diff --git a/.gitignore b/.gitignore
index 3269660..64c78d5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,6 @@ out/
 
 # Dotenv file
 .env
+
+# Coverage file
+lcov.info
\ No newline at end of file
diff --git a/src/MaglevBase.sol b/src/MaglevBase.sol
index 2629ddc..f799be8 100644
--- a/src/MaglevBase.sol
+++ b/src/MaglevBase.sol
@@ -5,8 +5,9 @@ import {EVCUtil} from "evc/utils/EVCUtil.sol";
 import {IEVC} from "evc/interfaces/IEthereumVaultConnector.sol";
 import {IEVault, IERC20, IBorrowing, IERC4626, IRiskManager} from "evk/EVault/IEVault.sol";
 import {IUniswapV2Callee} from "./interfaces/IUniswapV2Callee.sol";
+import {IMaglevBase} from "./interfaces/IMaglevBase.sol";
 
-abstract contract MaglevBase is EVCUtil {
+abstract contract MaglevBase is IMaglevBase, EVCUtil {
     address public immutable vault0;
     address public immutable vault1;
     address public immutable asset0;
@@ -51,6 +52,9 @@ abstract contract MaglevBase is EVCUtil {
         vault1 = params.vault1;
         asset0 = IEVault(vault0).asset();
         asset1 = IEVault(vault1).asset();
+
+        require(asset0 != asset1, UnsupportedPair());
+
         myAccount = params.myAccount;
         reserve0 = offsetReserve(params.debtLimit0, vault0);
         reserve1 = offsetReserve(params.debtLimit1, vault1);
@@ -82,7 +86,7 @@ abstract contract MaglevBase is EVCUtil {
 
         // Invoke callback
 
-        if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
+        if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(_msgSender(), amount0Out, amount1Out, data);
 
         // Deposit all available funds, adjust received amounts downward to collect fees
 
diff --git a/src/MaglevEulerSwap.sol b/src/MaglevEulerSwap.sol
index b56b72a..3d8aa04 100644
--- a/src/MaglevEulerSwap.sol
+++ b/src/MaglevEulerSwap.sol
@@ -3,8 +3,9 @@ pragma solidity ^0.8.27;
 
 import {Math} from "@openzeppelin/contracts/utils/math/Math.sol";
 import {MaglevBase} from "./MaglevBase.sol";
+import {IMaglevEulerSwap} from "./interfaces/IMaglevEulerSwap.sol";
 
