diff --git a/foundry.toml b/foundry.toml
index 6e4272e..8092bc9 100644
--- a/foundry.toml
+++ b/foundry.toml
@@ -19,6 +19,10 @@ skip = ["test/large/*.sol"]
 [profile.default.fuzz]
 seed = "0xe9cdc8fb2a2c0d1c046034d74d6498826ae3f1d9877353cf40d8a6a7aedfe875"
 
+[profile.coverage]
+optimizer = true
+optimizer_runs = 1_000_000
+
 [profile.large-test]
 via_ir = true
 match_path = "test/large/*.sol"
diff --git a/test/__fixtures/BaseTest.t.sol b/test/__fixtures/BaseTest.t.sol
index c3ca5ad..6a2b3d2 100644
--- a/test/__fixtures/BaseTest.t.sol
+++ b/test/__fixtures/BaseTest.t.sol
@@ -21,6 +21,8 @@ contract BaseTest is Test {
 
     GenericFactory internal _factory = new GenericFactory();
     ReservoirPair internal _pair;
+    ReservoirPair internal _pairBC;
+    ReservoirPair internal _pairCD;
 
     ReservoirPriceOracle internal _oracle =
         new ReservoirPriceOracle(DEFAULT_TWAP_PERIOD, DEFAULT_REWARD_GAS_AMOUNT, PriceType.CLAMPED_PRICE);
@@ -54,6 +56,16 @@ contract BaseTest is Test {
         _tokenA.mint(address(_pair), 103e6);
         _tokenB.mint(address(_pair), 10_189e18);
         _pair.mint(address(this));
+
+        _pairBC = ReservoirPair(_createPair(address(_tokenB), address(_tokenC), 0));
+        _tokenB.mint(address(_pairBC), 102_303e18);
+        _tokenC.mint(address(_pairBC), 292e10);
+        _pairBC.mint(address(this));
+
+        _pairCD = ReservoirPair(_createPair(address(_tokenC), address(_tokenD), 0));
+        _tokenC.mint(address(_pairCD), 991_102_221e10);
+        _tokenD.mint(address(_pairCD), 937_991_222e6);
+        _pairCD.mint(address(this));
     }
 
     function _createPair(address aTokenA, address aTokenB, uint256 aCurveId) internal returns (address rPair) {
diff --git a/test/unit/ReservoirPriceOracle.t.sol b/test/unit/ReservoirPriceOracle.t.sol
index 5ade774..2af3f8e 100644
--- a/test/unit/ReservoirPriceOracle.t.sol
+++ b/test/unit/ReservoirPriceOracle.t.sol
@@ -94,6 +94,8 @@ contract ReservoirPriceOracleTest is BaseTest {
         lRewardThreshold[0] = 200; // 2%
 
         _oracle.designatePair(address(_tokenB), address(_tokenA), _pair);
+        _oracle.designatePair(address(_tokenB), address(_tokenC), _pairBC);
+        _oracle.designatePair(address(_tokenD), address(_tokenC), _pairCD);
         _oracle.setRoute(address(_tokenA), address(_tokenB), lRoute, lRewardThreshold);
     }
 
@@ -983,6 +985,38 @@ contract ReservoirPriceOracleTest is BaseTest {
         _oracle.updatePrice(address(_tokenB), address(_tokenC), address(0));
     }
 
+    function testUpdatePrice_WriteToNonSimpleRoute() external {
+        // arrange
+        uint16[] memory lRewardThresholds = new uint16[](2);
+        lRewardThresholds[0] = lRewardThresholds[1] = 1;
+        address[] memory lRoute = new address[](3);
+        lRoute[0] = address(_tokenA);
+        lRoute[1] = address(_tokenB);
+        lRoute[2] = address(_tokenC);
+
+        _oracle.setRoute(address(_tokenA), address(_tokenC), lRoute, lRewardThresholds);
+
+        // then we change the original B->C route with B->D->C
+        address[] memory lModifiedRoute = new address[](3);
+        lModifiedRoute[0] = address(_tokenB);
+        lModifiedRoute[1] = address(_tokenD);
+        lModifiedRoute[2] = address(_tokenC);
+        _oracle.setRoute(address(_tokenB), address(_tokenC), lModifiedRoute, lRewardThresholds);
+
+        skip(10);
+        _pair.sync();
+        _pairBC.sync();
+        _pairCD.sync();
+        skip(_oracle.twapPeriod());
+        _pair.sync();
+        _pairBC.sync();
+        _pairCD.sync();
+
+        // act & assert
+        vm.expectRevert(OracleErrors.WriteToNonSimpleRoute.selector);
+        _oracle.updatePrice(address(_tokenA), address(_tokenC), address(0));
+    }
+
     function testUpdatePrice_NoPath() external {
         vm.expectRevert(OracleErrors.NoPath.selector);
         _oracle.updatePrice(address(_tokenD), address(_tokenC), address(0));