Updated dependency ordering using a linearizer script, which is now here: https://github.com/hysz/SmartContractLinearizer

contracts/staking/contracts/src/Staking.sol

@@ -31,14 +31,18 @@ import "./core/MixinRewards.sol";
 
 
 contract Staking is
+    IStakingEvents,
+    MixinDeploymentConstants,
+    MixinConstants,
+    MixinStorage,
     MixinEpoch,
-    MixinExchange,
-    MixinZrxVault,
     MixinRewardVault,
+    MixinZrxVault,
+    MixinExchange,
     MixinStakeBalances,
-    MixinStake,
     MixinPools,
     MixinRewards,
+    MixinStake,
     MixinFees
 {
 

contracts/staking/contracts/src/StakingProxy.sol

@@ -23,8 +23,8 @@ import "./interfaces/IStakingProxy.sol";
 
 
 contract StakingProxy is
-    IStakingProxy,
+    MixinStorage,
-    MixinStorage
+    IStakingProxy
 {
     address constant NIL_ADDRESS = 0x0000000000000000000000000000000000000000;
 

contracts/staking/contracts/src/core/MixinExchange.sol

@@ -25,9 +25,7 @@ import "../immutable/MixinStorage.sol";
 
 
 contract MixinExchange is
-    // interfaces
     IStakingEvents,
-    // immutables
     MixinConstants,
     MixinStorage
 {

contracts/staking/contracts/src/core/MixinFees.sol

@@ -32,17 +32,12 @@ import "../interfaces/IStructs.sol";
 
 
 contract MixinFees is
-    // interfaces
     IStakingEvents,
-    IStructs,
-    // immutables
     MixinConstants,
     MixinStorage,
-    // standalones
     MixinEpoch,
-    MixinExchange,
     MixinRewardVault,
-    // staking logic
+    MixinExchange,
     MixinStakeBalances,
     MixinPools
 {
@@ -91,7 +86,7 @@ contract MixinFees is
     {
         // Step 1 - compute total fees this epoch
         uint256 numberOfActivePoolIds = activePoolIdsThisEpoch.length;
-        ActivePool[] memory activePoolIds = new ActivePool[](activePoolIdsThisEpoch.length);
+        IStructs.ActivePool[] memory activePoolIds = new IStructs.ActivePool[](activePoolIdsThisEpoch.length);
         uint256 totalFees = 0;
         for (uint i = 0; i != numberOfActivePoolIds; i++) {
             activePoolIds[i].poolId = activePoolIdsThisEpoch[i];

contracts/staking/contracts/src/core/MixinPools.sol

@@ -33,12 +33,9 @@ import "./MixinRewardVault.sol";
 
 
 contract MixinPools is
-    // interfaces
     IStakingEvents,
-    // immutables
     MixinConstants,
     MixinStorage,
-    // standalone
     MixinRewardVault
 {
 
@@ -63,7 +60,7 @@ contract MixinPools is
         nextPoolId = _computeNextPoolId(poolId);
 
         // 
-        Pool memory pool = Pool({
+        IStructs.Pool memory pool = IStructs.Pool({
             operatorAddress: operatorAddress,
             operatorShare: operatorShare
         });
@@ -125,7 +122,7 @@ contract MixinPools is
         view
         returns (bytes32 approvalHash)
     {
-        StakingPoolApproval memory approval = StakingPoolApproval({
+        IStructs.StakingPoolApproval memory approval = IStructs.StakingPoolApproval({
             poolId: poolId,
             makerAddress: makerAddress
         });
@@ -182,7 +179,7 @@ contract MixinPools is
     function _getPool(bytes32 poolId)
         internal
         view
-        returns (Pool memory pool)
+        returns (IStructs.Pool memory pool)
     {
         pool = poolById[poolId];
         return pool;

contracts/staking/contracts/src/core/MixinRewards.sol

@@ -22,18 +22,15 @@ import "../libs/LibSafeMath.sol";
 import "../libs/LibRewardMath.sol";
 import "../immutable/MixinStorage.sol";
 import "../immutable/MixinConstants.sol";
-import "../interfaces/IStakingEvents.sol";
 import "./MixinStakeBalances.sol";
 import "./MixinRewardVault.sol";
 import "./MixinPools.sol";
 
+
 contract MixinRewards is
-    // immutables
     MixinConstants,
     MixinStorage,
-    // standalones
     MixinRewardVault,
-    // logic
     MixinStakeBalances,
     MixinPools
 {

contracts/staking/contracts/src/core/MixinStake.sol

@@ -30,16 +30,12 @@ import "./MixinStakeBalances.sol";
 
 
 contract MixinStake is
-    // interfaces
     IStakingEvents,
-    // immutables
     MixinConstants,
     MixinStorage,
-    // standalone
     MixinEpoch,
-    MixinZrxVault,
     MixinRewardVault,
-    // logic
+    MixinZrxVault,
     MixinStakeBalances
 {
 
