From cda10d059b61bc610493509803120e92c1bdf85b Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Wed, 27 Mar 2024 16:49:12 +0600
Subject: [PATCH 01/25] Refactor EL withdraw request processing

---
 specs/_features/eip7251/beacon-chain.md | 29 +++++++++++++++++--------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index c4aad0a6f..19fb7a91d 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -8,6 +8,7 @@
 
 - [Introduction](#introduction)
 - [Constants](#constants)
+  - [Misc](#misc)
   - [Withdrawal prefixes](#withdrawal-prefixes)
   - [Domains](#domains)
 - [Presets](#presets)
@@ -87,6 +88,12 @@ See [a modest proposal](https://notes.ethereum.org/@mikeneuder/increase-maxeb),
 
 The following values are (non-configurable) constants used throughout the specification.
 
+### Misc
+
+| Name | Value |
+| - | - |
+| `FULL_EXIT_REQUEST_AMOUNT` | `uint64(2**64 - 1)` |
+
 ### Withdrawal prefixes
 
 | Name | Value |
@@ -866,7 +873,8 @@ def process_execution_layer_withdraw_request(
     execution_layer_withdraw_request: ExecutionLayerWithdrawRequest
 ) -> None:
     amount = execution_layer_withdraw_request.amount
-    is_full_exit_request = amount == 0
+    is_full_exit_request = amount == FULL_EXIT_REQUEST_AMOUNT
+
     # If partial withdrawal queue is full, only full exits are processed 
     if len(state.pending_partial_withdrawals) >= PENDING_PARTIAL_WITHDRAWALS_LIMIT and not is_full_exit_request:
         return
@@ -888,20 +896,23 @@ def process_execution_layer_withdraw_request(
         and get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
     ):
         return
-    # New condition: only allow partial withdrawals with compounding withdrawal credentials
-    if not (is_full_exit_request or has_compounding_withdrawal_credential(validator)):
-        return
 
     pending_balance_to_withdraw = sum(
         item.amount for item in state.pending_partial_withdrawals if item.index == index
     )
-    # only exit validator if it has no pending withdrawals in the queue
-    if is_full_exit_request and pending_balance_to_withdraw > 0:
-        return
 
     if is_full_exit_request:
-        initiate_validator_exit(state, index)
-    elif state.balances[index] > MIN_ACTIVATION_BALANCE + pending_balance_to_withdraw:
+        # Only exit validator if it has no pending withdrawals in the queue
+        if pending_balance_to_withdraw == 0:
+            initiate_validator_exit(state, index)
+
+        return
+
+
+    has_excess_balance = state.balances[index] > MIN_ACTIVATION_BALANCE + pending_balance_to_withdraw
+
+    # Only allow partial withdrawals with compounding withdrawal credentials
+    if has_compounding_withdrawal_credential(validator) and has_excess_balance:
         to_withdraw = min(
             state.balances[index] - MIN_ACTIVATION_BALANCE - pending_balance_to_withdraw,
             amount

From 6f5cc4baf5e6b8cb9b753085fb9738c540147b8a Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Wed, 27 Mar 2024 17:35:27 +0600
Subject: [PATCH 02/25] Replace MIN_ACTIVATION_BALANCE with
 MAX_EFFECTIVE_BALANCE

---
 specs/_features/eip7251/beacon-chain.md | 28 +++++++++----------------
 1 file changed, 10 insertions(+), 18 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 19fb7a91d..b7c2ffdb1 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -373,7 +373,7 @@ def get_validator_max_effective_balance(validator: Validator) -> Gwei:
     if has_compounding_withdrawal_credential(validator):
         return MAX_EFFECTIVE_BALANCE_EIP7251
     else:
-        return MIN_ACTIVATION_BALANCE
+        return MAX_EFFECTIVE_BALANCE
 ```
 
 #### New `get_churn_limit`
@@ -411,12 +411,8 @@ def get_consolidation_churn_limit(state: BeaconState) -> Gwei:
 
 ```python
 def get_active_balance(state: BeaconState, validator_index: ValidatorIndex) -> Gwei:
-    active_balance_ceil = (
-        MIN_ACTIVATION_BALANCE 
-        if has_eth1_withdrawal_credential(state.validators[validator_index]) 
-        else MAX_EFFECTIVE_BALANCE_EIP7251
-    )
-    return min(state.balances[validator_index], active_balance_ceil)
+    max_effective_balance = get_validator_max_effective_balance(state.validators[validator_index])
+    return min(state.balances[validator_index], max_effective_balance)
 ```
 
 ### Beacon state mutators
@@ -649,16 +645,12 @@ def process_effective_balance_updates(state: BeaconState) -> None:
         HYSTERESIS_INCREMENT = uint64(EFFECTIVE_BALANCE_INCREMENT // HYSTERESIS_QUOTIENT)
         DOWNWARD_THRESHOLD = HYSTERESIS_INCREMENT * HYSTERESIS_DOWNWARD_MULTIPLIER
         UPWARD_THRESHOLD = HYSTERESIS_INCREMENT * HYSTERESIS_UPWARD_MULTIPLIER
-        EFFECTIVE_BALANCE_LIMIT = (
-            MAX_EFFECTIVE_BALANCE_EIP7251 if has_compounding_withdrawal_credential(validator)
-            else MIN_ACTIVATION_BALANCE
-        )
-
+        max_effective_balance = get_validator_max_effective_balance(validator)
         if (
             balance + DOWNWARD_THRESHOLD < validator.effective_balance
             or validator.effective_balance + UPWARD_THRESHOLD < balance
         ):
-            validator.effective_balance = min(balance - balance % EFFECTIVE_BALANCE_INCREMENT, EFFECTIVE_BALANCE_LIMIT)
+            validator.effective_balance = min(balance - balance % EFFECTIVE_BALANCE_INCREMENT, max_effective_balance)  # [Modified in EIP7251]
 ```
 
 ### Block processing
@@ -689,8 +681,8 @@ def get_expected_withdrawals(state: BeaconState) -> Tuple[Sequence[Withdrawal],
             break
 
         validator = state.validators[withdrawal.index]
-        if validator.exit_epoch == FAR_FUTURE_EPOCH and state.balances[withdrawal.index] > MIN_ACTIVATION_BALANCE:
-            withdrawable_balance = min(state.balances[withdrawal.index] - MIN_ACTIVATION_BALANCE, withdrawal.amount)
+        if validator.exit_epoch == FAR_FUTURE_EPOCH and state.balances[withdrawal.index] > MAX_EFFECTIVE_BALANCE:
+            withdrawable_balance = min(state.balances[withdrawal.index] - MAX_EFFECTIVE_BALANCE, withdrawal.amount)
             withdrawals.append(Withdrawal(
                 index=withdrawal_index,
                 validator_index=withdrawal.index,
@@ -909,12 +901,12 @@ def process_execution_layer_withdraw_request(
         return
 
 
-    has_excess_balance = state.balances[index] > MIN_ACTIVATION_BALANCE + pending_balance_to_withdraw
+    has_excess_balance = state.balances[index] > MAX_EFFECTIVE_BALANCE + pending_balance_to_withdraw
 
     # Only allow partial withdrawals with compounding withdrawal credentials
     if has_compounding_withdrawal_credential(validator) and has_excess_balance:
         to_withdraw = min(
-            state.balances[index] - MIN_ACTIVATION_BALANCE - pending_balance_to_withdraw,
+            state.balances[index] - MAX_EFFECTIVE_BALANCE - pending_balance_to_withdraw,
             amount
         )
         exit_queue_epoch = compute_exit_epoch_and_update_churn(state, to_withdraw)
@@ -935,7 +927,7 @@ def process_consolidation(state: BeaconState, signed_consolidation: SignedConsol
     # If the pending consolidations queue is full, no consolidations are allowed in the block
     assert len(state.pending_consolidations) < PENDING_CONSOLIDATIONS_LIMIT
     # If there is too little available consolidation churn limit, no consolidations are allowed in the block
-    assert get_consolidation_churn_limit(state) > MIN_ACTIVATION_BALANCE
+    assert get_consolidation_churn_limit(state) > MAX_EFFECTIVE_BALANCE
     consolidation = signed_consolidation.message
     # Verify that source != target, so a consolidation cannot be used as an exit.
     assert consolidation.source_index != consolidation.target_index

From 31142b0ba18572c888618bd8ef87deb1dd96bc92 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Wed, 27 Mar 2024 17:41:00 +0600
Subject: [PATCH 03/25] Require sufficient EB to emit partial withdrawal

---
 specs/_features/eip7251/beacon-chain.md | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index b7c2ffdb1..2035180af 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -681,7 +681,9 @@ def get_expected_withdrawals(state: BeaconState) -> Tuple[Sequence[Withdrawal],
             break
 
         validator = state.validators[withdrawal.index]
-        if validator.exit_epoch == FAR_FUTURE_EPOCH and state.balances[withdrawal.index] > MAX_EFFECTIVE_BALANCE:
+        has_sufficient_effective_balance = validator.effective_balance == MAX_EFFECTIVE_BALANCE
+        has_excess_balance = state.balances[withdrawal.index] > MAX_EFFECTIVE_BALANCE
+        if validator.exit_epoch == FAR_FUTURE_EPOCH and has_sufficient_effective_balance and has_excess_balance:
             withdrawable_balance = min(state.balances[withdrawal.index] - MAX_EFFECTIVE_BALANCE, withdrawal.amount)
             withdrawals.append(Withdrawal(
                 index=withdrawal_index,
@@ -901,10 +903,11 @@ def process_execution_layer_withdraw_request(
         return
 
