diff --git a/bun.lockb b/bun.lockb
index dfc7565..c4ed947 100755
Binary files a/bun.lockb and b/bun.lockb differ
diff --git a/foundry.toml b/foundry.toml
index bf5d8bc..a7b65ad 100644
--- a/foundry.toml
+++ b/foundry.toml
@@ -47,7 +47,7 @@ bnb_smart_chain = "https://bsc-dataseed.binance.org"
 gnosis_chain = "https://rpc.gnosischain.com"
 goerli = "https://goerli.infura.io/v3/${API_KEY_INFURA}"
 localhost = "http://localhost:8545"
-mainnet = "https://eth-mainnet.g.alchemy.com/v2/${API_KEY_ALCHEMY}"
+mainnet = "https://mainnet.infura.io/v3/${API_KEY_INFURA}"
 optimism = "https://optimism-mainnet.infura.io/v3/${API_KEY_INFURA}"
 polygon = "https://polygon-mainnet.infura.io/v3/${API_KEY_INFURA}"
 sepolia = "https://sepolia.infura.io/v3/${API_KEY_INFURA}"
diff --git a/package.json b/package.json
index 9a1ce1c..bf7d761 100644
--- a/package.json
+++ b/package.json
@@ -7,14 +7,15 @@
     "url": "https://github.com/PaulRBerg"
   },
   "dependencies": {
-    "@openzeppelin/contracts": "^5.0.1"
+    "@openzeppelin/contracts": "4.9.3",
+    "@openzeppelin/contracts-upgradeable": "4.9.3"
   },
   "devDependencies": {
     "@prb/test": "^0.6.4",
     "forge-std": "github:foundry-rs/forge-std#v1.7.5",
     "prettier": "^3.0.0",
     "solhint": "^3.6.2",
-    "@pendle/core-v2": "^4.1.0"
+    "@pendle/core-v2": "^4.2.6"
   },
   "keywords": [
     "blockchain",
diff --git a/remappings.txt b/remappings.txt
index 31c4484..8dfbacb 100644
--- a/remappings.txt
+++ b/remappings.txt
@@ -1,4 +1,5 @@
 @openzeppelin/contracts/=node_modules/@openzeppelin/contracts/
+@openzeppelin/contracts-upgradeable/=node_modules/@openzeppelin/contracts-upgradeable/
 @prb/test/=node_modules/@prb/test/
 forge-std/=node_modules/forge-std/
 @pendle/core-v2/=node_modules/@pendle/core-v2/
\ No newline at end of file
diff --git a/test/OracleSample.sol b/test/OracleSample.sol
new file mode 100644
index 0000000..1b4d186
--- /dev/null
+++ b/test/OracleSample.sol
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity >=0.8.23 <0.9.0;
+
+import { PRBTest } from "@prb/test/src/PRBTest.sol";
+import { console2 as console } from "forge-std/src/console2.sol";
+import { StdCheats } from "forge-std/src/StdCheats.sol";
+import "@pendle/core-v2/contracts/interfaces/IPAllActionV3.sol";
+import "@pendle/core-v2/contracts/interfaces/IPMarket.sol";
+import "@pendle/core-v2/contracts/oracles/PendlePtLpOracle.sol";
+import "../src/StructGen.sol";
+import { AggregatorV2V3Interface as IChainlinkAggregator } from
+    "@chainlink/contracts/src/v0.8/interfaces/AggregatorV2V3Interface.sol";
+
+contract OracleSample is PRBTest, StdCheats, StructGen {
+    using PendlePtOracleLib for IPMarket;
+    using PendleLpOracleLib for IPMarket;
+
+    IPMarket public constant market = IPMarket(0xE11f9786B06438456b044B3E21712228ADcAA0D1);
+    PendlePtLpOracle public constant oracle = PendlePtLpOracle(0x1Fd95db7B7C0067De8D45C0cb35D59796adfD187);
+    IChainlinkAggregator public constant feed = IChainlinkAggregator(0xA736eAe8805dDeFFba40cAB8c99bCB309dEaBd9B); // weETH
+        // to ETH, Redstone
+    uint8 public feedDecimals;
+
+    uint32 public constant twapDuration = 900;
+
+    IStandardizedYield public SY;
+    IPPrincipalToken public PT;
+    IPYieldToken public YT;
+
+    function setUp() public virtual {
+        vm.createSelectFork({ urlOrAlias: "arbitrum", blockNumber: 192_001_277 });
+        (SY, PT, YT) = IPMarket(market).readTokens();
+        _test_oracle_ready(address(market), twapDuration);
+        feedDecimals = uint8(feed.decimals());
+    }
+
+    function test_get_prices_use_library() external view {
+        uint256 ptRateInEEth = IPMarket(market).getPtToAssetRate(twapDuration);
