diff --git a/.github/workflows/haskell-ci.yml b/.github/workflows/haskell-ci.yml
index e957050..909dd81 100644
--- a/.github/workflows/haskell-ci.yml
+++ b/.github/workflows/haskell-ci.yml
@@ -8,9 +8,9 @@
 #
 # For more information, see https://github.com/haskell-CI/haskell-ci
 #
-# version: 0.19.20260209
+# version: 0.19.20260331
 #
-# REGENDATA ("0.19.20260209",["github","--config=cabal.haskell-ci","tagged-json.cabal"])
+# REGENDATA ("0.19.20260331",["github","--config=cabal.haskell-ci","tagged-json.cabal"])
 #
 name: Haskell-CI
 on:
@@ -37,9 +37,9 @@ jobs:
     strategy:
       matrix:
         include:
-          - compiler: ghc-9.12.2
+          - compiler: ghc-9.12.4
             compilerKind: ghc
-            compilerVersion: 9.12.2
+            compilerVersion: 9.12.4
             setup-method: ghcup
             allow-failure: false
           - compiler: ghc-9.10.3
@@ -183,8 +183,6 @@ jobs:
           echo "packages: ${PKGDIR_tagged_json}" >> cabal.project
           echo "package tagged-json" >> cabal.project
           echo "    ghc-options: -Werror=missing-methods -Werror=missing-fields" >> cabal.project
-          if [ $((HCNUMVER >= 90400)) -ne 0 ] ; then echo "package tagged-json" >> cabal.project ; fi
-          if [ $((HCNUMVER >= 90400)) -ne 0 ] ; then echo "    ghc-options: -Werror=unused-packages" >> cabal.project ; fi
           echo "package tagged-json" >> cabal.project
           echo "    ghc-options: -Werror=incomplete-patterns -Werror=incomplete-uni-patterns" >> cabal.project
           cat >> cabal.project <<EOF
diff --git a/cabal.haskell-ci b/cabal.haskell-ci
index b17fdda..55dec8d 100644
--- a/cabal.haskell-ci
+++ b/cabal.haskell-ci
@@ -1,4 +1,5 @@
-branches:     main
-cabal-check:  False
-doctest:      False
-tests:        True
+branches: main
+cabal-check: False
+doctest: False
+error-unused-packages: False
+tests: True
diff --git a/src/Deriving/TaggedJson.hs b/src/Deriving/TaggedJson.hs
index e7e8475..bc50fd7 100644
--- a/src/Deriving/TaggedJson.hs
+++ b/src/Deriving/TaggedJson.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE CPP #-}
 
 module Deriving.TaggedJson (
   GTaggedJSON (..),
@@ -23,7 +24,6 @@ import Control.Applicative
 import Data.Aeson.Key qualified as Key
 import Data.Aeson.KeyMap qualified as KeyMap
 import Data.Aeson.Types hiding (genericParseJSON, genericToEncoding, genericToJSON)
-import Data.HashMap.Strict.InsOrd qualified as HMSI
 import Data.Kind
 import Data.List (intercalate)
 import Data.Maybe
@@ -37,6 +37,17 @@ import GHC.Generics
 import GHC.TypeLits
 import Optics hiding (to)
 
+-- This is due to a breaking change introduced in insert-ordered-containers-0.3.0
+-- More info are available here:
+--   https://github.com/biocad/openapi3/pull/119
+--   https://github.com/erikd/insert-ordered-containers/pull/8
+--
+#if MIN_VERSION_openapi3(3,2,5) && MIN_VERSION_insert_ordered_containers(0,3,0)
+import Data.HashMap.Strict.InsOrd.Compat qualified as HMSI
+#else
+import Data.HashMap.Strict.InsOrd qualified as HMSI
+#endif
+
 -- * Serialization options
 
 data TaggedOptions = TaggedOptions
diff --git a/tagged-json.cabal b/tagged-json.cabal
index 9996807..30df635 100644
--- a/tagged-json.cabal
+++ b/tagged-json.cabal
@@ -24,7 +24,7 @@ tested-with:
    || ==9.6.7
    || ==9.8.4
    || ==9.10.3
-   || ==9.12.2
+   || ==9.12.4
 
 source-repository head
   type:     git