7 @@ balanceReportAsTable opts@ReportOpts{average_, row_total_, balanceaccum_}
       | no_total_ opts = id
       | otherwise =
         let totalrows = multiBalanceRowAsTableText opts tr
-            rh = Tab.Group NoLine $ map Header (replicate (length totalrows) "")
+            rh = Tab.Group NoLine . replicate (length totalrows) $ Header ""
             ch = Header [] -- ignored
          in (flip (concatTables SingleLine) $ Table rh ch totalrows)
     maybetranspose | transpose_ opts = \(Table rh ch vals) -> Table ch rh (transpose vals)