 
+    has_sufficient_effective_balance = validator.effective_balance == MAX_EFFECTIVE_BALANCE
     has_excess_balance = state.balances[index] > MAX_EFFECTIVE_BALANCE + pending_balance_to_withdraw
 
     # Only allow partial withdrawals with compounding withdrawal credentials
-    if has_compounding_withdrawal_credential(validator) and has_excess_balance:
+    if has_compounding_withdrawal_credential(validator) and has_sufficient_effective_balance and has_excess_balance:
         to_withdraw = min(
             state.balances[index] - MAX_EFFECTIVE_BALANCE - pending_balance_to_withdraw,
             amount

From 46638d31baf38b5d2b8178b7b51343822438b548 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Wed, 27 Mar 2024 17:42:10 +0600
Subject: [PATCH 04/25] Remove unused method

---
 specs/_features/eip7251/beacon-chain.md | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 2035180af..e8c4e8a51 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -46,7 +46,6 @@
     - [New `get_active_balance`](#new-get_active_balance)
   - [Beacon state mutators](#beacon-state-mutators)
     - [Updated  `initiate_validator_exit`](#updated--initiate_validator_exit)
-    - [New `set_compounding_withdrawal_credentials`](#new-set_compounding_withdrawal_credentials)
     - [New `switch_to_compounding_validator`](#new-switch_to_compounding_validator)
     - [New `queue_excess_active_balance`](#new-queue_excess_active_balance)
     - [New `compute_exit_epoch_and_update_churn`](#new-compute_exit_epoch_and_update_churn)
@@ -437,15 +436,6 @@ def initiate_validator_exit(state: BeaconState, index: ValidatorIndex) -> None:
     validator.withdrawable_epoch = Epoch(validator.exit_epoch + MIN_VALIDATOR_WITHDRAWABILITY_DELAY)
 ```
 
-#### New `set_compounding_withdrawal_credentials`
-
-```python
-def set_compounding_withdrawal_credentials(state: BeaconState, index: ValidatorIndex) -> None:
-    validator = state.validators[index]
-    if has_eth1_withdrawal_credential(validator):
-        validator.withdrawal_credentials[:1] = COMPOUNDING_WITHDRAWAL_PREFIX
-```
-
 #### New `switch_to_compounding_validator`
 
 ```python

From 517f741f29a53ff8068283dc5ac8f694b5d5cc58 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Wed, 27 Mar 2024 17:57:54 +0600
Subject: [PATCH 05/25] Abort voluntary exit if validator has pending partial
 withdrawals

---
 specs/_features/eip7251/beacon-chain.md | 42 ++++++++++++++++++++++---
 1 file changed, 38 insertions(+), 4 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index e8c4e8a51..3bd461566 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -44,6 +44,7 @@
     - [New `get_activation_exit_churn_limit`](#new-get_activation_exit_churn_limit)
     - [New `get_consolidation_churn_limit`](#new-get_consolidation_churn_limit)
     - [New `get_active_balance`](#new-get_active_balance)
+    - [New `get_pending_balance_to_withdraw`](#new-get_pending_balance_to_withdraw)
   - [Beacon state mutators](#beacon-state-mutators)
     - [Updated  `initiate_validator_exit`](#updated--initiate_validator_exit)
     - [New `switch_to_compounding_validator`](#new-switch_to_compounding_validator)
@@ -72,6 +73,8 @@
         - [New `process_execution_layer_withdraw_request`](#new-process_execution_layer_withdraw_request)
       - [Consolidations](#consolidations)
         - [New `process_consolidation`](#new-process_consolidation)
+      - [Voluntary exits](#voluntary-exits)
+        - [Updated `process_voluntary_exit`](#updated-process_voluntary_exit)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 <!-- /TOC -->
@@ -414,6 +417,14 @@ def get_active_balance(state: BeaconState, validator_index: ValidatorIndex) -> G
     return min(state.balances[validator_index], max_effective_balance)
 ```
 
+#### New `get_pending_balance_to_withdraw`
+
+```python
+def get_pending_balance_to_withdraw(state: BeaconState, validator_index: ValidatorIndex) -> Gwei:
+    return sum(
+        withdrawal.amount for withdrawal in state.pending_partial_withdrawals if withdrawal.index == validator_index)
+```
+
 ### Beacon state mutators
 
 #### Updated  `initiate_validator_exit`
@@ -762,7 +773,7 @@ def process_operations(state: BeaconState, body: BeaconBlockBody) -> None:
     for_ops(body.attester_slashings, process_attester_slashing)
     for_ops(body.attestations, process_attestation)
     for_ops(body.deposits, process_deposit)  # [Modified in EIP7251]
-    for_ops(body.voluntary_exits, process_voluntary_exit)
+    for_ops(body.voluntary_exits, process_voluntary_exit)  # [Modified in EIP7251]
     for_ops(body.bls_to_execution_changes, process_bls_to_execution_change)
     for_ops(body.execution_payload.withdraw_requests, process_execution_layer_withdraw_request)  # New in EIP7251
     for_ops(body.consolidations, process_consolidation)  # New in EIP7251
@@ -881,9 +892,7 @@ def process_execution_layer_withdraw_request(
     ):
         return
 
-    pending_balance_to_withdraw = sum(
-        item.amount for item in state.pending_partial_withdrawals if item.index == index
-    )
+    pending_balance_to_withdraw = get_pending_balance_to_withdraw(state, index)
 
     if is_full_exit_request:
         # Only exit validator if it has no pending withdrawals in the queue
@@ -961,3 +970,28 @@ def process_consolidation(state: BeaconState, signed_consolidation: SignedConsol
     ))
 ```
 
+##### Voluntary exits
+
+###### Updated `process_voluntary_exit`
+
+```python
+def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVoluntaryExit) -> None:
+    voluntary_exit = signed_voluntary_exit.message
+    validator = state.validators[voluntary_exit.validator_index]
+    # Verify the validator is active
+    assert is_active_validator(validator, get_current_epoch(state))
+    # Verify exit has not been initiated
+    assert validator.exit_epoch == FAR_FUTURE_EPOCH
+    # Exits must specify an epoch when they become valid; they are not valid before then
+    assert get_current_epoch(state) >= voluntary_exit.epoch
+    # Verify the validator has been active long enough
+    assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
+    # Verify signature
+    domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
+    signing_root = compute_signing_root(voluntary_exit, domain)
+    assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
+    # Only exit validator if it has no pending withdrawals in the queue
+    assert get_pending_balance_to_withdraw(state, voluntary_exit.validator_index) == 0  # [New in EIP7251]
+    # Initiate exit
+    initiate_validator_exit(state, voluntary_exit.validator_index)
+```
\ No newline at end of file

From 915f90e13eddf4ddfcc38b3b1b3d89a91d10b86c Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Wed, 27 Mar 2024 18:05:05 +0600
Subject: [PATCH 06/25] Strictly check withdrawal address upon consolidation

---
 specs/_features/eip7251/beacon-chain.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 3bd461566..366eabe4c 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -950,7 +950,7 @@ def process_consolidation(state: BeaconState, signed_consolidation: SignedConsol
     assert has_execution_withdrawal_credential(source_validator)
     assert has_execution_withdrawal_credential(target_validator)
     # Verify the same withdrawal address
-    assert source_validator.withdrawal_credentials[1:] == target_validator.withdrawal_credentials[1:]
+    assert source_validator.withdrawal_credentials[12:] == target_validator.withdrawal_credentials[12:]
 
     # Verify consolidation is signed by the source and the target
     domain = compute_domain(DOMAIN_CONSOLIDATION, genesis_validators_root=state.genesis_validators_root)

From 534bcfc116980efe92a032115f883e79d4825393 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Thu, 28 Mar 2024 11:49:44 +0600
Subject: [PATCH 07/25] Use source.effective_balance for consolidaiton churn

---
 specs/_features/eip7251/beacon-chain.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 366eabe4c..a0bc3bc8d 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -959,8 +959,8 @@ def process_consolidation(state: BeaconState, signed_consolidation: SignedConsol
     assert bls.FastAggregateVerify(pubkeys, signing_root, signed_consolidation.signature)
 
     # Initiate source validator exit and append pending consolidation
-    active_balance = get_active_balance(state, consolidation.source_index)
-    source_validator.exit_epoch = compute_consolidation_epoch_and_update_churn(state, active_balance)
+    source_validator.exit_epoch = compute_consolidation_epoch_and_update_churn(
+        state, source_validator.effective_balance)
     source_validator.withdrawable_epoch = Epoch(
         source_validator.exit_epoch + MIN_VALIDATOR_WITHDRAWABILITY_DELAY
     )

From 7bbecfb7625ce1411d4cf902a9dc54be0f76165d Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Fri, 29 Mar 2024 15:27:12 +0600
Subject: [PATCH 08/25] Revert "Replace MIN_ACTIVATION_BALANCE with
 MAX_EFFECTIVE_BALANCE"

This reverts commit 6f5cc4baf5e6b8cb9b753085fb9738c540147b8a.
---
 specs/_features/eip7251/beacon-chain.md | 32 +++++++++++++++----------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index a0bc3bc8d..db6d7601a 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -375,7 +375,7 @@ def get_validator_max_effective_balance(validator: Validator) -> Gwei:
     if has_compounding_withdrawal_credential(validator):
         return MAX_EFFECTIVE_BALANCE_EIP7251
     else:
-        return MAX_EFFECTIVE_BALANCE
+        return MIN_ACTIVATION_BALANCE
 ```
 
 #### New `get_churn_limit`
@@ -413,8 +413,12 @@ def get_consolidation_churn_limit(state: BeaconState) -> Gwei:
 