-contract MaglevEulerSwap is MaglevBase {
+contract MaglevEulerSwap is IMaglevEulerSwap, MaglevBase {
     uint256 public immutable priceX;
     uint256 public immutable priceY;
     uint256 public immutable concentrationX;
diff --git a/src/interfaces/IMaglevBase.sol b/src/interfaces/IMaglevBase.sol
new file mode 100644
index 0000000..0bc4dcc
--- /dev/null
+++ b/src/interfaces/IMaglevBase.sol
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity >=0.8.0;
+
+interface IMaglevBase {
+    function configure() external;
+    function swap(uint256 amount0Out, uint256 amount1Out, address to, bytes calldata data) external;
+    function quoteExactInput(address tokenIn, address tokenOut, uint256 amountIn) external view returns (uint256);
+    function quoteExactOutput(address tokenIn, address tokenOut, uint256 amountOut) external view returns (uint256);
+
+    function vault0() external view returns (address);
+    function vault1() external view returns (address);
+    function asset0() external view returns (address);
+    function asset1() external view returns (address);
+    function myAccount() external view returns (address);
+    function debtLimit0() external view returns (uint112);
+    function debtLimit1() external view returns (uint112);
+    function feeMultiplier() external view returns (uint256);
+    function reserve0() external view returns (uint112);
+    function reserve1() external view returns (uint112);
+}
diff --git a/src/interfaces/IMaglevEulerSwap.sol b/src/interfaces/IMaglevEulerSwap.sol
new file mode 100644
index 0000000..3902449
--- /dev/null
+++ b/src/interfaces/IMaglevEulerSwap.sol
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity >=0.8.0;
+
+import {IMaglevBase} from "./IMaglevBase.sol";
+
+interface IMaglevEulerSwap is IMaglevBase {
+    function priceX() external view returns (uint256);
+    function priceY() external view returns (uint256);
+    function concentrationX() external view returns (uint256);
+    function concentrationY() external view returns (uint256);
+    function initialReserve0() external view returns (uint112);
+    function initialReserve1() external view returns (uint112);
+}
diff --git a/test/UniswapV2Call.t.sol b/test/UniswapV2Call.t.sol
new file mode 100644
index 0000000..11516d3
--- /dev/null
+++ b/test/UniswapV2Call.t.sol
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+pragma solidity ^0.8.24;
+
+import {IUniswapV2Callee} from "../src/interfaces/IUniswapV2Callee.sol";
+// import {Test, console} from "forge-std/Test.sol";
+import {MaglevTestBase} from "./MaglevTestBase.t.sol";
+import {MaglevEulerSwap as Maglev} from "../src/MaglevEulerSwap.sol";
+
+contract UniswapV2CallTest is MaglevTestBase {
+    Maglev public maglev;
+    SwapCallbackTest swapCallback;
+
+    function setUp() public virtual override {
+        super.setUp();
+
+        createMaglev(50e18, 50e18, 0, 1e18, 1e18, 0.4e18, 0.85e18);
+
+        swapCallback = new SwapCallbackTest();
+    }
+
+    function createMaglev(
+        uint112 debtLimit0,
+        uint112 debtLimit1,
+        uint256 fee,
+        uint256 px,
+        uint256 py,
+        uint256 cx,
+        uint256 cy
+    ) internal {
+        vm.prank(creator);
+        maglev = new Maglev(
+            getMaglevBaseParams(debtLimit0, debtLimit1, fee),
+            Maglev.EulerSwapParams({priceX: px, priceY: py, concentrationX: cx, concentrationY: cy})
+        );
+
+        vm.prank(holder);
+        evc.setAccountOperator(holder, address(maglev), true);
+
+        vm.prank(anyone);
+        maglev.configure();
+    }
+
+    function test_callback() public {
+        uint256 amountIn = 1e18;
+        uint256 amountOut = maglev.quoteExactInput(address(assetTST), address(assetTST2), amountIn);
+        assertApproxEqAbs(amountOut, 0.9974e18, 0.0001e18);
+
+        assetTST.mint(address(this), amountIn);
+        assetTST.transfer(address(maglev), amountIn);
+
+        uint256 randomBalance = 3e18;
+        vm.prank(anyone);
+        swapCallback.executeSwap(maglev, 0, amountOut, abi.encode(randomBalance));
+        assertEq(assetTST2.balanceOf(address(swapCallback)), amountOut);
+        assertEq(swapCallback.callbackSender(), address(swapCallback));
+        assertEq(swapCallback.callbackAmount0(), 0);
+        assertEq(swapCallback.callbackAmount1(), amountOut);
+        assertEq(swapCallback.randomBalance(), randomBalance);
+    }
+}
+
+contract SwapCallbackTest is IUniswapV2Callee {
+    address public callbackSender;
+    uint256 public callbackAmount0;
+    uint256 public callbackAmount1;
+    uint256 public randomBalance;
+
+    function executeSwap(Maglev maglev, uint256 amountIn, uint256 amountOut, bytes calldata data) external {
+        maglev.swap(amountIn, amountOut, address(this), data);
+    }
+
+    function uniswapV2Call(address sender, uint256 amount0, uint256 amount1, bytes calldata data) external {
+        randomBalance = abi.decode(data, (uint256));
+
+        callbackSender = sender;
+        callbackAmount0 = amount0;
+        callbackAmount1 = amount1;
+    }
+
+    function test_avoid_coverage() public pure {
+        return;
+    }
+}