@@ -268,7 +264,7 @@ contract MixinStake is
     function _timelockStake(address owner, uint256 amount)
         private
     {
-        (Timelock memory ownerTimelock,) = _getSynchronizedTimelock(owner);
+        (IStructs.Timelock memory ownerTimelock,) = _getSynchronizedTimelock(owner);
         uint96 downcastAmount = amount._downcastToUint96();
         ownerTimelock.total += downcastAmount;
         timelockedStakeByOwner[owner] = ownerTimelock;
@@ -277,7 +273,7 @@ contract MixinStake is
     function _syncTimelockedStake(address owner)
         private
     {
-        (Timelock memory ownerTimelock, bool isOutOfSync) = _getSynchronizedTimelock(owner);
+        (IStructs.Timelock memory ownerTimelock, bool isOutOfSync) = _getSynchronizedTimelock(owner);
         if (!isOutOfSync) {
             return;
         }

contracts/staking/contracts/src/core/MixinStakeBalances.sol

@@ -119,7 +119,7 @@ contract MixinStakeBalances is
         view
         returns (uint256)
     {
-        (Timelock memory timelock,) = _getSynchronizedTimelock(owner);
+        (IStructs.Timelock memory timelock,) = _getSynchronizedTimelock(owner);
         return timelock.total;
     }
 
@@ -128,7 +128,7 @@ contract MixinStakeBalances is
         view
         returns (uint256)
     {
-        (Timelock memory timelock,) = _getSynchronizedTimelock(owner);
+        (IStructs.Timelock memory timelock,) = _getSynchronizedTimelock(owner);
         return timelock.lockedAt;
     }
 

contracts/staking/contracts/src/immutable/MixinStorage.sol

@@ -25,7 +25,6 @@ import "../interfaces/IStructs.sol";
 
 
 contract MixinStorage is
-    IStructs,
     MixinConstants
 {
 
@@ -46,7 +45,7 @@ contract MixinStorage is
     mapping (address => uint256) activeStakeByOwner;
 
     // mapping from Owner to Amount Timelocked
-    mapping (address => Timelock) timelockedStakeByOwner;
+    mapping (address => IStructs.Timelock) timelockedStakeByOwner;
 
     // mapping from Owner to Amount Delegated
     mapping (address => uint256) delegatedStakeByOwner;
@@ -64,7 +63,7 @@ contract MixinStorage is
     bytes32 nextPoolId = INITIAL_POOL_ID;
 
     // mapping from Pool Id to Pool
-    mapping (bytes32 => Pool) poolById;
+    mapping (bytes32 => IStructs.Pool) poolById;
 
     // mapping from Maker Address to Pool Id
     // A Maker can only hold a single token

contracts/staking/contracts/src/libs/LibTimelock.sol

@@ -1,99 +0,0 @@
-/*
-
-  Copyright 2018 ZeroEx Intl.
-
-  Licensed under the Apache License, Version 2.0 (the "License");
-  you may not use this file except in compliance with the License.
-  You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing, software
-  distributed under the License is distributed on an "AS IS" BASIS,
-  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  See the License for the specific language governing permissions and
-  limitations under the License.
-
-*/
-
-pragma solidity ^0.5.5;
-
-import "../interfaces/IStructs.sol";
-import "@0x/contracts-utils/contracts/src/SafeMath.sol";
-
-
-contract MixinTimelock is
-    IStructs,
-    SafeMath
-{
-
-    // Epoch | lockedAt  | total | pending | current | timelock() | withdraw() | available()
-    // 0     | 0         | 0     | 0       | 0       |            |            | 0
-    // 1     | 1         | 5     | 0       | 0       | +5         |            | 0
-    // 2     | 1         | 5     | 0       | 0       |            |            | 0
-    // 2     | 2         | 15    | 5       | 0       | +10        |            | 0
-    // 3     | 2         | 15    | 5       | 0       |            |            | 5
-    // 3     | 3         | 30    | 15      | 5       | +15        |            | 5
-    // 4     | 3         | 30    | 15      | 5       |            |            | 15
-    // 5     | 3         | 30    | 15      | 5       |            |            | 30
-    // 5     | 5         | 30    | 30      | 30      | +0 *       |            | 30
-    // 6     | 6         | 50    | 30      | 30      | +20        |            | 30
-    // 6     | 6         | 20    | 0       | 0       |            | -30        | 0
-    // 7     | 6         | 20    | 0       | 0       |            |            | 0
-    // 8     | 6         | 20    | 0       | 0       |            |            | 20
-
-    
-    function _add(Timelock memory timelock, uint256 amount)
-        internal
-        returns (uint256)
-    {
-        timelock.total += amount;
-    }
-
-    function _sub(Timelock memory timelock, uint256 amount)
-        internal
-        returns (uint256)
-    {
-        
-    }
-
-    
-
-    function _subTimelockedStake(address owner, uint256 amount)
-        internal
-    {
-        
-    }
-
-    function _addTimelockedStake(address owner, uint256 amount)
-        internal
-    {
-        timelockedStakeByOwner[owner] = safeAdd(timelockedStakeByOwner[owner], amount);
-
-        // update timelock
-        uint64 currentTimelockPeriod = _getTimelockPeriod();
-        Timelock memory timelock = timelocksByOwner[owner];
-       
-    }
-
-    function _getAvailableTimelockedStake(address owner)
-        internal
-        returns (uint256)
-    {
-
-    }
-
-    function _getPendingTimelockedStake(address owner)
-        internal
-        returns (uint256)
-    {
-        
-    }
-
-    function _getTotalTimelockedStake(address owner)
-        internal
-        returns (uint256)
-    {
-        
-    }
-}