 ```python
 def get_active_balance(state: BeaconState, validator_index: ValidatorIndex) -> Gwei:
-    max_effective_balance = get_validator_max_effective_balance(state.validators[validator_index])
-    return min(state.balances[validator_index], max_effective_balance)
+    active_balance_ceil = (
+        MIN_ACTIVATION_BALANCE 
+        if has_eth1_withdrawal_credential(state.validators[validator_index]) 
+        else MAX_EFFECTIVE_BALANCE_EIP7251
+    )
+    return min(state.balances[validator_index], active_balance_ceil)
 ```
 
 #### New `get_pending_balance_to_withdraw`
@@ -646,12 +650,16 @@ def process_effective_balance_updates(state: BeaconState) -> None:
         HYSTERESIS_INCREMENT = uint64(EFFECTIVE_BALANCE_INCREMENT // HYSTERESIS_QUOTIENT)
         DOWNWARD_THRESHOLD = HYSTERESIS_INCREMENT * HYSTERESIS_DOWNWARD_MULTIPLIER
         UPWARD_THRESHOLD = HYSTERESIS_INCREMENT * HYSTERESIS_UPWARD_MULTIPLIER
-        max_effective_balance = get_validator_max_effective_balance(validator)
+        EFFECTIVE_BALANCE_LIMIT = (
+            MAX_EFFECTIVE_BALANCE_EIP7251 if has_compounding_withdrawal_credential(validator)
+            else MIN_ACTIVATION_BALANCE
+        )
+
         if (
             balance + DOWNWARD_THRESHOLD < validator.effective_balance
             or validator.effective_balance + UPWARD_THRESHOLD < balance
         ):
-            validator.effective_balance = min(balance - balance % EFFECTIVE_BALANCE_INCREMENT, max_effective_balance)  # [Modified in EIP7251]
+            validator.effective_balance = min(balance - balance % EFFECTIVE_BALANCE_INCREMENT, EFFECTIVE_BALANCE_LIMIT)
 ```
 
 ### Block processing
@@ -682,10 +690,10 @@ def get_expected_withdrawals(state: BeaconState) -> Tuple[Sequence[Withdrawal],
             break
 
         validator = state.validators[withdrawal.index]
-        has_sufficient_effective_balance = validator.effective_balance == MAX_EFFECTIVE_BALANCE
-        has_excess_balance = state.balances[withdrawal.index] > MAX_EFFECTIVE_BALANCE
+        has_sufficient_effective_balance = validator.effective_balance == MIN_ACTIVATION_BALANCE
+        has_excess_balance = state.balances[withdrawal.index] > MIN_ACTIVATION_BALANCE
         if validator.exit_epoch == FAR_FUTURE_EPOCH and has_sufficient_effective_balance and has_excess_balance:
-            withdrawable_balance = min(state.balances[withdrawal.index] - MAX_EFFECTIVE_BALANCE, withdrawal.amount)
+            withdrawable_balance = min(state.balances[withdrawal.index] - MIN_ACTIVATION_BALANCE, withdrawal.amount)
             withdrawals.append(Withdrawal(
                 index=withdrawal_index,
                 validator_index=withdrawal.index,
@@ -902,13 +910,13 @@ def process_execution_layer_withdraw_request(
         return
 
 
-    has_sufficient_effective_balance = validator.effective_balance == MAX_EFFECTIVE_BALANCE
-    has_excess_balance = state.balances[index] > MAX_EFFECTIVE_BALANCE + pending_balance_to_withdraw
+    has_sufficient_effective_balance = validator.effective_balance == MIN_ACTIVATION_BALANCE
+    has_excess_balance = state.balances[index] > MIN_ACTIVATION_BALANCE + pending_balance_to_withdraw
 
     # Only allow partial withdrawals with compounding withdrawal credentials
     if has_compounding_withdrawal_credential(validator) and has_sufficient_effective_balance and has_excess_balance:
         to_withdraw = min(
-            state.balances[index] - MAX_EFFECTIVE_BALANCE - pending_balance_to_withdraw,
+            state.balances[index] - MIN_ACTIVATION_BALANCE - pending_balance_to_withdraw,
             amount
         )
         exit_queue_epoch = compute_exit_epoch_and_update_churn(state, to_withdraw)
@@ -929,7 +937,7 @@ def process_consolidation(state: BeaconState, signed_consolidation: SignedConsol
     # If the pending consolidations queue is full, no consolidations are allowed in the block
     assert len(state.pending_consolidations) < PENDING_CONSOLIDATIONS_LIMIT
     # If there is too little available consolidation churn limit, no consolidations are allowed in the block
-    assert get_consolidation_churn_limit(state) > MAX_EFFECTIVE_BALANCE
+    assert get_consolidation_churn_limit(state) > MIN_ACTIVATION_BALANCE
     consolidation = signed_consolidation.message
     # Verify that source != target, so a consolidation cannot be used as an exit.
     assert consolidation.source_index != consolidation.target_index

From 221f273e14aff0356d1b98ac1920dcc7dd523765 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Fri, 29 Mar 2024 22:35:12 +0600
Subject: [PATCH 09/25] Fix lint

---
 specs/_features/eip7251/beacon-chain.md | 1 -
 1 file changed, 1 deletion(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index db6d7601a..845ff1b96 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -909,7 +909,6 @@ def process_execution_layer_withdraw_request(
 
         return
 
-
     has_sufficient_effective_balance = validator.effective_balance == MIN_ACTIVATION_BALANCE
     has_excess_balance = state.balances[index] > MIN_ACTIVATION_BALANCE + pending_balance_to_withdraw
 

From 04ef1181a8b9da5c7e3fc9aa51ba632eb09d21a3 Mon Sep 17 00:00:00 2001
From: Lion - dapplion <35266934+dapplion@users.noreply.github.com>
Date: Wed, 3 Apr 2024 08:31:43 +0900
Subject: [PATCH 10/25] Remove repetitive word

---
 .../phase0/epoch_processing/test_process_registry_updates.py    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/core/pyspec/eth2spec/test/phase0/epoch_processing/test_process_registry_updates.py b/tests/core/pyspec/eth2spec/test/phase0/epoch_processing/test_process_registry_updates.py
index b7a7be76a..3cb73086c 100644
--- a/tests/core/pyspec/eth2spec/test/phase0/epoch_processing/test_process_registry_updates.py
+++ b/tests/core/pyspec/eth2spec/test/phase0/epoch_processing/test_process_registry_updates.py
@@ -114,7 +114,7 @@ def test_activation_queue_sorting(spec, state):
     assert state.validators[mock_activations - 2].activation_epoch == spec.FAR_FUTURE_EPOCH
     # the one at churn_limit did not make it, it was out-prioritized
     assert state.validators[churn_limit].activation_epoch == spec.FAR_FUTURE_EPOCH
-    # but the the one in front of the above did
+    # but the one in front of the above did
     assert state.validators[churn_limit - 1].activation_epoch != spec.FAR_FUTURE_EPOCH
 
 

From a12e16b739b8abbc3cffaaed64fc528e0bce2a09 Mon Sep 17 00:00:00 2001
From: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
Date: Thu, 4 Apr 2024 17:01:08 +0900
Subject: [PATCH 11/25] Add EIP-7549 aggregation logic to testing tools

---
 .../test_should_override_forkchoice_update.py |   6 +-
 .../eth2spec/test/helpers/attestations.py     | 121 ++++++++++++------
 .../fork_choice/test_get_proposer_head.py     |   6 +-
 .../test/phase0/fork_choice/test_reorg.py     |   8 +-
 4 files changed, 95 insertions(+), 46 deletions(-)

diff --git a/tests/core/pyspec/eth2spec/test/bellatrix/fork_choice/test_should_override_forkchoice_update.py b/tests/core/pyspec/eth2spec/test/bellatrix/fork_choice/test_should_override_forkchoice_update.py
index b40cc5bbe..6c8e33e95 100644
--- a/tests/core/pyspec/eth2spec/test/bellatrix/fork_choice/test_should_override_forkchoice_update.py
+++ b/tests/core/pyspec/eth2spec/test/bellatrix/fork_choice/test_should_override_forkchoice_update.py
@@ -7,7 +7,7 @@ from eth2spec.test.helpers.constants import (
     MINIMAL,
 )
 from eth2spec.test.helpers.attestations import (
-    get_valid_attestation_at_slot,
+    get_valid_attestations_at_slot,
 )
 from eth2spec.test.helpers.block import (
     build_empty_block_for_next_slot,
@@ -109,7 +109,7 @@ def test_should_override_forkchoice_update__true(spec, state):
     # Fill a slot with attestations to its parent
     block = build_empty_block_for_next_slot(spec, state)
     parent_block_slot = block.slot - 1
-    block.body.attestations = get_valid_attestation_at_slot(
+    block.body.attestations = get_valid_attestations_at_slot(
         state,
         spec,
         parent_block_slot,
@@ -135,7 +135,7 @@ def test_should_override_forkchoice_update__true(spec, state):
     # Add attestations to the parent block
     temp_state = state.copy()
     next_slot(spec, temp_state)
-    attestations = get_valid_attestation_at_slot(
+    attestations = get_valid_attestations_at_slot(
         temp_state,
         spec,
         slot_to_attest=temp_state.slot - 1,
diff --git a/tests/core/pyspec/eth2spec/test/helpers/attestations.py b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
index 528de7f67..e57eb8318 100644
--- a/tests/core/pyspec/eth2spec/test/helpers/attestations.py
+++ b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
@@ -84,7 +84,6 @@ def build_attestation_data(spec, state, slot, index, beacon_block_root=None, sha
         target=spec.Checkpoint(epoch=spec.compute_epoch_at_slot(slot), root=epoch_boundary_root),
     )
 
