diff --git a/bolt-sidecar/src/config/mod.rs b/bolt-sidecar/src/config/mod.rs
index c3b1bfdd..ed59ce13 100644
--- a/bolt-sidecar/src/config/mod.rs
+++ b/bolt-sidecar/src/config/mod.rs
@@ -78,7 +78,7 @@ pub struct Opts {
     pub fee_recipient: Address,
     /// Secret BLS key to sign fallback payloads with. This can be any key. You can generate one
     /// with the `bolt` CLI tool, using `bolt generate bls`.
-    #[clap(long, env = "BOLT_SIDECAR_BUILDER_PRIVATE_KEY")]
+    #[clap(long, env = "BOLT_SIDECAR_BUILDER_PRIVATE_KEY", default_value_t = BlsSecretKeyWrapper::random())]
     pub builder_private_key: BlsSecretKeyWrapper,
     /// Secret ECDSA key used to sign commitment messages on behalf of your validators.
     /// This MUST be set to the private key of your operator address registered in a restaking protocol.
diff --git a/testnets/holesky/presets/sidecar-delegations-preset.env.example b/testnets/holesky/presets/sidecar-delegations-preset.env.example
index 79720546..9943e0af 100644
--- a/testnets/holesky/presets/sidecar-delegations-preset.env.example
+++ b/testnets/holesky/presets/sidecar-delegations-preset.env.example
@@ -25,9 +25,6 @@ BOLT_SIDECAR_FEE_RECIPIENT=
 # Secret ECDSA key used to sign commitment messages on behalf of your validators.
 # This MUST be set to the private key of your operator address registered in a restaking protocol.
 BOLT_SIDECAR_COMMITMENT_PRIVATE_KEY=
-# Secret BLS key to sign fallback payloads with. This can be any key. You can generate one
-# with the `bolt` CLI tool, using `bolt generate bls`.
-BOLT_SIDECAR_BUILDER_PRIVATE_KEY=
 
 # Commitments limits
 # Max number of commitments to accept per block