diff --git a/contiguous.cabal b/contiguous.cabal
--- a/contiguous.cabal
+++ b/contiguous.cabal
@@ -1,6 +1,6 @@
 cabal-version: 2.0
 name: contiguous
-version: 0.6.3.0
+version: 0.6.4.0
 homepage: https://github.com/andrewthad/contiguous
 bug-reports: https://github.com/andrewthad/contiguous/issues
 author: Andrew Martin
@@ -30,10 +30,10 @@
   hs-source-dirs: src
   build-depends:
       base >=4.14 && <5
-    , primitive >= 0.7.2 && < 0.8
-    , primitive-unlifted >= 0.1.3.1 && < 0.2
+    , primitive >= 0.7.2 && < 0.10
+    , primitive-unlifted >= 2.1
     , deepseq >= 1.4
-    , run-st >= 0.1.1
+    , run-st >= 0.1.3.2
   default-language: Haskell2010
   ghc-options: -O2 -Wall
 
diff --git a/src/Data/Primitive/Contiguous.hs b/src/Data/Primitive/Contiguous.hs
--- a/src/Data/Primitive/Contiguous.hs
+++ b/src/Data/Primitive/Contiguous.hs
@@ -37,6 +37,8 @@
   , doubleton
   , tripleton
   , quadrupleton
+  , quintupleton
+  , sextupleton
   , replicate
   , replicateMut
   , generate
@@ -45,6 +47,13 @@
   , iterateN
   , iterateMutableN
   , write
+    -- ** Fixed Length
+  , construct1
+  , construct2
+  , construct3
+  , construct4
+  , construct5
+  , construct6
     -- ** Running
   , run
     -- ** Monadic initialisation
@@ -246,13 +255,14 @@
 import Control.Monad.Primitive
 import Data.Primitive hiding (fromList,fromListN)
 import Data.Primitive.Unlifted.Array
-import Prelude hiding (map,all,any,foldr,foldMap,traverse,read,filter,replicate,null,reverse,foldl,foldr,zip,zipWith,scanl,(<$),elem,maximum,minimum,mapM,mapM_,sequence,sequence_)
+import Prelude hiding (Foldable(..),map,all,any,traverse,read,filter,replicate,reverse,zip,zipWith,scanl,(<$),mapM,mapM_,sequence,sequence_)
 
 import Control.Applicative (liftA2)
 import Control.Monad (when)
 import Control.Monad.ST (runST,ST)
 import Data.Bits (xor)
 import Data.Coerce (coerce)
+import Data.Foldable (length)
 import Data.Primitive.Contiguous.Class (Contiguous(..), ContiguousU(..), Slice, MutableSlice, Always)
 import Data.Semigroup (First(..))
 import Data.Word (Word8)
@@ -262,7 +272,36 @@
 import qualified Control.Applicative as A
 import qualified Prelude
 
+construct1 :: (Contiguous arr, Element arr a)
+  => a -> arr a
+{-# inline construct1 #-}
+construct1 = singleton
 
+construct2 :: (Contiguous arr, Element arr a)
+  => a -> a -> arr a
+{-# inline construct2 #-}
+construct2 = doubleton
+
+construct3 :: (Contiguous arr, Element arr a)
+  => a -> a -> a -> arr a
+{-# inline construct3 #-}
+construct3 = tripleton
+
+construct4 :: (Contiguous arr, Element arr a)
+  => a -> a -> a -> a -> arr a
+{-# inline construct4 #-}
+construct4 = quadrupleton
+
+construct5 :: (Contiguous arr, Element arr a)
+  => a -> a -> a -> a -> a -> arr a
+{-# inline construct5 #-}
+construct5 = quintupleton
+
+construct6 :: (Contiguous arr, Element arr a)
+  => a -> a -> a -> a -> a -> a -> arr a
+{-# inline construct6 #-}
+construct6 = sextupleton
+
 -- | Append two arrays.
 append :: (Contiguous arr, Element arr a) => arr a -> arr a -> arr a
 append !a !b = run $ do
@@ -1086,6 +1125,7 @@
   => Int
   -> (Int -> m a)
   -> m (arr a)
+{-# inline generateM #-}
 generateM !sz f =
   let go !ix = if ix < sz
         then liftA2
diff --git a/src/Data/Primitive/Contiguous/Class.hs b/src/Data/Primitive/Contiguous/Class.hs
--- a/src/Data/Primitive/Contiguous/Class.hs
+++ b/src/Data/Primitive/Contiguous/Class.hs
@@ -5,10 +5,12 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE MagicHash #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE TypeFamilyDependencies #-}
+{-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE UnboxedTuples #-}
 {-# LANGUAGE UnliftedNewtypes #-}
 