-    # if spec.fork == SHARDING  # TODO: add extra data for shard voting
     return data
 
 
@@ -95,8 +94,12 @@ def get_valid_attestation(spec,
                           filter_participant_set=None,
                           beacon_block_root=None,
                           signed=False):
-    # If filter_participant_set filters everything, the attestation has 0 participants, and cannot be signed.
-    # Thus strictly speaking invalid when no participant is added later.
+    """
+    Return a valid attestation at `slot` and committee index `index`.
+
+    If filter_participant_set filters everything, the attestation has 0 participants, and cannot be signed.
+    Thus strictly speaking invalid when no participant is added later.
+    """
     if slot is None:
         slot = state.slot
     if index is None:
@@ -104,18 +107,8 @@ def get_valid_attestation(spec,
 
     attestation_data = build_attestation_data(spec, state, slot=slot, index=index, beacon_block_root=beacon_block_root)
 
-    beacon_committee = spec.get_beacon_committee(state, slot, index)
+    attestation = spec.Attestation(data=attestation_data)
 
-    if is_post_eip7549(spec):
-        # will fill aggregation_bits later
-        attestation = spec.Attestation(data=attestation_data)
-    else:
-        committee_size = len(beacon_committee)
-        aggregation_bits = Bitlist[spec.MAX_VALIDATORS_PER_COMMITTEE](*([0] * committee_size))
-        attestation = spec.Attestation(
-            aggregation_bits=aggregation_bits,
-            data=attestation_data,
-        )
     # fill the attestation with (optionally filtered) participants, and optionally sign it
     fill_aggregate_attestation(spec, state, attestation, signed=signed,
                                filter_participant_set=filter_participant_set, committee_index=index)
@@ -132,7 +125,7 @@ def sign_aggregate_attestation(spec, state, attestation_data, participants: List
                 spec,
                 state,
                 attestation_data,
-                privkey
+                privkey,
             )
         )
     return bls.Aggregate(signatures)
@@ -180,11 +173,16 @@ def fill_aggregate_attestation(spec, state, attestation, committee_index, signed
     if filter_participant_set is not None:
         participants = filter_participant_set(participants)
 
+    # initialize `aggregation_bits`
     if is_post_eip7549(spec):
-        attestation.committee_bits = spec.Bitvector[spec.MAX_COMMITTEES_PER_SLOT]()
         attestation.committee_bits[committee_index] = True
         attestation.aggregation_bits = get_empty_eip7549_aggregation_bits(
             spec, state, attestation.committee_bits, attestation.data.slot)
+    else:
+        committee_size = len(beacon_committee)
+        attestation.aggregation_bits = Bitlist[spec.MAX_VALIDATORS_PER_COMMITTEE](*([0] * committee_size))
+
+    # fill in the `aggregation_bits`
     for i in range(len(beacon_committee)):
         if is_post_eip7549(spec):
             offset = get_eip7549_aggregation_bits_offset(
@@ -205,7 +203,10 @@ def add_attestations_to_state(spec, state, attestations, slot):
         spec.process_attestation(state, attestation)
 
 
-def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=None, beacon_block_root=None):
+def get_valid_attestations_at_slot(state, spec, slot_to_attest, participation_fn=None, beacon_block_root=None):
+    """
+    Return attestations at slot `slot_to_attest`.
+    """
     committees_per_slot = spec.get_committee_count_per_slot(state, spec.compute_epoch_at_slot(slot_to_attest))
     for index in range(committees_per_slot):
         def participants_filter(comm):
@@ -213,7 +214,6 @@ def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=
                 return comm
             else:
                 return participation_fn(state.slot, index, comm)
-        # if spec.fork == SHARDING:  TODO: add shard data to attestation, include shard headers in block
         yield get_valid_attestation(
             spec,
             state,
@@ -225,6 +225,48 @@ def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=
         )
 
 
+def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=None, beacon_block_root=None):
+    """
+    Return the aggregate attestation
+    """
+    assert is_post_eip7549(spec)
+    attestations = list(get_valid_attestations_at_slot(
+        state, spec, slot_to_attest,
+        participation_fn=participation_fn,
+        beacon_block_root=beacon_block_root,
+    ))
+    if len(attestations) == 0:
+        return None
+    aggregate = spec.Attestation(data=attestations[0].data)
+
+    # fill in committee_bits
+    all_committee_indices = []
+    for attestation in attestations:
+        committee_indices_of_attestation = spec.get_committee_indices(attestation.committee_bits)
+        assert len(committee_indices_of_attestation) == 1
+        all_committee_indices += committee_indices_of_attestation
+
+    all_committee_indices = set(all_committee_indices)
+    for committee_index in all_committee_indices:
+        aggregate.committee_bits[committee_index] = True
+
+    # aggregate the attestation data and sigs
+    aggregate.aggregation_bits = get_empty_eip7549_aggregation_bits(
+        spec, state, aggregate.committee_bits, slot_to_attest)
+    for attestation in attestations:
+        committee_indices_of_attestation = spec.get_committee_indices(attestation.committee_bits)
+        assert len(committee_indices_of_attestation) == 1
+        committee_index = committee_indices_of_attestation[0]
+        offset = get_eip7549_aggregation_bits_offset(
+            spec, state, attestation.data.slot, aggregate.committee_bits, committee_index)
+        for i in range(len(attestation.aggregation_bits)):
+            aggregation_bits_index = offset + i
+            aggregate.aggregation_bits[aggregation_bits_index] = attestation.aggregation_bits[i]
+    aggregate.signature = bls.Aggregate([attestation.signature for attestation in attestations])
+
+    return aggregate
+
+
 def next_slots_with_attestations(spec,
                                  state,
                                  slot_count,
@@ -249,6 +291,26 @@ def next_slots_with_attestations(spec,
     return state, signed_blocks, post_state
 
 
+def _add_valid_attestations(spec, state, block, slot_to_attest, participation_fn=None):
+    if is_post_eip7549(spec):
+        attestation = get_valid_attestation_at_slot(
+            state,
+            spec,
+            slot_to_attest,
+            participation_fn=participation_fn,
+        )
+        block.body.attestations.append(attestation)
+    else:
+        attestations = get_valid_attestations_at_slot(
+            state,
+            spec,
+            slot_to_attest,
+            participation_fn=participation_fn,
+        )
+        for attestation in attestations:
+            block.body.attestations.append(attestation)
+
+
 def next_epoch_with_attestations(spec,
                                  state,
                                  fill_cur_epoch,
@@ -281,24 +343,10 @@ def state_transition_with_full_block(spec,
     if fill_cur_epoch and state.slot >= spec.MIN_ATTESTATION_INCLUSION_DELAY:
         slot_to_attest = state.slot - spec.MIN_ATTESTATION_INCLUSION_DELAY + 1
         if slot_to_attest >= spec.compute_start_slot_at_epoch(spec.get_current_epoch(state)):
-            attestations = get_valid_attestation_at_slot(
-                state,
-                spec,
-                slot_to_attest,
-                participation_fn=participation_fn
-            )
-            for attestation in attestations:
-                block.body.attestations.append(attestation)
+            _add_valid_attestations(spec, state, block, slot_to_attest, participation_fn=participation_fn)
     if fill_prev_epoch and state.slot >= spec.SLOTS_PER_EPOCH:
         slot_to_attest = state.slot - spec.SLOTS_PER_EPOCH + 1
-        attestations = get_valid_attestation_at_slot(
-            state,
-            spec,
-            slot_to_attest,
-            participation_fn=participation_fn
-        )
-        for attestation in attestations:
-            block.body.attestations.append(attestation)
+        _add_valid_attestations(spec, state, block, slot_to_attest, participation_fn=participation_fn)
     if sync_aggregate is not None:
         block.body.sync_aggregate = sync_aggregate
 
