diff --git a/src/rollup/RollupCore.sol b/src/rollup/RollupCore.sol
index a62655ff..8378319d 100644
--- a/src/rollup/RollupCore.sol
+++ b/src/rollup/RollupCore.sol
@@ -49,6 +49,8 @@ abstract contract RollupCore is IRollupCore, PausableUpgradeable {
     address public stakeToken;
     uint256 public minimumAssertionPeriod;
 
+
+    // adding some lines
     mapping(address => bool) public isValidator;
 
     // Stakers become Zombies after losing a challenge