diff --git a/solutions/solutions.cabal b/solutions/solutions.cabal
index d37cfce..1874819 100644
--- a/solutions/solutions.cabal
+++ b/solutions/solutions.cabal
@@ -1003,7 +1003,7 @@ executable sln_2023_02
 executable sln_2023_03
   import:              day
   main-is:             2023/03.hs
-  build-depends:       containers
+  build-depends:       array, containers
 
 executable sln_2023_04
   import:              day
@@ -1035,7 +1035,7 @@ executable sln_2023_09
 executable sln_2023_10
   import:              day
   main-is:             2023/10.hs
-  build-depends:       containers
+  build-depends:       array
 
 executable sln_2023_11
   import:              day
diff --git a/solutions/src/2022/23.hs b/solutions/src/2022/23.hs
index 018c83c..d24f785 100644
--- a/solutions/src/2022/23.hs
+++ b/solutions/src/2022/23.hs
@@ -22,16 +22,16 @@ Maintainer  : emertens@gmail.com
 20
 
 -}
-module Main where
+module Main (main) where
 
-import Data.Array.Unboxed (Ix(rangeSize), UArray, accumArray)
+import Data.Array.Unboxed (UArray, assocs, rangeSize, UArray, accumArray)
 import Data.List (foldl', tails)
 import Data.Map qualified as Map
 import Data.Maybe (fromMaybe)
 import Data.Set (Set)
 import Data.Set qualified as Set
 
-import Advent (arrIx, getInputMap)
+import Advent (arrIx, getInputArray)
 import Advent.Coord (Coord, above, below, boundingBox, left, neighbors, right)
 
 -- |
@@ -40,7 +40,8 @@ import Advent.Coord (Coord, above, below, boundingBox, left, neighbors, right)
 -- 1023
 main :: IO ()
 main =
- do elves <- Map.keysSet . Map.filter ('#'==) <$> getInputMap 2022 23
+ do input <- getInputArray 2022 23
+    let elves = Set.fromList [c | (c, '#') <- assocs input]
     let states = sim elves
 
     -- part 1
diff --git a/solutions/src/2023/03.hs b/solutions/src/2023/03.hs
index 68ad186..28914bf 100644
--- a/solutions/src/2023/03.hs
+++ b/solutions/src/2023/03.hs
@@ -27,12 +27,12 @@ Maintainer  : emertens@gmail.com
 -}
 module Main (main) where
 
-import Data.Map (Map)
-import Data.Map qualified as Map
-import Data.Char (isDigit)
-
-import Advent (getInputMap, ordNub)
+import Advent (getInputArray, ordNub, arrIx)
 import Advent.Coord (Coord, left, neighbors, right)
+import Data.Array.Unboxed (UArray, assocs)
+import Data.Char (isDigit)
+import Data.Map qualified as Map
+import Data.Maybe (fromMaybe)
 
 -- | Parse the input schematic and print answers to both parts.
 --
@@ -41,21 +41,21 @@ import Advent.Coord (Coord, left, neighbors, right)
 -- 81463996
 main :: IO ()
 main =
- do input <- getInputMap 2023 3
+ do input <- getInputArray 2023 3
     let numbers = extractNumbers input
     print (sum [partNo | (partNo, _:_) <- numbers])
     print (sum [a * b | [a, b] <- gearNumbers numbers])
 
 -- | Extract the numbers from the diagram and the parts adjacent to them.
-extractNumbers :: Map Coord Char -> [(Int, [(Coord, Char)])]
+extractNumbers :: UArray Coord Char -> [(Int, [(Coord, Char)])]
 extractNumbers input =
   [ (read digits, partsNear cs)
-  | (c, digit) <- Map.assocs input
+  | (c, digit) <- assocs input
   , isDigit digit, not (isDigit (lkp (left c))) -- left-boundary of number
   , let (cs, digits) = unzip (numbersAfter c)
   ]
   where
-    lkp i = Map.findWithDefault '.' i input
+    lkp = fromMaybe '.' . arrIx input
     numbersAfter start =
       [ (c, digit)
       | c <- iterate right start
diff --git a/solutions/src/2023/07.hs b/solutions/src/2023/07.hs
index 2096a70..9030388 100644
--- a/solutions/src/2023/07.hs
+++ b/solutions/src/2023/07.hs
@@ -28,12 +28,12 @@ module Main (main) where
 
 import Advent (format, counts)
 import Data.Foldable (toList)
-import Data.List (sortOn, sortBy, elemIndex, nub)
+import Data.List (sortOn, sortBy, elemIndex)
 import Data.Maybe (fromJust)
 import Data.Map (Map)
 import Data.Map qualified as Map
 
--- |
+-- | Parse the input hands and print the answers to both parts.
 --
 -- >>> :main
 -- 248422077
diff --git a/solutions/src/2023/10.hs b/solutions/src/2023/10.hs
index f4de090..d17adbc 100644
--- a/solutions/src/2023/10.hs
+++ b/solutions/src/2023/10.hs
@@ -60,11 +60,9 @@ L7JLJL-JLJLJL--JLJ.L
 -}
 module Main (main) where
 
-import Advent (getInputMap)
+import Advent (getInputArray, arrIx)
 import Advent.Coord (invert, invert', south, north, west, Coord(C))
-import Advent.Search (dfsOn)
-import Data.Map (Map)
-import Data.Map qualified as Map
+import Data.Array.Unboxed (UArray, (!), assocs)
 
 -- | Parse the input and print out answers to both parts.
 --
@@ -73,29 +71,30 @@ import Data.Map qualified as Map
 -- 541
 main :: IO ()
 main =
- do input <- getInputMap 2023 10
+ do input <- getInputArray 2023 10
     let (start, dir0) = pickStart input
         route = getLoop (map fst (iterate (step input) (start, dir0)))
         perimeter = length route
     print (perimeter `quot` 2)
     print (abs (polyareaRect route) - perimeter `quot` 2 + 1)
 
-pickStart :: Map Coord Char -> (Coord, Coord)
+pickStart :: UArray Coord Char -> (Coord, Coord)
 pickStart input = head
   [ (k, dir)
-  | (k, 'S') <- Map.assocs input
+  | (k, 'S') <- assocs input
   , (dir, ok) <- [(south, "L|J"), (north, "F|7"), (west,"7-J")]
-  , let next = Map.findWithDefault '.' (k + dir) input
+  , next <- arrIx input (k + dir)
   , next `elem` ok
   ]
 
 getLoop :: Eq a => [a] -> [a]
 getLoop (x:xs) = x : takeWhile (x /=) xs
+getLoop [] = error "getLoop: empty input"
 
-step :: Map Coord Char -> (Coord, Coord) -> (Coord, Coord)
+step :: UArray Coord Char -> (Coord, Coord) -> (Coord, Coord)
 step inp (here, dir) =
   let here' = here + dir in
-  (here', pipeEffect (inp Map.! here') dir)
+  (here', pipeEffect (inp ! here') dir)
 
 pipeEffect :: Char -> Coord -> Coord
 pipeEffect = \case