@@ -319,7 +367,7 @@ def state_transition_with_full_attestations_block(spec, state, fill_cur_epoch, f
         slots = state.slot % spec.SLOTS_PER_EPOCH
         for slot_offset in range(slots):
             target_slot = state.slot - slot_offset
-            attestations += get_valid_attestation_at_slot(
+            attestations += get_valid_attestations_at_slot(
                 state,
                 spec,
                 target_slot,
@@ -330,7 +378,7 @@ def state_transition_with_full_attestations_block(spec, state, fill_cur_epoch, f
         slots = spec.SLOTS_PER_EPOCH - state.slot % spec.SLOTS_PER_EPOCH
         for slot_offset in range(1, slots):
             target_slot = state.slot - (state.slot % spec.SLOTS_PER_EPOCH) - slot_offset
-            attestations += get_valid_attestation_at_slot(
+            attestations += get_valid_attestations_at_slot(
                 state,
                 spec,
                 target_slot,
@@ -423,6 +471,7 @@ def get_empty_eip7549_aggregation_bits(spec, state, committee_bits, slot):
 
 
 def get_eip7549_aggregation_bits_offset(spec, state, slot, committee_bits, committee_index):
+    # FIXME: it's not efficient to use it as an aggregator
     committee_indices = spec.get_committee_indices(committee_bits)
     assert committee_index in committee_indices
     offset = 0
diff --git a/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_get_proposer_head.py b/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_get_proposer_head.py
index 9419a18df..81e5b4f56 100644
--- a/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_get_proposer_head.py
+++ b/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_get_proposer_head.py
@@ -4,7 +4,7 @@ from eth2spec.test.context import (
     with_altair_and_later,
 )
 from eth2spec.test.helpers.attestations import (
-    get_valid_attestation_at_slot,
+    get_valid_attestations_at_slot,
 )
 from eth2spec.test.helpers.block import (
     build_empty_block_for_next_slot,
@@ -101,7 +101,7 @@ def test_basic_is_parent_root(spec, state):
     # Fill a slot with attestations to its parent
     block = build_empty_block_for_next_slot(spec, state)
     parent_block_slot = block.slot - 1
-    block.body.attestations = get_valid_attestation_at_slot(
+    block.body.attestations = get_valid_attestations_at_slot(
         state,
         spec,
         parent_block_slot,
@@ -128,7 +128,7 @@ def test_basic_is_parent_root(spec, state):
     slot = state.slot
 
     # Add attestations to the parent block
-    attestations = get_valid_attestation_at_slot(
+    attestations = get_valid_attestations_at_slot(
         state,
         spec,
         slot_to_attest=slot - 1,
diff --git a/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_reorg.py b/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_reorg.py
index ca9b483f8..983a8ee66 100644
--- a/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_reorg.py
+++ b/tests/core/pyspec/eth2spec/test/phase0/fork_choice/test_reorg.py
@@ -9,7 +9,7 @@ from eth2spec.test.helpers.constants import (
 from eth2spec.test.helpers.attestations import (
     state_transition_with_full_block,
     get_valid_attestation,
-    get_valid_attestation_at_slot,
+    get_valid_attestations_at_slot,
 )
 from eth2spec.test.helpers.block import (
     build_empty_block,
@@ -218,7 +218,7 @@ def _run_delayed_justification(spec, state, attemped_reorg, is_justifying_previo
     # add attestations of y
     temp_state = state.copy()
     next_slot(spec, temp_state)
-    attestations_for_y = list(get_valid_attestation_at_slot(temp_state, spec, signed_block_y.message.slot))
+    attestations_for_y = list(get_valid_attestations_at_slot(temp_state, spec, signed_block_y.message.slot))
     current_time = temp_state.slot * spec.config.SECONDS_PER_SLOT + store.genesis_time
     on_tick_and_append_step(spec, store, current_time, test_steps)
     yield from add_attestations(spec, store, attestations_for_y, test_steps)
@@ -345,10 +345,10 @@ def _run_include_votes_of_another_empty_chain(spec, state, enough_ffg, is_justif
     # create 2/3 votes for the empty chain
     attestations_for_y = []
     # target_is_current = not is_justifying_previous_epoch
-    attestations = list(get_valid_attestation_at_slot(state, spec, state_a.slot))
+    attestations = list(get_valid_attestations_at_slot(state, spec, state_a.slot))
     attestations_for_y.append(attestations)
     for state in states_of_empty_chain:
-        attestations = list(get_valid_attestation_at_slot(state, spec, state.slot))
+        attestations = list(get_valid_attestations_at_slot(state, spec, state.slot))
         attestations_for_y.append(attestations)
 
     state = state_a.copy()

From 265788be58cfbcdd7280d17eedc309eb0bef0347 Mon Sep 17 00:00:00 2001
From: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
Date: Thu, 4 Apr 2024 18:01:08 +0900
Subject: [PATCH 12/25] refactor

---
 .../eth2spec/test/helpers/attestations.py     | 75 +++++++++++++------
 1 file changed, 53 insertions(+), 22 deletions(-)

diff --git a/tests/core/pyspec/eth2spec/test/helpers/attestations.py b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
index e57eb8318..567bbd4c4 100644
--- a/tests/core/pyspec/eth2spec/test/helpers/attestations.py
+++ b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
@@ -225,6 +225,51 @@ def get_valid_attestations_at_slot(state, spec, slot_to_attest, participation_fn
         )
 
 
+def _get_aggregate_committee_indices(spec, attestations):
+    """
+    Aggregate all unique committee indices from the given attestations.
+    """
+    all_committee_indices = set()
+    for attestation in attestations:
+        committee_indices = spec.get_committee_indices(attestation.committee_bits)
+        assert len(committee_indices) == 1
+        all_committee_indices.add(committee_indices[0])
+
+    return all_committee_indices
+
+
+def _aggregate_aggregation_bits_and_signatures(spec, state, slot, aggregate, attestations):
+    """
+    Aggregate the aggregation bits and signatures from the attestations,
+    incorporating the calculation of aggregation bits offset directly.
+    """
+    # initialize aggregation bits for the aggregate attestation
+    aggregate.aggregation_bits = get_empty_eip7549_aggregation_bits(
+        spec, state, aggregate.committee_bits, slot)
+
+    signatures = []
+
+    offset = 0
+    attestations = sorted(attestations, key=lambda att: spec.get_committee_indices(att.committee_bits)[0])
+    for attestation in attestations:
+        # retrieve the single committee index for the attestation.
+        committee_index = spec.get_committee_indices(attestation.committee_bits)[0]
+
+        # update the aggregate's aggregation bits based on each attestation.
+        for i, bit in enumerate(attestation.aggregation_bits):
+            aggregate.aggregation_bits[offset + i] = bit
+
+        # collect signatures for aggregation.
+        signatures.append(attestation.signature)
+
+        # update offset
+        committee = spec.get_beacon_committee(state, slot, committee_index)
+        offset += len(committee)
+
+    # aggregate signatures from all attestations.
+    aggregate.signature = bls.Aggregate(signatures)
+
+
 def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=None, beacon_block_root=None):
     """
     Return the aggregate attestation
@@ -235,34 +280,18 @@ def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=
         participation_fn=participation_fn,
         beacon_block_root=beacon_block_root,
     ))
-    if len(attestations) == 0:
+    if not attestations:
         return None
+
+    # initialize the aggregate attestation.
     aggregate = spec.Attestation(data=attestations[0].data)
 
     # fill in committee_bits
-    all_committee_indices = []
-    for attestation in attestations:
-        committee_indices_of_attestation = spec.get_committee_indices(attestation.committee_bits)
-        assert len(committee_indices_of_attestation) == 1
-        all_committee_indices += committee_indices_of_attestation
-
-    all_committee_indices = set(all_committee_indices)
+    all_committee_indices = _get_aggregate_committee_indices(spec, attestations)
     for committee_index in all_committee_indices:
         aggregate.committee_bits[committee_index] = True
 
-    # aggregate the attestation data and sigs
-    aggregate.aggregation_bits = get_empty_eip7549_aggregation_bits(
-        spec, state, aggregate.committee_bits, slot_to_attest)
-    for attestation in attestations:
-        committee_indices_of_attestation = spec.get_committee_indices(attestation.committee_bits)
-        assert len(committee_indices_of_attestation) == 1
-        committee_index = committee_indices_of_attestation[0]
-        offset = get_eip7549_aggregation_bits_offset(
-            spec, state, attestation.data.slot, aggregate.committee_bits, committee_index)
-        for i in range(len(attestation.aggregation_bits)):
-            aggregation_bits_index = offset + i
-            aggregate.aggregation_bits[aggregation_bits_index] = attestation.aggregation_bits[i]
-    aggregate.signature = bls.Aggregate([attestation.signature for attestation in attestations])
+    _aggregate_aggregation_bits_and_signatures(spec, state, slot_to_attest, aggregate, attestations)
 
     return aggregate
 
@@ -471,7 +500,9 @@ def get_empty_eip7549_aggregation_bits(spec, state, committee_bits, slot):
 
 
 def get_eip7549_aggregation_bits_offset(spec, state, slot, committee_bits, committee_index):
-    # FIXME: it's not efficient to use it as an aggregator
+    """
+    Calculate the offset for the aggregation bits based on the committee index.
+    """
     committee_indices = spec.get_committee_indices(committee_bits)
     assert committee_index in committee_indices
     offset = 0

From 4f8fb6f7162e4559a4d051b0cf6996e125911806 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Thu, 4 Apr 2024 14:49:25 +0300
Subject: [PATCH 13/25] Update specs/_features/eip7251/beacon-chain.md

Co-authored-by: fradamt <104826920+fradamt@users.noreply.github.com>
---
 specs/_features/eip7251/beacon-chain.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 845ff1b96..662d851c4 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -909,7 +909,7 @@ def process_execution_layer_withdraw_request(
 
         return
 
-    has_sufficient_effective_balance = validator.effective_balance == MIN_ACTIVATION_BALANCE
+    has_sufficient_effective_balance = validator.effective_balance >= MIN_ACTIVATION_BALANCE
     has_excess_balance = state.balances[index] > MIN_ACTIVATION_BALANCE + pending_balance_to_withdraw
 
     # Only allow partial withdrawals with compounding withdrawal credentials

From ace9db9aa9a75ff1231a9631af598728d311763b Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Fri, 5 Apr 2024 15:35:06 +0300
Subject: [PATCH 14/25] Set FULL_EXIT_REQUEST_AMOUNT to 0

