diff --git a/ouroboros-consensus/ouroboros-consensus.cabal b/ouroboros-consensus/ouroboros-consensus.cabal
index ba15332b40..e06bb85047 100644
--- a/ouroboros-consensus/ouroboros-consensus.cabal
+++ b/ouroboros-consensus/ouroboros-consensus.cabal
@@ -464,6 +464,7 @@ library unstable-mock-block
     ouroboros-network-api,
     ouroboros-network-mock,
     serialise,
+    text,
     time,
     unstable-consensus-testlib,
 
diff --git a/ouroboros-consensus/src/unstable-mock-block/Ouroboros/Consensus/Mock/Ledger/Address.hs b/ouroboros-consensus/src/unstable-mock-block/Ouroboros/Consensus/Mock/Ledger/Address.hs
index 1f0f40b30c..b946df94a0 100644
--- a/ouroboros-consensus/src/unstable-mock-block/Ouroboros/Consensus/Mock/Ledger/Address.hs
+++ b/ouroboros-consensus/src/unstable-mock-block/Ouroboros/Consensus/Mock/Ledger/Address.hs
@@ -6,11 +6,13 @@ module Ouroboros.Consensus.Mock.Ledger.Address (
   , mkAddrDist
   ) where
 
+import           Cardano.Binary (FromCBOR (..), ToCBOR (..))
 import           Codec.Serialise (Serialise)
 import           Control.DeepSeq (NFData)
 import           Data.Map.Strict (Map)
 import qualified Data.Map.Strict as Map
 import           Data.String
+import           Data.Text (pack, unpack)
 import           NoThunks.Class (NoThunks)
 import           Ouroboros.Consensus.Node.ProtocolInfo
 import           Ouroboros.Consensus.NodeId (NodeId (..))
@@ -28,6 +30,12 @@ newtype Addr = Addr String
     , NoThunks
     )
 
+instance ToCBOR Addr where
+  toCBOR (Addr a) = toCBOR $ pack a
+
+instance FromCBOR Addr where
+  fromCBOR = Addr . unpack <$> fromCBOR
+
 instance Condense Addr where
   condense (Addr addr) = addr