diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # Revision history for greskell
 
+## 2.0.3.5  -- 2026-05-25
+
+- Support aeson-2.3.
+
 ## 2.0.3.4  -- 2026-04-21
 
 - Bump dependency version bounds.
diff --git a/greskell.cabal b/greskell.cabal
--- a/greskell.cabal
+++ b/greskell.cabal
@@ -1,5 +1,5 @@
 name:                   greskell
-version:                2.0.3.4
+version:                2.0.3.5
 author:                 Toshio Ito <debug.ito@gmail.com>
 maintainer:             Toshio Ito <debug.ito@gmail.com>
 license:                BSD3
@@ -44,7 +44,7 @@
                         greskell-core ^>=1.0.0,
                         text ^>=1.2.3 || ^>=2.0.2 || ^>=2.1,
                         transformers ^>=0.5.6 || ^>=0.6.1,
-                        aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3,
+                        aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3 || ^>=2.3.0,
                         unordered-containers ^>=0.2.15,
                         semigroups ^>=0.20,
                         vector ^>=0.12.3 || ^>=0.13.0,
@@ -71,7 +71,7 @@
   build-tool-depends:   hspec-discover:hspec-discover
   build-depends:        base ^>=4.13.0 || ^>=4.14.0 || ^>=4.15.0 || ^>=4.16.0 || ^>=4.17.0 || ^>=4.18.0 || ^>=4.19.0 || ^>=4.20.0 || ^>=4.21.0 || ^>=4.22.0,
                         text ^>=1.2.3 || ^>=2.0.2 || ^>=2.1,
-                        aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3,
+                        aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3 || ^>=2.3.0,
                         unordered-containers ^>=0.2.15,
                         greskell,
                         greskell-core ^>=1.0.0,
@@ -105,7 +105,7 @@
   if flag(server-test)
     -- Explicitly remove dependency. See https://github.com/haskell/cabal/issues/1725
     build-depends:        base ^>=4.13.0 || ^>=4.14.0 || ^>=4.15.0 || ^>=4.16.0 || ^>=4.17.0 || ^>=4.18.0 || ^>=4.19.0 || ^>=4.20.0 || ^>=4.21.0 || ^>=4.22.0,
-                          aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3,
+                          aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3 || ^>=2.3.0,
                           hspec ^>=2.9.1 || ^>=2.10.6 || ^>=2.11.9,
                           text ^>=1.2.3 || ^>=2.0.2 || ^>=2.1,
                           unordered-containers ^>=0.2.15,
@@ -136,7 +136,7 @@
   other-modules:        ServerTest.Common
   if flag(server-behavior-test)
     build-depends:        base ^>=4.13.0 || ^>=4.14.0 || ^>=4.15.0 || ^>=4.16.0 || ^>=4.17.0 || ^>=4.18.0 || ^>=4.19.0 || ^>=4.20.0 || ^>=4.21.0 || ^>=4.22.0,
-                          aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3,
+                          aeson ^>=2.0.2 || ^>=2.1.0 || ^>=2.2.3 || ^>=2.3.0,
                           hspec ^>=2.9.1 || ^>=2.10.6 || ^>=2.11.9,
                           text ^>=1.2.3 || ^>=2.0.2 || ^>=2.1,
                           unordered-containers ^>=0.2.15,