---
 specs/_features/eip7251/beacon-chain.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 662d851c4..852742a64 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -94,7 +94,7 @@ The following values are (non-configurable) constants used throughout the specif
 
 | Name | Value |
 | - | - |
-| `FULL_EXIT_REQUEST_AMOUNT` | `uint64(2**64 - 1)` |
+| `FULL_EXIT_REQUEST_AMOUNT` | `uint64(0)` |
 
 ### Withdrawal prefixes
 
@@ -1001,4 +1001,4 @@ def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVolu
     assert get_pending_balance_to_withdraw(state, voluntary_exit.validator_index) == 0  # [New in EIP7251]
     # Initiate exit
     initiate_validator_exit(state, voluntary_exit.validator_index)
-```
\ No newline at end of file
+```

From 3d3ec8fbba55c8067e8cbae1dce03777b9c0dd70 Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Fri, 5 Apr 2024 09:38:32 -0600
Subject: [PATCH 15/25] Update
 tests/core/pyspec/eth2spec/test/helpers/attestations.py

---
 tests/core/pyspec/eth2spec/test/helpers/attestations.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/core/pyspec/eth2spec/test/helpers/attestations.py b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
index 567bbd4c4..0562ec9b8 100644
--- a/tests/core/pyspec/eth2spec/test/helpers/attestations.py
+++ b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
@@ -272,7 +272,8 @@ def _aggregate_aggregation_bits_and_signatures(spec, state, slot, aggregate, att
 
 def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=None, beacon_block_root=None):
     """
-    Return the aggregate attestation
+    Return the aggregate attestation post EIP-7549. 
+    Note: this EIP supports dense packing of on-chain aggregates so we can just return a single `Attestation`.
     """
     assert is_post_eip7549(spec)
     attestations = list(get_valid_attestations_at_slot(

From a56bd85674d4c35164a4877bf7878326fef8e35f Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Fri, 5 Apr 2024 09:43:48 -0600
Subject: [PATCH 16/25] Update
 tests/core/pyspec/eth2spec/test/helpers/attestations.py

---
 tests/core/pyspec/eth2spec/test/helpers/attestations.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/core/pyspec/eth2spec/test/helpers/attestations.py b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
index 0562ec9b8..916a7ca00 100644
--- a/tests/core/pyspec/eth2spec/test/helpers/attestations.py
+++ b/tests/core/pyspec/eth2spec/test/helpers/attestations.py
@@ -272,7 +272,7 @@ def _aggregate_aggregation_bits_and_signatures(spec, state, slot, aggregate, att
 
 def get_valid_attestation_at_slot(state, spec, slot_to_attest, participation_fn=None, beacon_block_root=None):
     """
-    Return the aggregate attestation post EIP-7549. 
+    Return the aggregate attestation post EIP-7549.
     Note: this EIP supports dense packing of on-chain aggregates so we can just return a single `Attestation`.
     """
     assert is_post_eip7549(spec)

From 6ad0c07c78f5c8da0f783032c067e4e2c6d413c8 Mon Sep 17 00:00:00 2001
From: NC <adrninistrator1@protonmail.com>
Date: Sat, 6 Apr 2024 22:53:04 +0800
Subject: [PATCH 17/25] Remove extra ` queue_excess_active_balance` call

---
 specs/_features/eip7251/fork.md | 1 -
 1 file changed, 1 deletion(-)

diff --git a/specs/_features/eip7251/fork.md b/specs/_features/eip7251/fork.md
index 609b4f3f8..02d73deb1 100644
--- a/specs/_features/eip7251/fork.md
+++ b/specs/_features/eip7251/fork.md
@@ -129,7 +129,6 @@ def upgrade_to_eip7251(pre: deneb.BeaconState) -> BeaconState:
     )
 
     # Ensure early adopters of compounding credentials go through the activation churn
-    queue_excess_active_balance(post)
     for index, validator in enumerate(post.validators):
         if has_compounding_withdrawal_credential(validator):
             queue_excess_active_balance(post, index)

From 982a983072f82b64289a1dc82eced7320ed92d9f Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Sat, 6 Apr 2024 10:43:35 -0600
Subject: [PATCH 18/25] EIP-7251: format/lint fixes/docs, add validator guide

---
 specs/_features/eip7251/beacon-chain.md | 31 +++++++----
 specs/_features/eip7251/fork.md         |  3 +-
 specs/_features/eip7251/validator.md    | 73 +++++++++++++++++++++++++
 3 files changed, 93 insertions(+), 14 deletions(-)
 create mode 100644 specs/_features/eip7251/validator.md

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 9fbc587c5..5a99ad4d4 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -81,7 +81,7 @@
 
 ## Introduction
 
-See [a modest proposal](https://notes.ethereum.org/@mikeneuder/increase-maxeb), the [diff view](https://github.com/michaelneuder/consensus-specs/pull/3/files) and 
+See [a modest proposal](https://notes.ethereum.org/@mikeneuder/increase-maxeb), the [diff view](https://github.com/michaelneuder/consensus-specs/pull/3/files) and
 [security considerations](https://notes.ethereum.org/@fradamt/meb-increase-security).
 
 *Note:* This specification is built upon [Deneb](../../deneb/beacon-chain.md).
@@ -282,7 +282,7 @@ class BeaconBlockBody(Container):
     voluntary_exits: List[SignedVoluntaryExit, MAX_VOLUNTARY_EXITS]
     sync_aggregate: SyncAggregate
     # Execution
-    execution_payload: ExecutionPayload 
+    execution_payload: ExecutionPayload
     bls_to_execution_changes: List[SignedBLSToExecutionChange, MAX_BLS_TO_EXECUTION_CHANGES]
     blob_kzg_commitments: List[KZGCommitment, MAX_BLOB_COMMITMENTS_PER_BLOCK]
     consolidations: List[SignedConsolidation, MAX_CONSOLIDATIONS]  # [New in EIP-7251]
@@ -386,7 +386,7 @@ def get_churn_limit(state: BeaconState) -> Gwei:
     Return the churn limit for the current epoch.
     """
     churn = max(
-        MIN_PER_EPOCH_CHURN_LIMIT_EIP7251, 
+        MIN_PER_EPOCH_CHURN_LIMIT_EIP7251,
         get_total_active_balance(state) // CHURN_LIMIT_QUOTIENT
     )
     return churn - churn % EFFECTIVE_BALANCE_INCREMENT
@@ -472,7 +472,6 @@ def queue_excess_active_balance(state: BeaconState, index: ValidatorIndex) -> No
 
 #### New `compute_exit_epoch_and_update_churn`
 
-
 ```python
 def compute_exit_epoch_and_update_churn(state: BeaconState, exit_balance: Gwei) -> Epoch:
     earliest_exit_epoch = compute_activation_exit_epoch(get_current_epoch(state))
@@ -570,12 +569,16 @@ def process_epoch(state: BeaconState) -> None:
 
 #### Updated  `process_registry_updates`
 
+`process_registry_updates` uses the updated definition of `initiate_validator_exit`
+and changes how the activation epochs are computed for eligible validators.
+
 ```python
 def process_registry_updates(state: BeaconState) -> None:
     # Process activation eligibility and ejections
     for index, validator in enumerate(state.validators):
         if is_eligible_for_activation_queue(validator):
             validator.activation_eligibility_epoch = get_current_epoch(state) + 1
+
         if (
             is_active_validator(validator, get_current_epoch(state))
             and validator.effective_balance <= EJECTION_BALANCE
@@ -607,7 +610,7 @@ def process_pending_balance_deposits(state: BeaconState) -> None:
     state.pending_balance_deposits = state.pending_balance_deposits[next_deposit_index:]
 
     if len(state.pending_balance_deposits) == 0:
-        state.deposit_balance_to_consume = 0
+        state.deposit_balance_to_consume = Gwei(0)
     else:
         state.deposit_balance_to_consume = available_for_processing - processed_amount
 ```
@@ -638,6 +641,8 @@ def process_pending_consolidations(state: BeaconState) -> None:
 
 #### Updated `process_effective_balance_updates`
 
+`process_effective_balance_updates` is updated with a new limit for the maximum effective balance.
+
 ```python
 def process_effective_balance_updates(state: BeaconState) -> None:
     # Update effective balances with hysteresis
@@ -760,7 +765,7 @@ def process_withdrawals(state: BeaconState, payload: ExecutionPayload) -> None:
         state.next_withdrawal_validator_index = next_validator_index
 ```
 
-#### Operations 
+#### Operations
 
 ##### Updated `process_operations`
 
@@ -779,14 +784,16 @@ def process_operations(state: BeaconState, body: BeaconBlockBody) -> None:
     for_ops(body.deposits, process_deposit)  # [Modified in EIP7251]
     for_ops(body.voluntary_exits, process_voluntary_exit)  # [Modified in EIP7251]
     for_ops(body.bls_to_execution_changes, process_bls_to_execution_change)
-    for_ops(body.execution_payload.withdraw_requests, process_execution_layer_withdraw_request)  # New in EIP7251
-    for_ops(body.consolidations, process_consolidation)  # New in EIP7251
+    for_ops(body.execution_payload.withdraw_requests, process_execution_layer_withdraw_request)  # [New in EIP7251]
+    for_ops(body.consolidations, process_consolidation)  # [New in EIP7251]
 ```
 
