diff --git a/contracts/market/MallBase.sol b/contracts/market/MallBase.sol
index 8b6f06c..8cf2267 100644
--- a/contracts/market/MallBase.sol
+++ b/contracts/market/MallBase.sol
@@ -3,7 +3,7 @@ pragma solidity 0.8.10;
 
 import "@openzeppelin/contracts/access/Ownable.sol";
 
-contract MallBase is Ownable {
+abstract contract MallBase is Ownable {
   address public executor;
   // Address to receive transaction fee
   address public feeToAddress;