diff --git a/cardano-testnet/cardano-testnet.cabal b/cardano-testnet/cardano-testnet.cabal
index a532f3276b7..e4473f12d67 100644
--- a/cardano-testnet/cardano-testnet.cabal
+++ b/cardano-testnet/cardano-testnet.cabal
@@ -56,6 +56,8 @@ library
                       , filepath
                       , hedgehog
                       , hedgehog-extras ^>= 0.4.7.0
+                      , microlens
+                      , lens-aeson
                       , mtl
                       , network
                       , network-mux
diff --git a/cardano-testnet/src/Testnet/Components/Configuration.hs b/cardano-testnet/src/Testnet/Components/Configuration.hs
index 93fbf638e74..812e26c319d 100644
--- a/cardano-testnet/src/Testnet/Components/Configuration.hs
+++ b/cardano-testnet/src/Testnet/Components/Configuration.hs
@@ -37,6 +37,9 @@ import qualified Hedgehog.Extras.Stock.Time as DTC
 import qualified Hedgehog.Extras.Test.Base as H
 import qualified Hedgehog.Extras.Test.File as H
 
+import qualified Data.Aeson.Lens as L
+import           Lens.Micro
+
 import           Testnet.Defaults
 import           Testnet.Filepath
 import           Testnet.Process.Run (execCli_)
@@ -102,20 +105,12 @@ createSPOGenesisAndFiles testnetOptions startTime (TmpAbsolutePath tempAbsPath')
   -- TODO: Remove this rewrite.
  -- 50 second epochs
  -- Epoch length should be "10 * k / f" where "k = securityParam, f = activeSlotsCoeff"
-  H.rewriteJsonFile createStakedInitialGenesisFile $ \o ->
-    o
-  -- J.rewriteObject
-  --     ( HM.insert "securityParam"          (toJSON @Int 5)    -- TODO: USE config p arameter
-  --     . HM.adjust
-  --         (J.rewriteObject
-  --             $ HM.adjust
-  --               (J.rewriteObject (HM.insert "major" (toJSON @Int 8)))
-  --               "protocolVersion"
-  --         )   "protocolParams"
-  --     . HM.insert "rho"                    (toJSON @Double 0.1)
-  --     . HM.insert "tau"                    (toJSON @Double 0.1)
-  --     . HM.insert "updateQuorum"           (toJSON @Int 2)
-  --     )
+  H.rewriteJsonFile createStakedInitialGenesisFile $ \o -> o
+    & L.key "securityParam" . L._Integer .~ 5
+    & L.key "rho" . L._Double  .~ 0.1
+    & L.key "tau" . L._Double  .~ 0.1
+    & L.key "updateQuorum" . L._Integer .~ 2
+    & L.key "protocolParams" . L.key "protocolVersion" . L.key "major" . L._Integer .~ 8
 
   execCli_
     [ "genesis", "create-staked"