 ##### Deposits
 
 ###### Updated  `apply_deposit`
 
+*NOTE*: `process_deposit` is updated with a new definition of `apply_deposit`.
+
 ```python
 def apply_deposit(state: BeaconState,
                   pubkey: BLSPubkey,
@@ -819,7 +826,7 @@ def apply_deposit(state: BeaconState,
 def is_valid_deposit_signature(pubkey: BLSPubkey,
                                withdrawal_credentials: Bytes32,
                                amount: uint64,
-                               signature: BLSSignature) -> None:
+                               signature: BLSSignature) -> bool:
     deposit_message = DepositMessage(
         pubkey=pubkey,
         withdrawal_credentials=withdrawal_credentials,
@@ -862,7 +869,7 @@ def get_validator_from_deposit(pubkey: BLSPubkey, withdrawal_credentials: Bytes3
     )
 ```
 
-##### Withdrawals 
+##### Withdrawals
 
 ###### New `process_execution_layer_withdraw_request`
 
@@ -874,7 +881,7 @@ def process_execution_layer_withdraw_request(
     amount = execution_layer_withdraw_request.amount
     is_full_exit_request = amount == FULL_EXIT_REQUEST_AMOUNT
 
-    # If partial withdrawal queue is full, only full exits are processed 
+    # If partial withdrawal queue is full, only full exits are processed
     if len(state.pending_partial_withdrawals) >= PENDING_PARTIAL_WITHDRAWALS_LIMIT and not is_full_exit_request:
         return
 
@@ -947,7 +954,7 @@ def process_consolidation(state: BeaconState, signed_consolidation: SignedConsol
     assert source_validator.exit_epoch == FAR_FUTURE_EPOCH
     assert target_validator.exit_epoch == FAR_FUTURE_EPOCH
     # Consolidations must specify an epoch when they become valid; they are not valid before then
-    assert current_epoch >= consolidation.epoch 
+    assert current_epoch >= consolidation.epoch
 
     # Verify the source and the target have Execution layer withdrawal credentials
     assert has_execution_withdrawal_credential(source_validator)
diff --git a/specs/_features/eip7251/fork.md b/specs/_features/eip7251/fork.md
index 02d73deb1..49e01ea7e 100644
--- a/specs/_features/eip7251/fork.md
+++ b/specs/_features/eip7251/fork.md
@@ -131,8 +131,7 @@ def upgrade_to_eip7251(pre: deneb.BeaconState) -> BeaconState:
     # Ensure early adopters of compounding credentials go through the activation churn
     for index, validator in enumerate(post.validators):
         if has_compounding_withdrawal_credential(validator):
-            queue_excess_active_balance(post, index)
+            queue_excess_active_balance(post, ValidatorIndex(index))
 
     return post
 ```
-
diff --git a/specs/_features/eip7251/validator.md b/specs/_features/eip7251/validator.md
new file mode 100644
index 000000000..455699383
--- /dev/null
+++ b/specs/_features/eip7251/validator.md
@@ -0,0 +1,73 @@
+# EIP-7251 -- Honest Validator
+
+## Table of contents
+
+<!-- TOC -->
+<!-- START doctoc generated TOC please keep comment here to allow auto update -->
+<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
+
+- [Introduction](#introduction)
+- [Prerequisites](#prerequisites)
+- [Beacon chain responsibilities](#beacon-chain-responsibilities)
+  - [Block and sidecar proposal](#block-and-sidecar-proposal)
+    - [Constructing the `BeaconBlockBody`](#constructing-the-beaconblockbody)
+      - [ExecutionPayload](#executionpayload)
+
+<!-- END doctoc generated TOC please keep comment here to allow auto update -->
+<!-- /TOC -->
+
+## Introduction
+
+This document represents the changes to be made in the code of an "honest validator".
+
+## Prerequisites
+
+This document is an extension of the [Deneb -- Honest Validator](../deneb/validator.md) guide.
+All behaviors and definitions defined in this document, and documents it extends, carry over unless explicitly noted or overridden.
+
+All terminology, constants, functions, and protocol mechanics defined in the updated [Beacon Chain doc of EIP-7251](./beacon-chain.md) are requisite for this document and used throughout.
+Please see related Beacon Chain doc before continuing and use them as a reference throughout.
+
+## Beacon chain responsibilities
+
+All validator responsibilities remain unchanged other than those noted below.
+
+### Block and sidecar proposal
+
+#### Constructing the `BeaconBlockBody`
+
+##### ExecutionPayload
+
+`prepare_execution_payload` is updated from the Deneb specs.
+
+*Note*: In this section, `state` is the state of the slot for the block proposal _without_ the block yet applied.
+That is, `state` is the `previous_state` processed through any empty slots up to the assigned slot using `process_slots(previous_state, slot)`.
+
+*Note*: The only change to `prepare_execution_payload` is the new definition of `get_expected_withdrawals`.
+
+```python
+def prepare_execution_payload(state: BeaconState,
+                              safe_block_hash: Hash32,
+                              finalized_block_hash: Hash32,
+                              suggested_fee_recipient: ExecutionAddress,
+                              execution_engine: ExecutionEngine) -> Optional[PayloadId]:
+    # Verify consistency of the parent hash with respect to the previous execution payload header
+    parent_hash = state.latest_execution_payload_header.block_hash
+
+    # Set the forkchoice head and initiate the payload build process
+    withdrawals, _ = get_expected_withdrawals(state)  # [Modified in EIP-7251]
+
+    payload_attributes = PayloadAttributes(
+        timestamp=compute_timestamp_at_slot(state, state.slot),
+        prev_randao=get_randao_mix(state, get_current_epoch(state)),
+        suggested_fee_recipient=suggested_fee_recipient,
+        withdrawals=withdrawals,
+        parent_beacon_block_root=hash_tree_root(state.latest_block_header),
+    )
+    return execution_engine.notify_forkchoice_updated(
+        head_block_hash=parent_hash,
+        safe_block_hash=safe_block_hash,
+        finalized_block_hash=finalized_block_hash,
+        payload_attributes=payload_attributes,
+    )
+```

From a80a7775896c7cd8d9ae077be383ac23c3e68a4b Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Sat, 6 Apr 2024 11:15:03 -0600
Subject: [PATCH 19/25] add missing extended types for EIP-7251

---
 specs/_features/eip7251/beacon-chain.md | 55 +++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 5a99ad4d4..8434e8378 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -30,6 +30,8 @@
   - [Extended Containers](#extended-containers)
     - [`BeaconState`](#beaconstate)
     - [`BeaconBlockBody`](#beaconblockbody)
+    - [`ExecutionPayload`](#executionpayload)
+    - [`ExecutionPayloadHeader`](#executionpayloadheader)
 - [Helpers](#helpers)
   - [Predicates](#predicates)
     - [Updated `is_eligible_for_activation_queue`](#updated-is_eligible_for_activation_queue)
@@ -136,6 +138,7 @@ The following values are (non-configurable) constants used throughout the specif
 
 | Name | Value | Description |
 | - | - | - |
+| `MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD` | `uint64(16)` |
 | `MAX_PARTIAL_WITHDRAWALS_PER_PAYLOAD` | `uint64(2**3)` (= 8) | Maximum amount of partial withdrawals allowed in each payload |
 
 ### State list lengths
@@ -288,6 +291,58 @@ class BeaconBlockBody(Container):
     consolidations: List[SignedConsolidation, MAX_CONSOLIDATIONS]  # [New in EIP-7251]
 ```
 
+#### `ExecutionPayload`
+
+```python
+class ExecutionPayload(Container):
+    # Execution block header fields
+    parent_hash: Hash32
+    fee_recipient: ExecutionAddress  # 'beneficiary' in the yellow paper
+    state_root: Bytes32
+    receipts_root: Bytes32
+    logs_bloom: ByteVector[BYTES_PER_LOGS_BLOOM]
+    prev_randao: Bytes32  # 'difficulty' in the yellow paper
+    block_number: uint64  # 'number' in the yellow paper
+    gas_limit: uint64
+    gas_used: uint64
+    timestamp: uint64
+    extra_data: ByteList[MAX_EXTRA_DATA_BYTES]
+    base_fee_per_gas: uint256
+    # Extra payload fields
+    block_hash: Hash32  # Hash of execution block
+    transactions: List[Transaction, MAX_TRANSACTIONS_PER_PAYLOAD]
+    withdrawals: List[Withdrawal, MAX_WITHDRAWALS_PER_PAYLOAD]
+    blob_gas_used: uint64
+    excess_blob_gas: uint64
+    withdraw_requests: List[ExecutionLayerWithdrawRequest, MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD]  # [New in EIP-7251]
+```
+
+#### `ExecutionPayloadHeader`
+
+```python
+class ExecutionPayloadHeader(Container):
+    # Execution block header fields
+    parent_hash: Hash32
+    fee_recipient: ExecutionAddress
+    state_root: Bytes32
+    receipts_root: Bytes32
+    logs_bloom: ByteVector[BYTES_PER_LOGS_BLOOM]
+    prev_randao: Bytes32
+    block_number: uint64
+    gas_limit: uint64
+    gas_used: uint64
+    timestamp: uint64
+    extra_data: ByteList[MAX_EXTRA_DATA_BYTES]
+    base_fee_per_gas: uint256
+    # Extra payload fields
+    block_hash: Hash32  # Hash of execution block
+    transactions_root: Root
+    withdrawals_root: Root
+    blob_gas_used: uint64
+    excess_blob_gas: uint64
+    withdraw_requests_root: Root  # [New in EIP-7251]
+```
+
 ## Helpers
 
