diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Revision history for json-syntax
 
+## 0.2.2.0 -- 2022-07-15
+
+* Build with GHC 9.2.3.
+* Test suite now requires aeson >= 2.0 instead of < 2.0.
+
 ## 0.2.1.0 -- 2022-03-01
 
 * Support Jackson's SMILE format as an encode target.
diff --git a/json-syntax.cabal b/json-syntax.cabal
--- a/json-syntax.cabal
+++ b/json-syntax.cabal
@@ -1,6 +1,6 @@
 cabal-version: 2.2
 name: json-syntax
-version: 0.2.1.0
+version: 0.2.2.0
 synopsis: High-performance JSON parser and encoder
 description:
   This library parses JSON into a @Value@ type that is consistent with the
@@ -36,14 +36,15 @@
     , bytebuild >=0.3.10 && <0.4
     , byteslice >=0.1.3 && <0.3
     , bytesmith >=0.3.8 && <0.4
-    , bytestring >=0.10.8 && <0.11
-    , integer-gmp >=1.0 && <1.1
+    , bytestring >=0.10.8 && <0.12
+    , integer-gmp >=1.0 && <1.2
     , natural-arithmetic >=0.1.2 && <0.2
     , contiguous >=0.6 && <0.7
     , primitive >=0.7 && <0.8
     , run-st >=0.1.1 && <0.2
-    , scientific-notation >=0.1.2 && <0.2
+    , scientific-notation >=0.1.5 && <0.2
     , text-short >=0.1.3 && <0.2
+    , word-compat >=0.0.3
     , zigzag >=0.0.1
   hs-source-dirs: src
   default-language: Haskell2010
@@ -59,12 +60,13 @@
   ghc-options: -Wall -O2
   build-depends:
     , QuickCheck >=2.14.2
-    , aeson <2.0
+    , aeson >=2.0.2
     , array-chunks
     , base >=4.12.0.0 && <5
     , bytebuild
     , byteslice >=0.1.3
     , bytestring
+    , containers
     , json-syntax
     , neat-interpolation >=0.3.2
     , primitive
@@ -76,7 +78,6 @@
     , tasty-quickcheck >=0.10.1.2 && <0.11
     , text >=1.2
     , text-short
-    , unordered-containers
     , vector
 
 benchmark bench
diff --git a/src/Json.hs b/src/Json.hs
--- a/src/Json.hs
+++ b/src/Json.hs
@@ -53,7 +53,7 @@
 import Data.Primitive (ByteArray,MutableByteArray,SmallArray)
 import Data.Text.Short (ShortText)
 import GHC.Exts (Char(C#),Int(I#),gtWord#,ltWord#,word2Int#,chr#)
-import GHC.Word (Word8(W8#),Word16(W16#))
+import GHC.Word (Word8,Word16)
 
 import qualified Prelude
 import qualified Data.Builder.ST as B
@@ -67,6 +67,7 @@
 import qualified Data.Bytes.Parser.Latin as Latin
 import qualified Data.ByteString.Short.Internal as BSS
 import qualified Data.Bytes.Parser.Unsafe as Unsafe
+import qualified GHC.Word.Compat
 
 -- | The JSON syntax tree described by the ABNF in RFC 7159. Notable
 -- design decisions include:
@@ -342,7 +343,7 @@
             let end = pos - 1
             let maxLen = end - start
             copyAndEscape wrap maxLen
-      W8# w -> go (canMemcpy .&. I# (ltWord# w 128##) .&. I# (gtWord# w 31##))
+      GHC.Word.Compat.W8# w -> go (canMemcpy .&. I# (ltWord# w 128##) .&. I# (gtWord# w 31##))
 
 copyAndEscape :: (ShortText -> a) -> Int -> Parser SyntaxException s a
 {-# inline copyAndEscape #-}
@@ -422,7 +423,7 @@
 
 -- Precondition: Not in the range [U+D800 .. U+DFFF]
 w16ToChar :: Word16 -> Char
-w16ToChar (W16# w) = C# (chr# (word2Int# w))
+w16ToChar (GHC.Word.Compat.W16# w) = C# (chr# (word2Int# w))
 
 -- | Infix pattern synonym for 'Member'.
 pattern (:->) :: ShortText -> Value -> Member
diff --git a/src/Json/Smile.hs b/src/Json/Smile.hs
--- a/src/Json/Smile.hs
+++ b/src/Json/Smile.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE BangPatterns #-}
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE GADTs #-}
 {-# LANGUAGE MagicHash #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE ScopedTypeVariables #-}
diff --git a/test/Main.hs b/test/Main.hs
--- a/test/Main.hs
+++ b/test/Main.hs
@@ -22,7 +22,8 @@
 import qualified Data.Bytes.Text.Ascii as Ascii
 import qualified Data.Bytes.Text.Latin1 as Latin1
 import qualified Data.ByteString as BS
-import qualified Data.HashMap.Strict as HM
+import qualified Data.Aeson.Key as Key
+import qualified Data.Aeson.KeyMap as M
 import qualified Data.Number.Scientific as SCI
 import qualified Data.Text.Short as TS
 import qualified GHC.Exts as Exts
@@ -227,8 +228,8 @@
   J.String t -> AE.String (TS.toText t)
   J.Number n -> AE.Number (toBadSci n)
   J.Object mbrs -> AE.Object $ foldr
-    (\(J.Member key val) hm -> HM.insert (TS.toText key) (toAesonValue val) hm)
-    HM.empty mbrs
+    (\(J.Member key val) hm -> M.insert (Key.fromShortText key) (toAesonValue val) hm)
+    M.empty mbrs
   J.Array vals -> AE.Array $ Exts.fromList $ foldr
     (\x xs -> toAesonValue x : xs) [] vals