diff --git a/src/avalanche/proof.h b/src/avalanche/proof.h
--- a/src/avalanche/proof.h
+++ b/src/avalanche/proof.h
@@ -39,6 +39,11 @@
 
 using StakeId = uint256;
 
+struct StakeCommitment : public uint256 {
+    explicit StakeCommitment() : uint256() {}
+    explicit StakeCommitment(const uint256 &b) : uint256(b) {}
+};
+
 class Stake {
     COutPoint utxo;
 
@@ -69,7 +74,7 @@
     bool isCoinbase() const { return height & 1; }
     const CPubKey &getPubkey() const { return pubkey; }
 
-    uint256 getHash(const ProofId &proofid) const;
+    uint256 getHash(const StakeCommitment &commitment) const;
 
     const StakeId &getId() const { return stakeid; }
 };
@@ -88,7 +93,7 @@
     const Stake &getStake() const { return stake; }
     const SchnorrSig &getSignature() const { return sig; }
 
-    bool verify(const ProofId &proofid) const;
+    bool verify(const StakeCommitment &commitment) const;
 };
 
 class Proof {
@@ -138,6 +143,9 @@
 
     const ProofId &getId() const { return proofid; }
     const LimitedProofId &getLimitedId() const { return limitedProofId; }
+    const StakeCommitment getStakeCommitment() const {
+        return StakeCommitment(proofid);
+    }
     uint32_t getScore() const;
 
     bool verify(ProofValidationState &state) const;
diff --git a/src/avalanche/proof.cpp b/src/avalanche/proof.cpp
--- a/src/avalanche/proof.cpp
+++ b/src/avalanche/proof.cpp
@@ -24,15 +24,15 @@
     stakeid = StakeId(ss.GetHash());
 }
 
-uint256 Stake::getHash(const ProofId &proofid) const {
+uint256 Stake::getHash(const StakeCommitment &commitment) const {
     CHashWriter ss(SER_GETHASH, 0);
-    ss << proofid;
+    ss << commitment;
     ss << *this;
     return ss.GetHash();
 }
 
-bool SignedStake::verify(const ProofId &proofid) const {
-    return stake.getPubkey().VerifySchnorr(stake.getHash(proofid), sig);
+bool SignedStake::verify(const StakeCommitment &commitment) const {
+    return stake.getPubkey().VerifySchnorr(stake.getHash(commitment), sig);
 }
 
 bool Proof::FromHex(Proof &proof, const std::string &hexProof,
@@ -121,7 +121,7 @@
                                  "duplicated-stake");
         }
 
-        if (!ss.verify(proofid)) {
+        if (!ss.verify(getStakeCommitment())) {
             return state.Invalid(
                 ProofValidationResult::INVALID_STAKE_SIGNATURE,
                 "invalid-stake-signature",
diff --git a/src/avalanche/proofbuilder.h b/src/avalanche/proofbuilder.h
--- a/src/avalanche/proofbuilder.h
+++ b/src/avalanche/proofbuilder.h
@@ -27,7 +27,7 @@
         StakeSigner(Stake stake_, CKey key_)
             : stake(std::move(stake_)), key(std::move(key_)) {}
 
-        SignedStake sign(const ProofId &proofid);
+        SignedStake sign(const StakeCommitment &commitment);
     };
 
     struct StakeSignerComparator {
diff --git a/src/avalanche/proofbuilder.cpp b/src/avalanche/proofbuilder.cpp
--- a/src/avalanche/proofbuilder.cpp
+++ b/src/avalanche/proofbuilder.cpp
@@ -8,8 +8,8 @@
 
 namespace avalanche {
 
-SignedStake ProofBuilder::StakeSigner::sign(const ProofId &proofid) {
-    const uint256 h = stake.getHash(proofid);
+SignedStake ProofBuilder::StakeSigner::sign(const StakeCommitment &commitment) {
+    const uint256 h = stake.getHash(commitment);
 
     SchnorrSig sig;
     if (!key.SignSchnorr(h, sig)) {
@@ -34,13 +34,14 @@
 
 Proof ProofBuilder::build() {
     const ProofId proofid = getProofId();
+    const StakeCommitment commitment(proofid);
 
     std::vector<SignedStake> signedStakes;
     signedStakes.reserve(stakes.size());
 
     while (!stakes.empty()) {
         auto handle = stakes.extract(stakes.begin());
-        signedStakes.push_back(handle.value().sign(proofid));
+        signedStakes.push_back(handle.value().sign(commitment));
     }
 
     return Proof(sequence, expirationTime, masterKey.GetPubKey(),
diff --git a/src/avalanche/test/util.cpp b/src/avalanche/test/util.cpp
--- a/src/avalanche/test/util.cpp
+++ b/src/avalanche/test/util.cpp
@@ -66,6 +66,7 @@
 
 Proof TestProofBuilder::buildWithReversedOrderStakes(ProofBuilder &pb) {
     const ProofId proofid = TestProofBuilder::getReverseOrderProofId(pb);
+    const StakeCommitment commitment(proofid);
 
     std::vector<SignedStake> signedStakes;
     signedStakes.reserve(pb.stakes.size());
@@ -74,7 +75,7 @@
         // We need a forward iterator, so pb.stakes.rbegin() is not an
         // option.
         auto handle = pb.stakes.extract(std::prev(pb.stakes.end()));
-        signedStakes.push_back(handle.value().sign(proofid));
+        signedStakes.push_back(handle.value().sign(commitment));
     }
 
     return Proof(pb.sequence, pb.expirationTime, pb.masterKey.GetPubKey(),
@@ -101,13 +102,14 @@
 
 Proof TestProofBuilder::buildDuplicatedStakes(ProofBuilder &pb) {
     const ProofId proofid = TestProofBuilder::getDuplicatedStakeProofId(pb);
+    const StakeCommitment commitment(proofid);
 
     std::vector<SignedStake> signedStakes;
     signedStakes.reserve(2 * pb.stakes.size());
 
     while (!pb.stakes.empty()) {
         auto handle = pb.stakes.extract(pb.stakes.begin());
-        SignedStake signedStake = handle.value().sign(proofid);
+        SignedStake signedStake = handle.value().sign(commitment);
         signedStakes.push_back(signedStake);
         signedStakes.push_back(signedStake);
     }