diff --git a/contracts/prebuilts/token/TokenERC1155.sol b/contracts/prebuilts/token/TokenERC1155.sol
index 8856ebf64..89288fbd8 100644
--- a/contracts/prebuilts/token/TokenERC1155.sol
+++ b/contracts/prebuilts/token/TokenERC1155.sol
@@ -80,7 +80,7 @@ contract TokenERC1155 is
     /// @dev Only TRANSFER_ROLE holders can have tokens transferred from or to them, during restricted transfers.
     bytes32 private constant TRANSFER_ROLE = keccak256("TRANSFER_ROLE");
     /// @dev Only MINTER_ROLE holders can sign off on `MintRequest`s.
-    bytes32 private constant MINTER_ROLE = keccak256("MINTER_ROLE");
+    bytes32 internal constant MINTER_ROLE = keccak256("MINTER_ROLE");
     /// @dev Only METADATA_ROLE holders can update NFT metadata.
     bytes32 private constant METADATA_ROLE = keccak256("METADATA_ROLE");
 
@@ -143,7 +143,7 @@ contract TokenERC1155 is
         uint128 _royaltyBps,
         uint128 _platformFeeBps,
         address _platformFeeRecipient
-    ) external initializer {
+    ) public virtual initializer {
         // Initialize inherited contracts, most base-like -> most derived.
         __ReentrancyGuard_init();
         __EIP712_init("TokenERC1155", "1");