diff --git a/cardano-testnet/cardano-testnet.cabal b/cardano-testnet/cardano-testnet.cabal
index cd00694abbc..8566ad8afdf 100644
--- a/cardano-testnet/cardano-testnet.cabal
+++ b/cardano-testnet/cardano-testnet.cabal
@@ -174,6 +174,7 @@ test-suite cardano-testnet-test
   type:                 exitcode-stdio-1.0
 
   build-depends:        aeson
+                      , aeson-pretty
                       , async
                       , base16-bytestring
                       , bytestring
@@ -196,7 +197,6 @@ test-suite cardano-testnet-test
                       , time
                       , transformers
                       , transformers-except
-                      , yaml
 
   ghc-options:          -threaded -rtsopts -with-rtsopts=-N -with-rtsopts=-T
 
diff --git a/cardano-testnet/test/cardano-testnet-test/Cardano/Testnet/Test/SubmitApi/Babbage/Transaction.hs b/cardano-testnet/test/cardano-testnet-test/Cardano/Testnet/Test/SubmitApi/Babbage/Transaction.hs
index 47204bdffad..95d3533a011 100644
--- a/cardano-testnet/test/cardano-testnet-test/Cardano/Testnet/Test/SubmitApi/Babbage/Transaction.hs
+++ b/cardano-testnet/test/cardano-testnet-test/Cardano/Testnet/Test/SubmitApi/Babbage/Transaction.hs
@@ -44,12 +44,12 @@ import           Testnet.Runtime
 
 import qualified Cardano.Api.Ledger as L
 import qualified Data.Aeson as Aeson
+import qualified Data.Aeson.Encode.Pretty as Aeson
 import qualified Data.Aeson.Lens as Aeson
 import qualified Data.ByteString as BS
 import qualified Data.ByteString.Base16 as Base16
 import qualified Data.ByteString.Lazy as LBS
 import qualified Data.List as List
-import qualified Data.Yaml as Yaml
 import qualified Hedgehog.Extras.Test.Golden as H
 import           Lens.Micro
 import           Testnet.SubmitApi
@@ -95,7 +95,8 @@ hprop_transaction = H.integrationRetryWorkspace 0 "submit-api-babbage-transactio
   txbodySignedFp <- H.note $ work </> "tx.body.signed"
   txbodySignedBinFp <- H.note $ work </> "tx.body.signed.bin"
   txFailedResponseFp <- H.note $ work </> "tx.failed.response"
-  txFailedResponseYamlFp <- H.note $ work </> "tx.failed.response.yaml"
+  txFailedResponseYamlFp <- H.note $ work </> "tx.failed.response.json"
+  txFailedResponseYamlGoldenFp <- H.note "test/cardano-testnet-test/files/golden/tx.failed.response.json.golden"
 
   void $ execCli' execConfig
     [ "babbage", "query", "utxo"
@@ -195,12 +196,9 @@ hprop_transaction = H.integrationRetryWorkspace 0 "submit-api-babbage-transactio
 
     v <- H.leftFailM $ H.evalIO $ Aeson.eitherDecodeFileStrict @Aeson.Value txFailedResponseFp
 
-    let opts = Yaml.defaultEncodeOptions
-
-    H.evalIO $ Yaml.encodeFileWith opts txFailedResponseYamlFp v
-
-    H.diffFileVsGoldenFile txFailedResponseYamlFp "test/cardano-testnet-test/files/golden/tx.failed.response.yaml.golden"
+    H.evalIO $ LBS.writeFile txFailedResponseYamlFp $ Aeson.encodePretty v
 
+    H.diffFileVsGoldenFile txFailedResponseYamlFp txFailedResponseYamlGoldenFp
 
 redactHashLbs :: LBS.ByteString -> LBS.ByteString
 redactHashLbs = id
diff --git a/cardano-testnet/test/cardano-testnet-test/files/golden/tx.failed.response.json.golden b/cardano-testnet/test/cardano-testnet-test/files/golden/tx.failed.response.json.golden
new file mode 100644
index 00000000000..8561163b649
--- /dev/null
+++ b/cardano-testnet/test/cardano-testnet-test/files/golden/tx.failed.response.json.golden
@@ -0,0 +1,29 @@
+{
+    "contents": {
+        "contents": {
+            "contents": {
+                "era": "ShelleyBasedEraBabbage",
+                "error": [
+                    {
+                        "contents": {
+                            "contents": "AlonzoInBabbageUtxoPredFailure (ValueNotConservedUTxO (MaryValue (Coin 0) (MultiAsset (fromList []))) (MaryValue (Coin 300000000000) (MultiAsset (fromList []))))",
+                            "tag": "UtxoFailure"
+                        },
+                        "tag": "UtxowFailure"
+                    },
+                    {
+                        "contents": {
+                            "contents": "AlonzoInBabbageUtxoPredFailure (BadInputsUTxO (fromList [TxIn (TxId {unTxId = SafeHash \"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\"}) (TxIx 0)]))",
+                            "tag": "UtxoFailure"
+                        },
+                        "tag": "UtxowFailure"
+                    }
+                ],
+                "kind": "ShelleyTxValidationError"
+            },
+            "tag": "TxValidationErrorInCardanoMode"
+        },
+        "tag": "TxCmdTxSubmitValidationError"
+    },
+    "tag": "TxSubmitFail"
+}
\ No newline at end of file
diff --git a/cardano-testnet/test/cardano-testnet-test/files/golden/tx.failed.response.yaml.golden b/cardano-testnet/test/cardano-testnet-test/files/golden/tx.failed.response.yaml.golden
deleted file mode 100644
index 6b37ef39bab..00000000000
--- a/cardano-testnet/test/cardano-testnet-test/files/golden/tx.failed.response.yaml.golden
+++ /dev/null
@@ -1,21 +0,0 @@
-contents:
-  contents:
-    contents:
-      era: ShelleyBasedEraBabbage
-      error:
-      - contents:
-          contents: AlonzoInBabbageUtxoPredFailure (ValueNotConservedUTxO (MaryValue
-            (Coin 0) (MultiAsset (fromList []))) (MaryValue (Coin 300000000000) (MultiAsset
-            (fromList []))))
-          tag: UtxoFailure
-        tag: UtxowFailure
-      - contents:
-          contents: AlonzoInBabbageUtxoPredFailure (BadInputsUTxO (fromList [TxIn
-            (TxId {unTxId = SafeHash "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"})
-            (TxIx 0)]))
-          tag: UtxoFailure
-        tag: UtxowFailure
-      kind: ShelleyTxValidationError
-    tag: TxValidationErrorInCardanoMode
-  tag: TxCmdTxSubmitValidationError
-tag: TxSubmitFail