diff --git a/mina/examples/Airdrop.test.ts b/mina/examples/Airdrop.test.ts
index 8379d9a..253df8a 100644
--- a/mina/examples/Airdrop.test.ts
+++ b/mina/examples/Airdrop.test.ts
@@ -29,7 +29,7 @@ describe('Example Airdrop zkApp', () => {
 
   beforeEach(() => Mina.LocalBlockchain({ proofsEnabled: true })
     .then((local) => {
-      tree = new MerkleTree(17);
+      tree = new MerkleTree(33);
       Mina.setActiveInstance(local);
       app = new Airdrop(appAddr);
       local.addAccount(deployer, "100000000000");
@@ -39,12 +39,11 @@ describe('Example Airdrop zkApp', () => {
   const fundZkApp = () => Mina.transaction(sender, async () => {
     let senderUpdate = AccountUpdate.create(sender);
     senderUpdate.requireSignature();
-    senderUpdate.send({ to: appAddr, amount: UInt64.from(100 * 1e9) });
+    senderUpdate.send({ to: appAddr, amount: 100 * 1e9 });
   }).then((txn) => txn.prove())
     .then((txn) => txn.sign([senderKey]).send());
 
-
-  const deploy = () => Mina.transaction(deployer, async () => {
+  const deploy = () => Mina.transaction(deployer, () => {
     AccountUpdate.fundNewAccount(deployer);
     return app.deploy()
   }).then((txn) => txn.prove())
@@ -70,8 +69,8 @@ describe('Example Airdrop zkApp', () => {
     await deploy();
     await fundZkApp();
 
-    const id1 = 123123123123123n;
-    const truncatedId1 = id1 % 65536n;
+    const id1 = 123123123123123123123123123123n;
+    const truncatedId1 = id1 % (1n << 32n);
     await Mina.transaction(
       sender,
       () => app.claimReward(Field(id1), sigs, new HumanIDWitness(tree.getWitness(truncatedId1)))
@@ -81,8 +80,8 @@ describe('Example Airdrop zkApp', () => {
 
     tree.setLeaf(truncatedId1, Field(1));
 
-    const id2 = 123123123123124n;
-    const truncatedId2 = id2 % 65536n;
+    const id2 = 123123123123123123123123123124n;
+    const truncatedId2 = id2 % (1n << 32n);
     await Mina.transaction(
       sender,
       () => app.claimReward(Field(id2), sigs, new HumanIDWitness(tree.getWitness(truncatedId2)))
@@ -136,7 +135,7 @@ describe('Example Airdrop zkApp', () => {
     )
       .then((txn) => txn.prove())
       .then((txn) => txn.sign([senderKey]).send());
-    
+
     let secondBalance = Mina.getBalance(sender);
 
     expect(secondBalance.sub(firstBalance)).toEqual(UInt64.from(10 * 1e9));
diff --git a/mina/examples/Airdrop.ts b/mina/examples/Airdrop.ts
index b6eceac..465e353 100644
--- a/mina/examples/Airdrop.ts
+++ b/mina/examples/Airdrop.ts
@@ -12,12 +12,12 @@ import {
   acceptHumanIDv1,
 } from "../humanIDv1";
 
+const MINA = 1e9;
+
 /**
  * Example airdrop zkApp, which gives 10 MINA rewards to the first 1000
  * unique humans.
  */
-
-const MINA = 1e9;
 class Airdrop extends SmartContract {
   @state(Field) treeRoot = State<Field>();
 
@@ -32,7 +32,7 @@ class Airdrop extends SmartContract {
     witness: HumanIDWitness,
   ) {
     acceptHumanIDv1(humanIDv1, sigs, this.treeRoot, witness);
-    this.send({ to: this.sender.getAndRequireSignature(), amount: 10 * MINA });
+    this.send({ to: this.sender.getUnconstrained(), amount: 10 * MINA });
   }
 }
 
diff --git a/mina/humanIDv1.ts b/mina/humanIDv1.ts
index 58d038b..24e20f1 100644
--- a/mina/humanIDv1.ts
+++ b/mina/humanIDv1.ts
@@ -6,7 +6,7 @@ class Signatures extends Struct({
   sig3: Signature
 }) { }
 
-class HumanIDWitness extends MerkleWitness(17) { }
+class HumanIDWitness extends MerkleWitness(33) { }
 
 const addToMerkleTree = (treeRoot: State<Field>, witness: HumanIDWitness) => {
   const currentTreeRoot = treeRoot.getAndRequireEquals();
@@ -22,11 +22,11 @@ const authenticate = (humanIDv1: Field, sigs: Signatures) => {
   return true;
 }
 
-const EmptyRoot = Field(0x24807cf0bfd8d61f0f431456489ca762fb4f967c7c58665e80eadd9878b3af19n);
+const EmptyRoot = Field(0x21afce36daa1a2d67391072035f4555a85aea7197e5830b128f121aa382770cdn);
 
 const requireConsistent = (humanIDv1: Field, truncatedHumanIDv1: Field) => {
-  humanIDv1.sub(truncatedHumanIDv1).div(65536).assertLessThan(
-    (1n << 238n) + 0x224698fc094cf91b992d30ed0000n,
+  humanIDv1.sub(truncatedHumanIDv1).div(1n << 32n).assertLessThan(
+    (1n << 222n) + 0x224698fc094cf91b992d30edn,
     "HumanID does not match the witness"
   );
 }