diff --git a/circuit/miximus.cpp b/circuit/miximus.cpp
index 79bc282..b88f8c1 100644
--- a/circuit/miximus.cpp
+++ b/circuit/miximus.cpp
@@ -87,7 +87,7 @@ namespace ethsnarks {
 class mod_miximus : public GadgetT
 {
 public:
-    typedef MiMC_hash_gadget HashT;
+    typedef MiMC_e7_hash_gadget HashT;
     const size_t tree_depth = MIXIMUS_TREE_DEPTH;
 
     // public inputs
diff --git a/ethsnarks b/ethsnarks
index 450bb9b..2cade96 160000
--- a/ethsnarks
+++ b/ethsnarks
@@ -1 +1 @@
-Subproject commit 450bb9be7123491f8ca2dddb46b7059466fafbb5
+Subproject commit 2cade96d77437b4cb9999d82b8267364806cba60
diff --git a/solidity/contracts/Miximus.sol b/solidity/contracts/Miximus.sol
index ffc0725..4755b5a 100644
--- a/solidity/contracts/Miximus.sol
+++ b/solidity/contracts/Miximus.sol
@@ -21,7 +21,7 @@ pragma solidity ^0.5.0;
 
 import "../../ethsnarks/contracts/Verifier.sol";
 import "../../ethsnarks/contracts/MerkleTree.sol";
-import "../../ethsnarks/contracts/MiMC.sol";
+import "../../ethsnarks/contracts/MiMC_hash.sol";
 
 
 contract Miximus
@@ -63,7 +63,9 @@ contract Miximus
 
 
     /**
-    * Returns leaf offset
+    * Inserts a new leaf into the tree upon a deposit of the correct amount
+    *
+    * Returns the index of the new leaf, and the new merkle root for the tree
     */
     function Deposit(uint256 leaf)
         public payable returns (uint256 new_root, uint256 new_offset)
@@ -83,7 +85,7 @@ contract Miximus
     {
         uint256[] memory vals = new uint256[](1);
         vals[0] = secret;
-        return MiMC.Hash(vals);
+        return MiMC_hash.MiMCpe7_mp(vals, 0);
     }
 
 
@@ -132,7 +134,7 @@ contract Miximus
         inputs_to_hash[1] = in_nullifier;
         inputs_to_hash[2] = in_exthash;
 
-        return MiMC.Hash(inputs_to_hash);
+        return MiMC_hash.MiMCpe7_mp(inputs_to_hash, 0);
     }
 
 
@@ -168,6 +170,12 @@ contract Miximus
     )
         public
     {
+        // Clamp inputs to the scalar field
+        // This avoids aliasing, which would allow double spend!
+        uint256 Q = Verifier.ScalarField();
+        in_root = in_root % Q;
+        in_nullifier = in_nullifier % Q;
+
         require( false == nullifiers[in_nullifier], "Cannot double-spend" );
 
         require( true == roots[in_root], "Must specify known merkle tree root" );