@@ -42,8 +44,13 @@
 import GHC.Exts (SmallMutableArray#,MutableArray#,MutableArrayArray#)
 import GHC.Exts (SmallArray#,Array#)
 import GHC.Exts (TYPE)
+import Data.Primitive.Unlifted.Array (MutableUnliftedArray,UnliftedArray)
+import Data.Primitive.Unlifted.Array (MutableUnliftedArray_(MutableUnliftedArray),UnliftedArray_(UnliftedArray))
+import Data.Primitive.Unlifted.Array.Primops (MutableUnliftedArray#(MutableUnliftedArray#),UnliftedArray#(UnliftedArray#))
 
 import qualified Control.DeepSeq as DS
+import qualified Data.Primitive.Unlifted.Class as Class
+import qualified GHC.Exts as Exts
 
 -- In GHC 9.2 the UnliftedRep constructor of RuntimeRep was removed
 -- and replaced with a type synonym
@@ -128,6 +135,10 @@
   tripleton :: Element arr a => a -> a -> a -> arr a
   -- | Create a quadrupleton array.
   quadrupleton :: Element arr a => a -> a -> a -> a -> arr a
+  -- | Create a quintupleton array.
+  quintupleton :: Element arr a => a -> a -> a -> a -> a -> arr a
+  -- | Create a sextupleton array.
+  sextupleton :: Element arr a => a -> a -> a -> a -> a -> a -> arr a
 
   ------ Access and Update ------
   -- | Index into an array at the given index.
@@ -388,7 +399,7 @@
   run :: (forall s. ST s (arr a)) -> arr a
 
 -- | The 'ContiguousU' typeclass is an extension of the 'Contiguous' typeclass,
--- but includes operations that make sense only on uncliced contiguous structures.
+-- but includes operations that make sense only on unsliced contiguous structures.
 --
 -- @since 0.6.0
 class (Contiguous arr) => ContiguousU arr where
@@ -453,6 +464,10 @@
   tripleton a b c = Slice{offset=0,length=3,base=unlift $ tripleton a b c}
   {-# INLINE quadrupleton #-}
   quadrupleton a b c d = Slice{offset=0,length=4,base=unlift $ quadrupleton a b c d}
+  {-# INLINE quintupleton #-}
+  quintupleton a b c d e = Slice{offset=0,length=5,base=unlift $ quintupleton a b c d e}
+  {-# INLINE sextupleton #-}
+  sextupleton a b c d e f = Slice{offset=0,length=6,base=unlift $ sextupleton a b c d e f}
 