 ### Predicates

From b5d7bd0a8afb7bb34ad5de297aceef99e8823edf Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Sat, 6 Apr 2024 11:38:33 -0600
Subject: [PATCH 20/25] bugfix: voluntary exit processing in EIP-7251

---
 specs/_features/eip7251/beacon-chain.md | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 8434e8378..75eae939d 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -1051,12 +1051,12 @@ def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVolu
     assert get_current_epoch(state) >= voluntary_exit.epoch
     # Verify the validator has been active long enough
     assert get_current_epoch(state) >= validator.activation_epoch + SHARD_COMMITTEE_PERIOD
-    # Verify signature
-    domain = get_domain(state, DOMAIN_VOLUNTARY_EXIT, voluntary_exit.epoch)
-    signing_root = compute_signing_root(voluntary_exit, domain)
-    assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
     # Only exit validator if it has no pending withdrawals in the queue
     assert get_pending_balance_to_withdraw(state, voluntary_exit.validator_index) == 0  # [New in EIP7251]
+    # Verify signature
+    domain = compute_domain(DOMAIN_VOLUNTARY_EXIT, CAPELLA_FORK_VERSION, state.genesis_validators_root)
+    signing_root = compute_signing_root(voluntary_exit, domain)
+    assert bls.Verify(validator.pubkey, signing_root, signed_voluntary_exit.signature)
     # Initiate exit
     initiate_validator_exit(state, voluntary_exit.validator_index)
 ```

From 61168e6124e1b5c7359ff131ca779e4c1768b68a Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Sat, 6 Apr 2024 13:30:12 -0600
Subject: [PATCH 21/25] spec bugfix: incorrect `process_epoch` definition

---
 specs/_features/eip7251/beacon-chain.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 75eae939d..c40b0faa1 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -620,6 +620,9 @@ def process_epoch(state: BeaconState) -> None:
     process_effective_balance_updates(state)  # [Modified in EIP7251]
     process_slashings_reset(state)
     process_randao_mixes_reset(state)
+    process_historical_summaries_update(state)
+    process_participation_flag_updates(state)
+    process_sync_committee_updates(state)
 ```
 
 #### Updated  `process_registry_updates`

From 8cf2fd50f601008f79be79d925f7621262dbd887 Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Sat, 6 Apr 2024 14:21:36 -0600
Subject: [PATCH 22/25] add EIP-7251 `initialize_beacon_state_from_eth1`
 function

---
 specs/_features/eip7251/beacon-chain.md | 59 +++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index c40b0faa1..ab627c90a 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -77,6 +77,7 @@
         - [New `process_consolidation`](#new-process_consolidation)
       - [Voluntary exits](#voluntary-exits)
         - [Updated `process_voluntary_exit`](#updated-process_voluntary_exit)
+- [Testing](#testing)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 <!-- /TOC -->
@@ -1063,3 +1064,61 @@ def process_voluntary_exit(state: BeaconState, signed_voluntary_exit: SignedVolu
     # Initiate exit
     initiate_validator_exit(state, voluntary_exit.validator_index)
 ```
+
+## Testing
+
+*Note*: The function `initialize_beacon_state_from_eth1` is modified for pure EIP-7251 testing only.
+
+```python
+def initialize_beacon_state_from_eth1(eth1_block_hash: Hash32,
+                                      eth1_timestamp: uint64,
+                                      deposits: Sequence[Deposit],
+                                      execution_payload_header: ExecutionPayloadHeader=ExecutionPayloadHeader()
+                                      ) -> BeaconState:
+    fork = Fork(
+        previous_version=EIP7251_FORK_VERSION,  # [Modified in EIP-7251] for testing only
+        current_version=EIP7251_FORK_VERSION,  # [Modified in EIP-7251]
+        epoch=GENESIS_EPOCH,
+    )
+    state = BeaconState(
+        genesis_time=eth1_timestamp + GENESIS_DELAY,
+        fork=fork,
+        eth1_data=Eth1Data(block_hash=eth1_block_hash, deposit_count=uint64(len(deposits))),
+        latest_block_header=BeaconBlockHeader(body_root=hash_tree_root(BeaconBlockBody())),
+        randao_mixes=[eth1_block_hash] * EPOCHS_PER_HISTORICAL_VECTOR,  # Seed RANDAO with Eth1 entropy
+    )
+
+    # Process deposits
+    leaves = list(map(lambda deposit: deposit.data, deposits))
+    for index, deposit in enumerate(deposits):
+        deposit_data_list = List[DepositData, 2**DEPOSIT_CONTRACT_TREE_DEPTH](*leaves[:index + 1])
+        state.eth1_data.deposit_root = hash_tree_root(deposit_data_list)
+        process_deposit(state, deposit)
+
+    # Process deposit balance updates
+    for deposit in state.pending_balance_deposits:
+        increase_balance(state, deposit.index, deposit.amount)
+    state.pending_balance_deposits = []
+
+    # Process activations
+    for index, validator in enumerate(state.validators):
+        balance = state.balances[index]
+        validator.effective_balance = min(balance - balance % EFFECTIVE_BALANCE_INCREMENT, MAX_EFFECTIVE_BALANCE)
+        if validator.effective_balance == MAX_EFFECTIVE_BALANCE:
+            validator.activation_eligibility_epoch = GENESIS_EPOCH
+            validator.activation_epoch = GENESIS_EPOCH
+
+    # Set genesis validators root for domain separation and chain versioning
+    state.genesis_validators_root = hash_tree_root(state.validators)
+
+    # Fill in sync committees
+    # Note: A duplicate committee is assigned for the current and next committee at genesis
+    state.current_sync_committee = get_next_sync_committee(state)
+    state.next_sync_committee = get_next_sync_committee(state)
+
+    # Initialize the execution payload header
+    # If empty, will initialize a chain that has not yet gone through the Merge transition
+    state.latest_execution_payload_header = execution_payload_header
+
+    return state
+```

From 64da0da132f6a677b60b68a27e66aa16ed04a526 Mon Sep 17 00:00:00 2001
From: Mikhail Kalinin <noblesse.knight@gmail.com>
Date: Sun, 7 Apr 2024 18:15:01 +0600
Subject: [PATCH 23/25] Fix has_sufficient_effective_balance computation

---
 specs/_features/eip7251/beacon-chain.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/specs/_features/eip7251/beacon-chain.md b/specs/_features/eip7251/beacon-chain.md
index 9fbc587c5..7d7e78d4a 100644
--- a/specs/_features/eip7251/beacon-chain.md
+++ b/specs/_features/eip7251/beacon-chain.md
@@ -686,7 +686,7 @@ def get_expected_withdrawals(state: BeaconState) -> Tuple[Sequence[Withdrawal],
             break
 
         validator = state.validators[withdrawal.index]
-        has_sufficient_effective_balance = validator.effective_balance == MIN_ACTIVATION_BALANCE
+        has_sufficient_effective_balance = validator.effective_balance >= MIN_ACTIVATION_BALANCE
         has_excess_balance = state.balances[withdrawal.index] > MIN_ACTIVATION_BALANCE
         if validator.exit_epoch == FAR_FUTURE_EPOCH and has_sufficient_effective_balance and has_excess_balance:
             withdrawable_balance = min(state.balances[withdrawal.index] - MIN_ACTIVATION_BALANCE, withdrawal.amount)

From 3cf3e21504a661b8af9ab744f83ffac8b2fd4ec4 Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Mon, 8 Apr 2024 16:28:17 -0600
Subject: [PATCH 24/25] Update beacon-chain.md

---
 specs/_features/eip7002/beacon-chain.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/specs/_features/eip7002/beacon-chain.md b/specs/_features/eip7002/beacon-chain.md
index 39b03e878..58af0d540 100644
--- a/specs/_features/eip7002/beacon-chain.md
+++ b/specs/_features/eip7002/beacon-chain.md
@@ -222,7 +222,10 @@ def process_operations(state: BeaconState, body: BeaconBlockBody) -> None:
 ```python
 def process_execution_layer_exit(state: BeaconState, execution_layer_exit: ExecutionLayerExit) -> None:
     validator_pubkeys = [v.pubkey for v in state.validators]
-    validator_index = ValidatorIndex(validator_pubkeys.index(execution_layer_exit.validator_pubkey))
+    pubkey_to_exit = execution_layer_exit.validator_pubkey
+    if pubkey_to_exit not in validator_pubkeys:
+        return
+    validator_index = ValidatorIndex(validator_pubkeys.index(pubkey_to_exit))
     validator = state.validators[validator_index]
 
     # Verify withdrawal credentials

From 1db1c5432365cd3b480b535d960b3c1c973c970f Mon Sep 17 00:00:00 2001
From: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
Date: Tue, 9 Apr 2024 10:33:48 +0800
Subject: [PATCH 25/25] add comment

---
 specs/_features/eip7002/beacon-chain.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/specs/_features/eip7002/beacon-chain.md b/specs/_features/eip7002/beacon-chain.md
index 58af0d540..712111920 100644
--- a/specs/_features/eip7002/beacon-chain.md
+++ b/specs/_features/eip7002/beacon-chain.md
@@ -222,6 +222,7 @@ def process_operations(state: BeaconState, body: BeaconBlockBody) -> None:
 ```python
 def process_execution_layer_exit(state: BeaconState, execution_layer_exit: ExecutionLayerExit) -> None:
     validator_pubkeys = [v.pubkey for v in state.validators]
+    # Verify pubkey exists
     pubkey_to_exit = execution_layer_exit.validator_pubkey
     if pubkey_to_exit not in validator_pubkeys:
         return