+        console.log("1 PT = %s eEth (base 1e18)", ptRateInEEth);
+
+        uint256 ptRateInWeEth = IPMarket(market).getPtToSyRate(twapDuration);
+        console.log("1 PT = %s weEth (base 1e18)", ptRateInWeEth);
+
+        uint256 lpRateInEEth = IPMarket(market).getLpToAssetRate(twapDuration);
+        console.log("1 LP = %s eEth (base 1e18)", lpRateInEEth);
+
+        uint256 lpRateInWeEth = IPMarket(market).getLpToSyRate(twapDuration);
+        console.log("1 LP = %s weEth (base 1e18)", lpRateInWeEth);
+    }
+
+    function test_get_price_SY_multiply_by_external_price() external view {
+        uint256 ptRateInWeEth = IPMarket(market).getPtToSyRate(twapDuration); // 1 SY-weETH = 1 weETH
+        uint256 ptRateInEth = ptRateInWeEth * uint256(feed.latestAnswer()) / (10 ** feedDecimals);
+        console.log("1 PT = %s ETH (base 1e18)", ptRateInEth);
+    }
+
+    function test_get_price_asset_multiply_by_external_price() external view {
+        address aUSDCMarket = 0xBa4A858d664Ddb052158168DB04AFA3cFF5CFCC8;
+        IChainlinkAggregator aUSDCFeed = IChainlinkAggregator(0x50834F3163758fcC1Df9973b6e91f0F0F0434aD3); // aUSDC to
+            // USD, Chainlink
+
+        uint256 ptRateInUSDC = IPMarket(aUSDCMarket).getPtToAssetRate(twapDuration); // Have to get in asset because
+            // SY-aUSDC ~= aUSDC and doesn't have a price
+
+        uint256 ptRateInUsd = ptRateInUSDC * uint256(aUSDCFeed.latestAnswer()) / (10 ** 8);
+        console.log("1 PT = %s USD (base 1e18)", ptRateInUsd);
+    }
+
+    function test_get_LP_price_use_library() external view {
+        uint256 lpRateInEEth = IPMarket(market).getLpToAssetRate(twapDuration);
+        console.log("1 LP = %s eEth (base 1e18)", lpRateInEEth);
+
+        uint256 lpRateInWeEth = IPMarket(market).getLpToSyRate(twapDuration);
+        console.log("1 LP = %s weEth (base 1e18)", lpRateInWeEth);
+
+        uint256 lpRateInEth = lpRateInWeEth * uint256(feed.latestAnswer()) / (10 ** feedDecimals);
+        console.log("1 LP = %s ETH (base 1e18)", lpRateInEth);
+    }
+
+    /// @dev more gas consuming than using library, same results
+    function test_get_prices_use_oracle_contract() external view {
+        uint256 ptRateInEEth = oracle.getPtToAssetRate(address(market), twapDuration);
+        console.log("1 PT = %s eEth (base 1e18)", ptRateInEEth);
+
+        uint256 ptRateInWeEth = oracle.getPtToSyRate(address(market), twapDuration);
+        console.log("1 PT = %s weEth (base 1e18)", ptRateInWeEth);
+
+        uint256 lpRateInEEth = oracle.getLpToAssetRate(address(market), twapDuration);
+        console.log("1 LP = %s eEth (base 1e18)", lpRateInEEth);
+
+        uint256 lpRateInWeEth = oracle.getLpToSyRate(address(market), twapDuration);
+        console.log("1 LP = %s weEth (base 1e18)", lpRateInWeEth);
+    }
+
+    /// @dev Call only once for each (market, duration). Once successful, it's permanently valid (also for any shorter
+    /// duration).
+    function _test_oracle_ready(address marketToCheck, uint32 duration) public view {
+        (bool increaseCardinalityRequired,, bool oldestObservationSatisfied) =
+            oracle.getOracleState(marketToCheck, duration);
+
+        if (increaseCardinalityRequired) {
+            // It's required to call IPMarket(market).increaseObservationsCardinalityNext(cardinalityRequired) and wait
+            // for at least the twapDuration, to allow data population.
+        }
+
+        if (!oldestObservationSatisfied) {
+            // It's necessary to wait for at least the twapDuration, to allow data population.
+        }
+
+        assert(!increaseCardinalityRequired);
+        assert(oldestObservationSatisfied);
+    }
+}