   ------ Access and Update ------
   {-# INLINE index #-}
@@ -622,30 +637,43 @@
   equalsMut = (==)
   {-# INLINE singleton #-}
   singleton a = runST $ do
-    marr <- newSmallArray 1 errorThunk
-    writeSmallArray marr 0 a
+    marr <- newSmallArray 1 a
     unsafeFreezeSmallArray marr
   {-# INLINE doubleton #-}
   doubleton a b = runST $ do
-    m <- newSmallArray 2 errorThunk
-    writeSmallArray m 0 a
+    m <- newSmallArray 2 a
     writeSmallArray m 1 b
     unsafeFreezeSmallArray m
   {-# INLINE tripleton #-}
   tripleton a b c = runST $ do
-    m <- newSmallArray 3 errorThunk
-    writeSmallArray m 0 a
+    m <- newSmallArray 3 a
     writeSmallArray m 1 b
     writeSmallArray m 2 c
     unsafeFreezeSmallArray m
   {-# INLINE quadrupleton #-}
   quadrupleton a b c d = runST $ do
-    m <- newSmallArray 4 errorThunk
-    writeSmallArray m 0 a
+    m <- newSmallArray 4 a
     writeSmallArray m 1 b
     writeSmallArray m 2 c
     writeSmallArray m 3 d
     unsafeFreezeSmallArray m
+  {-# INLINE quintupleton #-}
+  quintupleton a b c d e = runST $ do
+    m <- newSmallArray 5 a
+    writeSmallArray m 1 b
+    writeSmallArray m 2 c
+    writeSmallArray m 3 d
+    writeSmallArray m 4 e
+    unsafeFreezeSmallArray m
+  {-# INLINE sextupleton #-}
+  sextupleton a b c d e f = runST $ do
+    m <- newSmallArray 6 a
+    writeSmallArray m 1 b
+    writeSmallArray m 2 c
+    writeSmallArray m 3 d
+    writeSmallArray m 4 e
+    writeSmallArray m 5 f
+    unsafeFreezeSmallArray m
   {-# INLINE rnf #-}
   rnf !ary =
     let !sz = sizeofSmallArray ary
@@ -768,6 +796,25 @@
     writePrimArray m 2 c
     writePrimArray m 3 d
     unsafeFreezePrimArray m
+  {-# INLINE quintupleton #-}
+  quintupleton a b c d e = runPrimArrayST $ do
+    m <- newPrimArray 5
+    writePrimArray m 0 a
+    writePrimArray m 1 b
+    writePrimArray m 2 c
+    writePrimArray m 3 d
+    writePrimArray m 4 e
+    unsafeFreezePrimArray m
+  {-# INLINE sextupleton #-}
+  sextupleton a b c d e f = runPrimArrayST $ do
+    m <- newPrimArray 6
+    writePrimArray m 0 a
+    writePrimArray m 1 b
+    writePrimArray m 2 c
+    writePrimArray m 3 d
+    writePrimArray m 4 e
+    writePrimArray m 5 f
+    unsafeFreezePrimArray m
   {-# INLINE insertAt #-}
   insertAt src i x = runPrimArrayST $ do
     dst <- new (size src + 1)
@@ -883,6 +930,23 @@
     writeArray m 2 c
     writeArray m 3 d
     unsafeFreezeArray m
+  {-# INLINE quintupleton #-}
+  quintupleton a b c d e = runArrayST $ do
+    m <- newArray 5 a
+    writeArray m 1 b
+    writeArray m 2 c
+    writeArray m 3 d
+    writeArray m 4 e
+    unsafeFreezeArray m
+  {-# INLINE sextupleton #-}
+  sextupleton a b c d e f = runArrayST $ do
+    m <- newArray 6 a
+    writeArray m 1 b
+    writeArray m 2 c
+    writeArray m 3 d
+    writeArray m 4 e
+    writeArray m 5 f
+    unsafeFreezeArray m
   {-# INLINE run #-}
   run = runArrayST
 
@@ -900,12 +964,14 @@
   {-# INLINE liftMut #-}
   liftMut x = MutableArray x
 
+class (Class.Unlifted a ~ u, PrimUnlifted a) => PrimUnliftsInto (u :: TYPE ('Exts.BoxedRep 'Exts.Unlifted)) (a :: Type) where
+instance (Class.Unlifted a ~ u, PrimUnlifted a) => PrimUnliftsInto u a
 
