Downgraded Solidity version on TWAP and added imports

contracts/oracles/SimpleSLPTWAP0Oracle.sol

@@ -1,15 +1,22 @@
 // SPDX-License-Identifier: AGPL-3.0-only
 // Using the same Copyleft License as in the original Repository
-pragma solidity 0.6.12;
+pragma solidity 0.6.8;
 pragma experimental ABIEncoderV2;
 import "../interfaces/IOracle.sol";
-import "@boringcrypto/boring-solidity/contracts/libraries/BoringMath.sol";
 import "@sushiswap/core/contracts/uniswapv2/interfaces/IUniswapV2Factory.sol";
-import "@sushiswap/core/contracts/uniswapv2/interfaces/IUniswapV2Pair.sol";
+import '@keydonix/uniswap-oracle-contracts/source/IUniswapV2Pair.sol';
 import "../libraries/FixedPoint.sol";
 
 // solhint-disable not-rely-on-time
 
+
+library BoringMath {
+    function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
+        require(b == 0 || (c = a * b) / b == a, "BoringMath: Mul Overflow");
+    }
+
+}
+
 // adapted from https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/examples/ExampleSlidingWindowOracle.sol
 
 contract SimpleSLPTWAP0Oracle is IOracle {
@@ -43,7 +50,6 @@ contract SimpleSLPTWAP0Oracle is IOracle {
     }
 
     // Get the latest exchange rate, if no valid (recent) rate is available, return false
-    /// @inheritdoc IOracle
     function get(bytes calldata data) external override returns (bool, uint256) {
         IUniswapV2Pair pair = abi.decode(data, (IUniswapV2Pair));
         uint32 blockTimestamp = uint32(block.timestamp);
@@ -69,8 +75,7 @@ contract SimpleSLPTWAP0Oracle is IOracle {
     }
 
     // Check the last exchange rate without any state changes
-    /// @inheritdoc IOracle
-    function peek(bytes calldata data) public view override returns (bool, uint256) {
+    function peek(bytes memory data) public view override returns (bool, uint256) {
         IUniswapV2Pair pair = abi.decode(data, (IUniswapV2Pair));
         uint32 blockTimestamp = uint32(block.timestamp);
         if (pairs[pair].blockTimestampLast == 0) {
@@ -89,20 +94,17 @@ contract SimpleSLPTWAP0Oracle is IOracle {
     }
 
     // Check the current spot exchange rate without any state changes
-    /// @inheritdoc IOracle
     function peekSpot(bytes calldata data) external view override returns (uint256 rate) {
         IUniswapV2Pair pair = abi.decode(data, (IUniswapV2Pair));
         (uint256 reserve0, uint256 reserve1, ) = pair.getReserves();
         rate = reserve1.mul(1e18) / reserve0;
     }
 
-    /// @inheritdoc IOracle
-    function name(bytes calldata) public view override returns (string memory) {
+    function name(bytes memory) public view override returns (string memory) {
         return "SushiSwap TWAP";
     }
 
-    /// @inheritdoc IOracle
-    function symbol(bytes calldata) public view override returns (string memory) {
+    function symbol(bytes memory) public view override returns (string memory) {
         return "S";
     }
 }

contracts/oracles/SimpleSLPTWAP1Oracle.sol

@@ -1,15 +1,21 @@
 // SPDX-License-Identifier: AGPL-3.0-only
 // Using the same Copyleft License as in the original Repository
-pragma solidity 0.6.12;
+pragma solidity 0.6.8;
 pragma experimental ABIEncoderV2;
 import "../interfaces/IOracle.sol";
-import "@boringcrypto/boring-solidity/contracts/libraries/BoringMath.sol";
 import "@sushiswap/core/contracts/uniswapv2/interfaces/IUniswapV2Factory.sol";
 import "@sushiswap/core/contracts/uniswapv2/interfaces/IUniswapV2Pair.sol";
 import "../libraries/FixedPoint.sol";
 
 // solhint-disable not-rely-on-time
 
+library BoringMath {
+    function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
+        require(b == 0 || (c = a * b) / b == a, "BoringMath: Mul Overflow");
+    }
+
+}
+
 // adapted from https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/examples/ExampleSlidingWindowOracle.sol
 
 contract SimpleSLPTWAP1Oracle is IOracle {
@@ -43,7 +49,6 @@ contract SimpleSLPTWAP1Oracle is IOracle {
     }
 
