diff --git a/rusk/src/bin/config/chain.rs b/rusk/src/bin/config/chain.rs
index 3e310dc9d6..beeddeea2e 100644
--- a/rusk/src/bin/config/chain.rs
+++ b/rusk/src/bin/config/chain.rs
@@ -37,6 +37,7 @@ pub(crate) struct ChainConfig {
     block_gas_limit: Option<u64>,
 
     #[serde(with = "humantime_serde")]
+    #[serde(default)]
     genesis_timestamp: Option<SystemTime>,
 }