diff --git a/posix-api.cabal b/posix-api.cabal
index 70095b6..1d1bbe0 100644
--- a/posix-api.cabal
+++ b/posix-api.cabal
@@ -82,13 +82,6 @@ flag assertions
   description: Extra run-time invariant checking
   default:     False
 
--- This only exists to help get this library to build on hackage.
--- Whenever hackage moves to GHC 9.4, remove this.
-flag unliftedarrayfunctions
-  manual:      True
-  description: Build and export functions using unlifted arrays
-  default:     True
-
 common build-settings
   default-language: Haskell2010
   ghc-options:      -Wall -Wunused-packages
@@ -126,15 +119,12 @@ library
     , base              >=4.16.3 && <5
     , byte-order        >=0.1.2  && <0.2
     , byteslice         >=0.2.10 && <0.3
-    , primitive         >=0.7    && <0.10
+    , primitive         >=0.9    && <0.10
     , primitive-addr    >=0.1    && <0.2
     , primitive-offset  >=0.2    && <0.3
     , run-st            >=0.1.1  && <0.2
     , text-short        >=0.1.5
 
-  if flag(unliftedarrayfunctions)
-    build-depends: primitive-unlifted >=2.1 && <2.2
-
   hs-source-dirs:     src
 
   if flag(assertions)
diff --git a/src-assertions/Assertion.hs b/src-assertions/Assertion.hs
index 8303667..b975b1a 100644
--- a/src-assertions/Assertion.hs
+++ b/src-assertions/Assertion.hs
@@ -13,24 +13,16 @@ import qualified GHC.Exts as Exts
 
 assertMutablePrimArrayPinned :: PM.MutablePrimArray s a -> PM.MutablePrimArray s a
 assertMutablePrimArrayPinned x =
-  if isMutablePrimArrayPinned x
+  if PM.isMutablePrimArrayPinned x
     then x
     else error "assertMutablePrimArrayPinned"
 
-assertMutableByteArrayPinned :: PM.MutablePrimArray s a -> PM.MutablePrimArray s a
+assertMutableByteArrayPinned :: PM.MutableByteArray s -> PM.MutableByteArray s
 assertMutableByteArrayPinned x =
-  if isMutableByteArrayPinned x
+  if PM.isMutableByteArrayPinned x
     then x
     else error "assertMutableByteArrayPinned"
 
-isMutablePrimArrayPinned :: PM.MutablePrimArray s a -> Bool
-{-# INLINE isMutablePrimArrayPinned #-}
-isMutablePrimArrayPinned (PM.MutablePrimArray marr#) = isTrue# (Exts.isMutableByteArrayPinned# marr#)
-
-isMutableByteArrayPinned :: PM.MutableByteArray s -> Bool
-{-# INLINE isMutableByteArrayPinned #-}
-isMutableByteArrayPinned (PM.MutableByteArray marr#) = isTrue# (Exts.isMutableByteArrayPinned# marr#)
-
 assertByteArrayPinned :: PM.ByteArray -> PM.ByteArray
 assertByteArrayPinned x =
   if PM.isByteArrayPinned x