     // Get the latest exchange rate, if no valid (recent) rate is available, return false
-    /// @inheritdoc IOracle
     function get(bytes calldata data) external override returns (bool, uint256) {
         IUniswapV2Pair pair = abi.decode(data, (IUniswapV2Pair));
         uint32 blockTimestamp = uint32(block.timestamp);
@@ -69,8 +74,7 @@ contract SimpleSLPTWAP1Oracle is IOracle {
     }
 
     // Check the last exchange rate without any state changes
-    /// @inheritdoc IOracle
-    function peek(bytes calldata data) public view override returns (bool, uint256) {
+    function peek(bytes memory data) public view override returns (bool, uint256) {
         IUniswapV2Pair pair = abi.decode(data, (IUniswapV2Pair));
         uint32 blockTimestamp = uint32(block.timestamp);
         if (pairs[pair].blockTimestampLast == 0) {
@@ -89,20 +93,17 @@ contract SimpleSLPTWAP1Oracle is IOracle {
     }
 
     // Check the current spot exchange rate without any state changes
-    /// @inheritdoc IOracle
     function peekSpot(bytes calldata data) external view override returns (uint256 rate) {
         IUniswapV2Pair pair = abi.decode(data, (IUniswapV2Pair));
         (uint256 reserve0, uint256 reserve1, ) = pair.getReserves();
         rate = reserve0.mul(1e18) / reserve1;
     }
 
-    /// @inheritdoc IOracle
-    function name(bytes calldata) public view override returns (string memory) {
+    function name(bytes memory) public view override returns (string memory) {
         return "SushiSwap TWAP";
     }
 
-    /// @inheritdoc IOracle
-    function symbol(bytes calldata) public view override returns (string memory) {
+    function symbol(bytes memory) public view override returns (string memory) {
         return "S";
     }
 }

package.json

@@ -10,6 +10,7 @@
     },
     "dependencies": {
         "@boringcrypto/boring-solidity": "boringcrypto/BoringSolidity#371a01c11465eb1c881193c60a53c0bf15ee8a19",
+        "@keydonix/uniswap-oracle-contracts": "^1.0.6",
         "@sushiswap/bentobox-sdk": "sushiswap/bentobox-sdk#e3f809870b86afbd57e0930662221d2362a160db",
         "@sushiswap/core": "^1.4.2",
         "hardhat-deploy-ethers": "^0.3.0-beta.7"

settings.js

@@ -1,7 +1,45 @@
 module.exports = {
     hardhat: {
         solidity: {
+            compilers: [
+                {
+                    version: "0.6.12",
+                    settings: {
+                        optimizer: {
+                            enabled: true,
+                            runs: 200,
+                        },
+                    },
+                },
+                {
+                    version: "0.6.8",
+                    settings: {
+                        optimizer: {
+                            enabled: true,
+                            runs: 200,
+                        },
+                    },
+                }
+              ],
             overrides: {
+                "contracts/oracles/SimpleSLPTWAP1Oracle.sol": {
+                    version: "0.6.8",
+                    settings: {
+                        optimizer: {
+                            enabled: true,
+                            runs: 400,
+                        },
+                    },
+                },
+                "contracts/oracles/SimpleSLPTWAP0Oracle.sol": {
+                    version: "0.6.8",
+                    settings: {
+                        optimizer: {
+                            enabled: true,
+                            runs: 400,
+                        },
+                    },
+                },
                 "contracts/KashiPair.sol": {
                     version: "0.6.12",
                     settings: {

yarn.lock

@@ -426,6 +426,11 @@
     "@ethersproject/properties" "^5.0.7"
     "@ethersproject/strings" "^5.0.8"
 
+"@keydonix/uniswap-oracle-contracts@^1.0.6":
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/@keydonix/uniswap-oracle-contracts/-/uniswap-oracle-contracts-1.0.6.tgz#5fd371fad999c15d0ae687e28f37d8f396d6eb89"
+  integrity sha512-EJxtF9Jm9awWIfoTAqLLfOlv9JQ5rKSvQlJjGobUmYbcbl8a8c4/BsiWMmDLWcj2Be/eXipLd2bOQXLlJVTBAw==
+
 "@nodelib/[email protected]":
   version "2.1.4"
   resolved "https://registry.yarnpkg.com/@nodelib/fs.scandir/-/fs.scandir-2.1.4.tgz#d4b3549a5db5de2683e0c1071ab4f140904bbf69"