diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 48075c8d4f..67ffb7584e 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -1381,86 +1381,15 @@ When sufficiently many full deposits have been made the deposit contract emits t
 
 ### Vyper code
 
-```python
-## compiled with v0.1.0-beta.6 ##
-
-MIN_DEPOSIT_AMOUNT: constant(uint256) = 1000000000  # Gwei
-MAX_DEPOSIT_AMOUNT: constant(uint256) = 32000000000  # Gwei
-GWEI_PER_ETH: constant(uint256) = 1000000000  # 10**9
-CHAIN_START_FULL_DEPOSIT_THRESHOLD: constant(uint256) = 16384  # 2**14
-DEPOSIT_CONTRACT_TREE_DEPTH: constant(uint256) = 32
-TWO_TO_POWER_OF_TREE_DEPTH: constant(uint256) = 4294967296  # 2**32
-SECONDS_PER_DAY: constant(uint256) = 86400
-
-Deposit: event({deposit_root: bytes32, data: bytes[528], merkle_tree_index: bytes[8], branch: bytes32[32]})
-ChainStart: event({deposit_root: bytes32, time: bytes[8]})
-
-zerohashes: bytes32[32]
-branch: bytes32[32]
-deposit_count: uint256
-full_deposit_count: uint256
-chainStarted: public(bool)
-
-@public
-def __init__():
-    for i in range(31):
-        self.zerohashes[i+1] = sha3(concat(self.zerohashes[i], self.zerohashes[i]))
-        self.branch[i+1] = self.zerohashes[i+1]
-
-@public
-@constant
-def get_deposit_root() -> bytes32:
-    root:bytes32 = 0x0000000000000000000000000000000000000000000000000000000000000000
-    size:uint256 = self.deposit_count
-    for h in range(32):
-        if size % 2 == 1:
-            root = sha3(concat(self.branch[h], root))
-        else:
-            root = sha3(concat(root, self.zerohashes[h]))
-        size /= 2
-    return root
-
-@payable
-@public
-def deposit(deposit_input: bytes[512]):
-    assert msg.value >= as_wei_value(MIN_DEPOSIT_AMOUNT, "gwei")
-    assert msg.value <= as_wei_value(MAX_DEPOSIT_AMOUNT, "gwei")
-
-    index: uint256 = self.deposit_count
-    deposit_amount: bytes[8] = slice(concat("", convert(msg.value / GWEI_PER_ETH, bytes32)), start=24, len=8)
-    deposit_timestamp: bytes[8] = slice(concat("", convert(block.timestamp, bytes32)), start=24, len=8)
-    deposit_data: bytes[528] = concat(deposit_amount, deposit_timestamp, deposit_input)
-    merkle_tree_index: bytes[8] = slice(concat("", convert(index, bytes32)), start=24, len=8)
-
-    # add deposit to merkle tree
-    i: int128 = 0
-    power_of_two: uint256 = 2
-    for _ in range(32):
-        if (index+1) % power_of_two != 0:
-            break
-        i += 1
-        power_of_two *= 2
-    value:bytes32 = sha3(deposit_data)
-    for j in range(32):
-        if j < i:
-            value = sha3(concat(self.branch[j], value))
-    self.branch[i] = value
-
-    self.deposit_count += 1
+The source for the Vyper contract lives in a [separate repository](https://github.com/ethereum/deposit_contract) at [https://github.com/ethereum/deposit_contract/blob/master/deposit_contract/contracts/validator_registration.v.py](https://github.com/ethereum/deposit_contract/blob/master/deposit_contract/contracts/validator_registration.v.py).
 
-    new_deposit_root:bytes32 = self.get_deposit_root()
-    log.Deposit(new_deposit_root, deposit_data, merkle_tree_index, self.branch)
+Note: to save ~10x on gas this contract uses a somewhat unintuitive progressive Merkle root calculation algo that requires only O(log(n)) storage. See https://github.com/ethereum/research/blob/master/beacon_chain_impl/progressive_merkle_tree.py for an implementation of the same algo in python tested for correctness.
 
-    if msg.value == as_wei_value(MAX_DEPOSIT_AMOUNT, "gwei"):
-        self.full_deposit_count += 1
-        if self.full_deposit_count == CHAIN_START_FULL_DEPOSIT_THRESHOLD:
-            timestamp_day_boundary: uint256 = as_unitless_number(block.timestamp) - as_unitless_number(block.timestamp) % SECONDS_PER_DAY + SECONDS_PER_DAY
-            chainstart_time: bytes[8] = slice(concat("", convert(timestamp_day_boundary, bytes32)), start=24, len=8)
-            log.ChainStart(new_deposit_root, chainstart_time)
-            self.chainStarted = True
-```
+For convenience, we provide the interface to the contract here:
 
-Note: to save ~10x on gas this contract uses a somewhat unintuitive progressive Merkle root calculation algo that requires only O(log(n)) storage. See https://github.com/ethereum/research/blob/master/beacon_chain_impl/progressive_merkle_tree.py for an implementation of the same algo in python tested for correctness.
+* `__init__()`: initializes the contract
+* `get_deposit_root() -> bytes32`: returns the current root of the deposit tree
+* `deposit(bytes[512])`: adds a deposit instance to the deposit tree, incorporating the input argument and the value transferred in the given call. Note: the amount of value transferred *must* be within `MIN_DEPOSIT_AMOUNT` and `MAX_DEPOSIT_AMOUNT`, inclusive. Each of these constants are specified in units of Gwei.
 
 ## On startup