diff --git a/deposit_contract/contracts/validator_registration.json b/deposit_contract/contracts/validator_registration.json
index cd2004233..12cfd74ac 100644
--- a/deposit_contract/contracts/validator_registration.json
+++ b/deposit_contract/contracts/validator_registration.json
@@ -1 +1 @@
-{"abi": [{"name": "DepositEvent", "inputs": [{"type": "bytes", "name": "pubkey", "indexed": false}, {"type": "bytes", "name": "withdrawal_credentials", "indexed": false}, {"type": "bytes", "name": "amount", "indexed": false}, {"type": "bytes", "name": "signature", "indexed": false}, {"type": "bytes", "name": "index", "indexed": false}], "anonymous": false, "type": "event"}, {"outputs": [], "inputs": [], "constant": false, "payable": false, "type": "constructor"}, {"name": "get_deposit_root", "outputs": [{"type": "bytes32", "name": "out"}], "inputs": [], "constant": true, "payable": false, "type": "function", "gas": 95727}, {"name": "get_deposit_count", "outputs": [{"type": "bytes", "name": "out"}], "inputs": [], "constant": true, "payable": false, "type": "function", "gas": 18283}, {"name": "deposit", "outputs": [], "inputs": [{"type": "bytes", "name": "pubkey"}, {"type": "bytes", "name": "withdrawal_credentials"}, {"type": "bytes", "name": "signature"}, {"type": "bytes32", "name": "deposit_data_root"}], "constant": false, "payable": true, "type": "function", "gas": 1342680}], "bytecode": 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\ No newline at end of file
+{"abi": [{"name": "DepositEvent", "inputs": [{"type": "bytes", "name": "pubkey", "indexed": false}, {"type": "bytes", "name": "withdrawal_credentials", "indexed": false}, {"type": "bytes", "name": "amount", "indexed": false}, {"type": "bytes", "name": "signature", "indexed": false}, {"type": "bytes", "name": "index", "indexed": false}], "anonymous": false, "type": "event"}, {"outputs": [], "inputs": [], "constant": false, "payable": false, "type": "constructor"}, {"name": "get_deposit_root", "outputs": [{"type": "bytes32", "name": "out"}], "inputs": [], "constant": true, "payable": false, "type": "function", "gas": 95628}, {"name": "get_deposit_count", "outputs": [{"type": "bytes", "name": "out"}], "inputs": [], "constant": true, "payable": false, "type": "function", "gas": 18231}, {"name": "deposit", "outputs": [], "inputs": [{"type": "bytes", "name": "pubkey"}, {"type": "bytes", "name": "withdrawal_credentials"}, {"type": "bytes", "name": "signature"}, {"type": "bytes32", "name": "deposit_data_root"}], "constant": false, "payable": true, "type": "function", "gas": 1342274}], "bytecode": 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\ No newline at end of file
diff --git a/deposit_contract/contracts/validator_registration.v.py b/deposit_contract/contracts/validator_registration.v.py
index ca18cbdfd..671252e2e 100644
--- a/deposit_contract/contracts/validator_registration.v.py
+++ b/deposit_contract/contracts/validator_registration.v.py
@@ -1,4 +1,4 @@
-# Vyper target 0.1.0b13
+# Vyper target 0.1.0b13.hotfix1761
 MIN_DEPOSIT_AMOUNT: constant(uint256) = 1000000000  # Gwei
 DEPOSIT_CONTRACT_TREE_DEPTH: constant(uint256) = 32
 MAX_DEPOSIT_COUNT: constant(uint256) = 4294967295 # 2**DEPOSIT_CONTRACT_TREE_DEPTH - 1
diff --git a/deposit_contract/requirements-testing.txt b/deposit_contract/requirements-testing.txt
index 9b07eae6f..fe4b88a23 100644
--- a/deposit_contract/requirements-testing.txt
+++ b/deposit_contract/requirements-testing.txt
@@ -1,5 +1,5 @@
 eth-tester[py-evm]==0.1.0b39
-vyper==0.1.0b13
+https://github.com/vyperlang/vyper/archive/1761-HOTFIX-v0.1.0-beta.13.tar.gz
 web3==5.0.0b2
 pytest==3.6.1
 ../test_libs/pyspec