diff --git a/eth-contracts/contracts/Aggregator.sol b/eth-contracts/contracts/Aggregator.sol
deleted file mode 100644
index f6fad23..0000000
--- a/eth-contracts/contracts/Aggregator.sol
+++ /dev/null
@@ -1,23 +0,0 @@
-//SPDX-License-Identifier: MIT
-pragma solidity >= 0.5.0 < 0.7.0;
-
-import "@openzeppelin/contracts/access/Ownable.sol";
-import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
-import "./DioneStaking.sol";
-
-interface IMediator {
-    function _receiveDataCallback(uint256 reqID, string memory data) external;
-}
-
-contract Aggregator is Ownable, ReentrancyGuard {
-  DioneStaking public dioneStaking;
-
-  constructor(DioneStaking _dioneStaking) public {
-      dioneStaking = _dioneStaking;
-  }
-
-  function collectData(uint256 reqID, string memory data, IMediator callbackAddress) public {
-    dioneStaking.mine(msg.sender);
-    callbackAddress._receiveDataCallback(reqID, data);
-  }
-}
diff --git a/eth-contracts/contracts/DioneOracle.sol b/eth-contracts/contracts/DioneOracle.sol
index 54027e1..4d1adb6 100644
--- a/eth-contracts/contracts/DioneOracle.sol
+++ b/eth-contracts/contracts/DioneOracle.sol
@@ -87,7 +87,7 @@ contract DioneOracle is Ownable {
     require(pendingRequests[_reqID] == requestHash, "Params do not match request ID");
     delete pendingRequests[_reqID];
     dioneStaking.mine(msg.sender);
-    (bool success, ) = _callbackAddress.call(abi.encodeWithSelector(_callbackMethodID, _reqID, _data));
+    (bool success, ) = _callbackAddress.call(abi.encodeWithSelector(_callbackMethodID, _reqID, _data)); // TODO: check on success call
     emit SubmittedOracleRequest(_requestParams, _callbackAddress, _callbackMethodID, _reqID, _requestDeadline, _data);
     return success;
   }
diff --git a/eth-contracts/contracts/Mediator.sol b/eth-contracts/contracts/Mediator.sol
deleted file mode 100644
index 75c9fee..0000000
--- a/eth-contracts/contracts/Mediator.sol
+++ /dev/null
@@ -1,29 +0,0 @@
-//SPDX-License-Identifier: MIT
-pragma solidity >= 0.5.0 < 0.7.0;
-
-import "./vendor/Ownable.sol";
-import "./OracleEmitter.sol";
-
-contract Mediator is Ownable {
-  event DataReceived(
-    uint256 reqID,
-    string data
-  );
-
-  OracleEmitter oracleEmitter;
-  address aggregator;
-
-  constructor(address _oracleEmitter, address _aggregator) public Ownable() {
-    oracleEmitter = OracleEmitter(_oracleEmitter);
-    aggregator = _aggregator;
-  }
-
-  function request(uint8 originChain, string memory requestType, string memory requestParams) public returns (uint256) {
-    return oracleEmitter.requestOracles(originChain, requestType, requestParams, address(this), bytes4(keccak256("_receiveDataCallback(uint256, string)")));
-  }
-
-  function _receiveDataCallback(uint256 reqID, string memory data) public {
-    require(msg.sender == aggregator);
-    emit DataReceived(reqID, data);
-  }
-}
diff --git a/eth-contracts/contracts/OracleEmitter.sol b/eth-contracts/contracts/OracleEmitter.sol
deleted file mode 100644
index 36ae5d6..0000000
--- a/eth-contracts/contracts/OracleEmitter.sol
+++ /dev/null
@@ -1,21 +0,0 @@
-// SPDX-License-Identifier: MIT
-pragma solidity >=0.4.21 <0.7.0;
-
-contract OracleEmitter {
-  uint256 requestCounter;
-
-  event NewOracleRequest(
-    uint8 originChain,
-    string requestType,
-    string requestParams,
-    address callbackAddress,
-    bytes4 callbackMethodID,
-    uint256 requestID
-  );
-
-  function requestOracles(uint8 originChain, string memory requestType, string memory requestParams, address callbackAddress, bytes4 callbackMethodID) public returns (uint256) {
-    requestCounter++;
-    emit NewOracleRequest(originChain, requestType, requestParams, callbackAddress, callbackMethodID, requestCounter);
-    return requestCounter;
-  }
-}