-instance Contiguous UnliftedArray where
-  type Mutable UnliftedArray = MutableUnliftedArray
-  type Element UnliftedArray = PrimUnlifted
-  type Sliced UnliftedArray = Slice UnliftedArray
-  type MutableSliced UnliftedArray = MutableSlice UnliftedArray
+instance Contiguous (UnliftedArray_ unlifted_a) where
+  type Mutable (UnliftedArray_ unlifted_a) = MutableUnliftedArray_ unlifted_a
+  type Element (UnliftedArray_ unlifted_a) = PrimUnliftsInto unlifted_a
+  type Sliced (UnliftedArray_ unlifted_a) = Slice (UnliftedArray_ unlifted_a)
+  type MutableSliced (UnliftedArray_ unlifted_a) = MutableSlice (UnliftedArray_ unlifted_a)
   {-# INLINE empty #-}
   empty = emptyUnliftedArray
   {-# INLINE new #-}
@@ -953,7 +1019,7 @@
   {-# INLINE equals #-}
   equals = (==)
   {-# INLINE null #-}
-  null (UnliftedArray a) = case sizeofArrayArray# a of
+  null (UnliftedArray (UnliftedArray# a)) = case Exts.sizeofArray# a of
     0# -> True
     _ -> False
   {-# INLINE equalsMut #-}
@@ -987,21 +1053,41 @@
     writeUnliftedArray m 2 c
     writeUnliftedArray m 3 d
     unsafeFreezeUnliftedArray m
+  {-# INLINE quintupleton #-}
+  quintupleton a b c d e = runUnliftedArrayST $ do
+    m <- newUnliftedArray 5 a
+    writeUnliftedArray m 1 b
+    writeUnliftedArray m 2 c
+    writeUnliftedArray m 3 d
+    writeUnliftedArray m 4 e
+    unsafeFreezeUnliftedArray m
+  {-# INLINE sextupleton #-}
+  sextupleton a b c d e f = runUnliftedArrayST $ do
+    m <- newUnliftedArray 6 a
+    writeUnliftedArray m 1 b
+    writeUnliftedArray m 2 c
+    writeUnliftedArray m 3 d
+    writeUnliftedArray m 4 e
+    writeUnliftedArray m 5 f
+    unsafeFreezeUnliftedArray m
   {-# INLINE run #-}
   run = runUnliftedArrayST
 
-newtype UnliftedArray# a = UnliftedArray# ArrayArray#
-newtype MutableUnliftedArray# s a = MutableUnliftedArray# (MutableArrayArray# s)
-instance ContiguousU UnliftedArray where
-  type Unlifted UnliftedArray = UnliftedArray#
-  type UnliftedMut UnliftedArray = MutableUnliftedArray#
+newtype UnliftedArray## (u :: TYPE UnliftedRep) (a :: Type) =
+  UnliftedArray## (Exts.Array# u)
+newtype MutableUnliftedArray## (u :: TYPE UnliftedRep) s (a :: Type) =
+  MutableUnliftedArray## (Exts.MutableArray# s u)
+
+instance ContiguousU (UnliftedArray_ unlifted_a) where
+  type Unlifted (UnliftedArray_ unlifted_a) = UnliftedArray## unlifted_a
+  type UnliftedMut (UnliftedArray_ unlifted_a) = MutableUnliftedArray## unlifted_a
   {-# INLINE resize #-}
   resize = resizeUnliftedArray
   {-# INLINE unlift #-}
-  unlift (UnliftedArray x) = (UnliftedArray# x)
+  unlift (UnliftedArray (UnliftedArray# x)) = UnliftedArray## x
   {-# INLINE unliftMut #-}
-  unliftMut (MutableUnliftedArray x) = (MutableUnliftedArray# x)
+  unliftMut (MutableUnliftedArray (MutableUnliftedArray# x)) = MutableUnliftedArray## x
   {-# INLINE lift #-}
-  lift (UnliftedArray# x) = UnliftedArray x
+  lift (UnliftedArray## x) = UnliftedArray (UnliftedArray# x)
   {-# INLINE liftMut #-}
-  liftMut (MutableUnliftedArray# x) = MutableUnliftedArray x
+  liftMut (MutableUnliftedArray## x) = MutableUnliftedArray (MutableUnliftedArray# x)