diff --git a/flat/IStakingRewards.f.sol b/flat/IStakingRewards.f.sol
new file mode 100644
index 0000000..9abf8ba
--- /dev/null
+++ b/flat/IStakingRewards.f.sol
@@ -0,0 +1,32 @@
+// hevm: flattened sources of src/interfaces/IStakingRewards.sol
+
+pragma solidity >=0.4.24;
+
+////// src/interfaces/IStakingRewards.sol
+/* pragma solidity >=0.4.24; */
+
+interface IStakingRewards {
+    // Views
+    function lastTimeRewardApplicable() external view returns (uint256);
+
+    function rewardPerToken() external view returns (uint256);
+
+    function earned(address account) external view returns (uint256);
+
+    function getRewardForDuration() external view returns (uint256);
+
+    function totalSupply() external view returns (uint256);
+
+    function balanceOf(address account) external view returns (uint256);
+
+    // Mutative
+
+    function stake(uint256 amount) external;
+
+    function withdraw(uint256 amount) external;
+
+    function getReward() external;
+
+    function exit() external;
+}
+
diff --git a/flat/KTONStakingRewards.f.sol b/flat/KTONStakingRewards.f.sol
index 22d4aa7..2788d17 100644
--- a/flat/KTONStakingRewards.f.sol
+++ b/flat/KTONStakingRewards.f.sol
@@ -426,9 +426,10 @@ contract ReentrancyGuard {
 /* pragma solidity ^0.5.16; */
 
 contract RewardsDistributionRecipient {
-    address public rewardsDistribution;
+    // "sc/ktnstk" in bytes.
+    address public constant rewardsDistribution = 0x73632F6b746e73746B0000000000000000000000;
 
-    function notifyRewardAmount() external payable;
+    function notifyRewardAmount() external;
 
     modifier onlyRewardsDistribution() {
         require(msg.sender == rewardsDistribution, "Caller is not RewardsDistribution contract");
@@ -483,7 +484,7 @@ contract KTONStakingRewards is IStakingRewards, RewardsDistributionRecipient, Re
 
     /* ========== STATE VARIABLES ========== */
 
-    IERC20 public stakingToken;
+    IERC20 public constant stakingToken = IERC20(0x0000000000000000000000000000000000000402);
     uint256 public periodFinish = 0;
     uint256 public rewardRate = 0;
     uint256 public rewardsDuration = 7200;
@@ -496,13 +497,6 @@ contract KTONStakingRewards is IStakingRewards, RewardsDistributionRecipient, Re
     uint256 private _totalSupply;
     mapping(address => uint256) private _balances;
 
-    /* ========== CONSTRUCTOR ========== */
-
-    constructor(address _rewardsDistribution, address _stakingToken) public {
-        stakingToken = IERC20(_stakingToken);
-        rewardsDistribution = _rewardsDistribution;
-    }
-
     /* ========== VIEWS ========== */
 
     function totalSupply() external view returns (uint256) {
@@ -570,9 +564,7 @@ contract KTONStakingRewards is IStakingRewards, RewardsDistributionRecipient, Re
 
     /* ========== RESTRICTED FUNCTIONS ========== */
 
-    function notifyRewardAmount() external payable onlyRewardsDistribution updateReward(address(0)) {
-        uint256 reward = msg.value;
-        require(reward >= rewardsDuration, "Provided reward too low");
+    function notifyRewardAmount(uint256 reward) external onlyRewardsDistribution updateReward(address(0)) {
         if (block.timestamp >= periodFinish) {
             rewardRate = reward.div(rewardsDuration);
         } else {
diff --git a/flat/RewardsDistributionRecipient.f.sol b/flat/RewardsDistributionRecipient.f.sol
new file mode 100644
index 0000000..a5b14c7
--- /dev/null
+++ b/flat/RewardsDistributionRecipient.f.sol
@@ -0,0 +1,19 @@
+// hevm: flattened sources of src/RewardsDistributionRecipient.sol
+
+pragma solidity >=0.5.16 <0.6.0;
+
+////// src/RewardsDistributionRecipient.sol
+/* pragma solidity ^0.5.16; */
+
+contract RewardsDistributionRecipient {
+    // "sc/ktnstk" in bytes.
+    address public constant rewardsDistribution = 0x73632F6b746e73746B0000000000000000000000;
+
+    function notifyRewardAmount() external;
+
+    modifier onlyRewardsDistribution() {
+        require(msg.sender == rewardsDistribution, "Caller is not RewardsDistribution contract");
+        _;
+    }
+}
+
diff --git a/src/KTONStakingRewards.sol b/src/KTONStakingRewards.sol
index 866e3e6..e719ba9 100644
--- a/src/KTONStakingRewards.sol
+++ b/src/KTONStakingRewards.sol
@@ -96,9 +96,7 @@ contract KTONStakingRewards is IStakingRewards, RewardsDistributionRecipient, Re
 
     /* ========== RESTRICTED FUNCTIONS ========== */
 
-    function notifyRewardAmount() external payable onlyRewardsDistribution updateReward(address(0)) {
-        uint256 reward = msg.value;
-        require(reward >= rewardsDuration, "Provided reward too low");
+    function notifyRewardAmount(uint256 reward) external onlyRewardsDistribution updateReward(address(0)) {
         if (block.timestamp >= periodFinish) {
             rewardRate = reward.div(rewardsDuration);
         } else {
diff --git a/src/RewardsDistributionRecipient.sol b/src/RewardsDistributionRecipient.sol
index 9319fb8..1c9d1e1 100644
--- a/src/RewardsDistributionRecipient.sol
+++ b/src/RewardsDistributionRecipient.sol
@@ -1,10 +1,10 @@
 pragma solidity ^0.5.16;
 
 contract RewardsDistributionRecipient {
-    // "KTONStakingRewards" in bytes.
-    address public constant rewardsDistribution = 0x4b544f4e5374616b696e67526577617264730000;
+    // "sc/ktnstk" in bytes.
+    address public constant rewardsDistribution = 0x73632F6b746e73746B0000000000000000000000;
 
-    function notifyRewardAmount() external payable;
+    function notifyRewardAmount() external;
 
     modifier onlyRewardsDistribution() {
         require(msg.sender == rewardsDistribution, "Caller is not RewardsDistribution contract");