diff --git a/hydra-cardano-api/hydra-cardano-api.cabal b/hydra-cardano-api/hydra-cardano-api.cabal
index 4ea8d2e0929..1d567e4abe5 100644
--- a/hydra-cardano-api/hydra-cardano-api.cabal
+++ b/hydra-cardano-api/hydra-cardano-api.cabal
@@ -50,7 +50,6 @@ library
     Hydra.Cardano.Api.CtxUTxO
     Hydra.Cardano.Api.ExecutionUnits
     Hydra.Cardano.Api.Hash
-    Hydra.Cardano.Api.KeyWitness
     Hydra.Cardano.Api.Network
     Hydra.Cardano.Api.NetworkId
     Hydra.Cardano.Api.PlutusScript
diff --git a/hydra-cardano-api/src/Hydra/Cardano/Api.hs b/hydra-cardano-api/src/Hydra/Cardano/Api.hs
index 3311853452b..f2f3d32e8de 100644
--- a/hydra-cardano-api/src/Hydra/Cardano/Api.hs
+++ b/hydra-cardano-api/src/Hydra/Cardano/Api.hs
@@ -130,7 +130,6 @@ import Hydra.Cardano.Api.CtxTx as Extras
 import Hydra.Cardano.Api.CtxUTxO as Extras
 import Hydra.Cardano.Api.ExecutionUnits as Extras
 import Hydra.Cardano.Api.Hash as Extras
-import Hydra.Cardano.Api.KeyWitness as Extras
 import Hydra.Cardano.Api.NetworkId ()
 import Hydra.Cardano.Api.PlutusScript as Extras
 import Hydra.Cardano.Api.PolicyId as Extras
diff --git a/hydra-cardano-api/src/Hydra/Cardano/Api/KeyWitness.hs b/hydra-cardano-api/src/Hydra/Cardano/Api/KeyWitness.hs
deleted file mode 100644
index f97b96a7b10..00000000000
--- a/hydra-cardano-api/src/Hydra/Cardano/Api/KeyWitness.hs
+++ /dev/null
@@ -1,74 +0,0 @@
-module Hydra.Cardano.Api.KeyWitness where
-
-import Hydra.Cardano.Api.Prelude
-
-import Cardano.Ledger.Alonzo.TxWits qualified as Ledger
-import Cardano.Ledger.Era qualified as Ledger
-import Cardano.Ledger.Keys qualified as Ledger
-import Data.Set qualified as Set
-
--- * Extras
-
--- | Construct a 'KeyWitness' from a transaction id and credentials.
-signWith ::
-  forall era.
-  IsShelleyBasedEra era =>
-  TxId ->
-  SigningKey PaymentKey ->
-  KeyWitness era
-signWith (TxId h) signingKey@(PaymentSigningKey sk) =
-  let (PaymentVerificationKey vk) = getVerificationKey signingKey
-   in ShelleyKeyWitness (shelleyBasedEra @era) $
-        Ledger.WitVKey
-          (Ledger.asWitness vk)
-          (Ledger.signedDSIGN @StandardCrypto sk h)
-
--- * Type Conversions
-
--- | Convert a 'List' of cardano-api's 'KeyWitness' into a 'Set' of
--- cardano-ledger's 'WitVKey'.
---
--- NOTE: 'KeyWitness' is a bigger type than 'WitVKey' witness, this function
--- does not only the type conversion but also the selection of the right
--- underlying constructors. That means the size of the resulting set may be
--- smaller than the size of the list (but never bigger).
-toLedgerKeyWitness ::
-  [KeyWitness era] ->
-  Set (Ledger.WitVKey 'Ledger.Witness StandardCrypto)
-toLedgerKeyWitness vkWits =
-  Set.fromList [w | ShelleyKeyWitness _ w <- vkWits]
-
--- | Convert a 'List' of cardano-api's 'KeyWitness' into a 'Set' of
--- cardano-ledger's 'BootstrapWitness'.
---
--- NOTE: See note on 'toLedgerKeyWitness'.
-toLedgerBootstrapWitness ::
-  [KeyWitness era] ->
-  Set (Ledger.BootstrapWitness StandardCrypto)
-toLedgerBootstrapWitness vkWits =
-  Set.fromList [w | ShelleyBootstrapWitness _ w <- vkWits]
-
--- | Convert a cardano-ledger's 'TxWitness' object into a list of cardano-api's
--- 'KeyWitness'.
---
--- NOTE: this only concerns key and bootstrap witnesses. Scripts and auxiliary
--- data are obviously not part of the resulting list.
-fromLedgerTxWitness ::
-  forall era.
-  ( IsShelleyBasedEra era
-  , UsesStandardCrypto era
-  , Ledger.Era (ShelleyLedgerEra era)
-  ) =>
-  Ledger.AlonzoTxWits (ShelleyLedgerEra era) ->
-  [KeyWitness era]
-fromLedgerTxWitness wits =
-  mconcat
-    [ Set.foldr
-        ((:) . ShelleyKeyWitness shelleyBasedEra)
-        []
-        (Ledger.txwitsVKey' wits)
-    , Set.foldr
-        ((:) . ShelleyBootstrapWitness shelleyBasedEra)
-        []
-        (Ledger.txwitsBoot' wits)
-    ]