babylon btc

The x/babylon module integrates QoreChain with the Babylon Protocol to inherit Bitcoin's proof-of-work finality guarantees. Through BTC restaking, QoreChain gains a secondary finality layer backed by Bitcoin's hashrate -- without requiring any changes to the Bitcoin protocol itself.

Overview

Babylon Protocol enables proof-of-stake chains to leverage Bitcoin's security through a timestamping and checkpointing mechanism. QoreChain's integration works as follows:

1. BTC stakers lock Bitcoin in Babylon staking transactions and register their positions on QoreChain.

2. Epoch checkpoints from QoreChain are periodically relayed to Babylon, which timestamps them on Bitcoin.

3. Finality inheritance: Once a QoreChain epoch is checkpointed on Bitcoin, the state covered by that epoch inherits Bitcoin's proof-of-work finality guarantees.

This provides a defense against long-range attacks and equivocation that is anchored to Bitcoin's accumulated hashrate rather than relying solely on QoreChain's own validator set.

BTC Staking Positions

Users can register BTC staking positions on QoreChain by submitting a MsgBTCRestake transaction that references a Bitcoin staking transaction.

Registration Requirements

Parameter	Value	Description
Minimum stake	100,000 satoshis (0.001 BTC)	Minimum BTC required per staking position
Unbonding period	144 BTC blocks (~1 day)	Waiting period before staked BTC can be withdrawn
Checkpoint interval	Every 10 QoreChain epochs	How often state is checkpointed to Babylon

Staking Position Structure

Each BTC staking position tracks the following on-chain state:

Field	Description
staker_address	QoreChain address of the staker (qor1...)
btc_tx_hash	Bitcoin transaction hash of the staking transaction
amount_satoshis	Amount of BTC staked in satoshis
status	Position lifecycle state: active, unbonding, or withdrawn
staked_at	Timestamp of position registration
unbonding_height	Block height at which unbonding was initiated (if applicable)
validator_addr	QoreChain validator address this stake is delegated to

Registration Flow

1

Create BTC staking transaction

On the Bitcoin Network: create the BTC staking transaction.

2

Submit MsgBTCRestake on QoreChain

On QoreChain: submit MsgBTCRestake with btc_tx_hash, amount, and validator.

3

Position recorded

Position is recorded on-chain as "active".

Epoch Checkpoints

QoreChain's epoch state roots are periodically checkpointed to Bitcoin through the Babylon relay chain.

Checkpoint Flow

1

Submit checkpoint

A QoreChain validator submits MsgSubmitBTCCheckpoint containing:

• epoch number

• BTC block hash

• BTC block height

• QoreChain state root

2

IBC relay

The checkpoint data is relayed to the Babylon chain via IBC.

3

Timestamping on Bitcoin

Babylon includes the checkpoint in a Bitcoin transaction, anchoring QoreChain's state to Bitcoin's blockchain.

4

Confirmation

Once the Bitcoin transaction is confirmed, finality flows back through Babylon to QoreChain.

5

Finalization

The checkpoint status transitions from pending to confirmed to finalized.

Checkpoint Structure

Field	Description
epoch_num	QoreChain epoch number being checkpointed
btc_block_hash	Bitcoin block hash containing the checkpoint
btc_block_height	Bitcoin block height
state_root	QoreChain state root at the epoch boundary
submitted_at	Timestamp of checkpoint submission
status	Checkpoint state: pending, confirmed, or finalized

Epoch Snapshots

At each checkpoint boundary, an epoch snapshot captures aggregate network state:

Field	Description
total_staked	Total BTC staked across all positions (satoshis)
active_positions	Number of active staking positions
validator_count	Number of validators with BTC-backed delegations
block_height	QoreChain block height at snapshot

Secondary Finality Layer

The Babylon integration provides a secondary finality guarantee that complements QoreChain's native consensus finality:

Finality Layer	Source	Speed	Security
Primary	QoreChain Consensus Engine	~5 seconds	Backed by QOR stake + PQC signatures
Secondary	Babylon + Bitcoin	~60 minutes	Backed by Bitcoin's cumulative hashrate

The secondary layer is particularly valuable for:

• Long-range attack prevention: Even if an attacker accumulates significant QOR stake, they cannot rewrite history that has been checkpointed on Bitcoin.

• Cross-chain bridge security: Bridge operations involving large values can wait for Bitcoin-level finality before releasing funds.

• Institutional confidence: The Bitcoin timestamp provides an independently verifiable proof of QoreChain's state history.

Configuration

Parameter	Default	Description
enabled	false	Master switch for BTC restaking features
min_stake_amount	100,000 satoshis	Minimum BTC per staking position
unbonding_period	144 BTC blocks	BTC-denominated unbonding duration
checkpoint_interval	10 epochs	Epochs between Babylon checkpoints
babylon_chain_id	bbn-1	Chain ID of the connected Babylon network

Events

The module emits the following on-chain events:

Event Type	Attributes	Description
btc_restake	staker, btc_tx_hash, amount, validator	New BTC staking position registered
btc_unbond	staker, amount	BTC staking position entered unbonding
btc_checkpoint	epoch, checkpoint_id	Epoch checkpoint submitted to Babylon
babylon_epoch_complete	epoch	Babylon epoch finalized with Bitcoin timestamp

API Endpoints

REST

Method	Endpoint	Description
GET	/babylon/v1/staking/{address}	Get BTC staking positions for an address
GET	/babylon/v1/checkpoint/{epoch}	Get checkpoint data for a specific epoch
GET	/babylon/v1/params	Get module configuration parameters

JSON-RPC

Method	Parameters	Description
qor_getBTCStakingPosition	address (string)	Returns the BTC staking position for the given QoreChain address

CLI Commands

Query Commands

Query BTC restaking configuration

# Query BTC restaking configuration
qorechaind query babylon config

# Query a staking position by address
qorechaind query babylon position <staker-address>

Transaction Commands

Register and submit checkpoints

# Register a BTC restaking position
qorechaind tx babylon restake \
  --btc-tx-hash <hash> \
  --amount-satoshis <amount> \
  --validator <qorvaloper1...> \
  --from <key-name>

# Submit a BTC checkpoint
qorechaind tx babylon submit-checkpoint \
  --epoch <epoch-number> \
  --btc-block-hash <hash> \
  --btc-block-height <height> \
  --state-root <root> \
  --from <key-name>