Mining Integration

The reference node includes mining coordination functionality as part of the Bitcoin protocol. The system provides block template generation, mining coordination, and optional Stratum V2 protocol support.

Block Template Generation

Block templates are built from blvm-consensus helpers (e.g. template construction) aligned with Orange Paper Section 12.4, with tests and spec-lock proofs on the relevant consensus paths.

Algorithm Overview

  1. Get Chain State: Retrieve current chain tip, height, and difficulty
  2. Get Mempool Transactions: Fetch transactions from mempool
  3. Get UTXO Set: Load UTXO set for fee calculation
  4. Select Transactions: Choose transactions based on fee priority
  5. Create Coinbase: Generate coinbase transaction with subsidy + fees
  6. Calculate Merkle Root: Compute merkle root from transaction list
  7. Build Template: Construct block header with all components

Code: mining.rs

Transaction Selection

Transactions are selected using a fee-based priority algorithm:

  1. Prioritize by Fee Rate: Transactions sorted by fee rate (satoshis per byte)
  2. Size Limits: Respect maximum block size (1MB) and weight (4M weight units)
  3. Minimum Fee: Filter transactions below minimum fee rate (1 sat/vB default)
  4. UTXO Validation: Verify all transaction inputs exist in UTXO set

Code: miner.rs

Fee Calculation

Transaction fees are calculated using the UTXO set:

#![allow(unused)]
fn main() {
fee = sum(input_values) - sum(output_values)
fee_rate = fee / transaction_size
}

The coinbase transaction includes:

  • Block Subsidy: Calculated based on halving schedule
  • Transaction Fees: Sum of all fees from selected transactions

Code: miner.rs

Block Template Structure

#![allow(unused)]
fn main() {
pub struct Block {
    header: BlockHeader {
        version: 1,
        prev_block_hash: [u8; 32],
        merkle_root: [u8; 32],
        timestamp: u32,
        bits: u32,
        nonce: 0,  // To be filled by miner
    },
    transactions: Vec<Transaction>,  // Coinbase first
}
}

Code: miner.rs

Mining Process

Template Generation

The getblocktemplate RPC method generates a block template:

  1. Uses create_block_template (or equivalent) from blvm-consensus, covered by tests and upstream verification policy
  2. Converts to JSON-RPC format (BIP 22/23)
  3. Returns template ready for mining

Code: mining.rs

Proof of Work

Mining involves finding a nonce that satisfies the difficulty target:

  1. Nonce Search: Iterate through nonce values (0 to 2^32-1)
  2. Hash Calculation: Compute SHA256(SHA256(block_header))
  3. Target Check: Verify hash < difficulty target
  4. Success: Return mined block with valid nonce

Code: miner.rs

Block Submission

Mined blocks are submitted via submitblock RPC method:

  1. Validation: Block validated against consensus rules
  2. Connection: Block connected to chain
  3. Confirmation: Block added to blockchain

Code: mining.rs

Mining Coordinator

The MiningCoordinator manages mining operations:

  • Template Generation: Creates block templates from mempool
  • Mining Loop: Continuously generates and mines blocks
  • Stratum V2: Pool/miner TCP and protocol server live in the blvm-stratum-v2 module; the node exposes P2P demux and NodeAPI hooks
  • Merge Mining: Available via optional blvm-merge-mining module (paid plugin)

Code: miner.rs

Stratum V2 Support

Optional Stratum V2 protocol support provides:

  • Binary Protocol: 50-66% bandwidth savings vs Stratum V1
  • Encrypted Communication: TLS/QUIC encryption
  • Multiplexed Channels: QUIC stream multiplexing
  • Merge Mining: Simultaneous mining of multiple chains

Code: blvm-stratum-v2 (module — dedicated miner TCP); node: P2P demux in network_manager.rs, NodeAPI::send_peer_transport_payload

Configuration

There is no [mining] table on NodeConfig. Mining uses RPC (getblocktemplate, submitblock), optional blvm-stratum-v2 for Stratum traffic, and optional blvm-merge-mining.

ckpool solo (Bitaxe / Stratum V1)

Stack: synced blvm node → ckpool (-B solo) → miners on :3333.

[rpc_auth]
required = true
username = "ckpool"
password = "change-me-to-a-strong-secret"

blvm --network mainnet --rpc-addr 127.0.0.1:8332

HTTP Basic password is auto-granted admin (required for getblocktemplate / submitblock). Point ckpool btcd.url at the RPC port with matching auth / pass. Regtest lab: seed with generatetoaddress before GBT. Smoke test: blvm-node/examples/ckpool-solo/smoke-rpc.sh. See the blvm-node Integration Guide — ckpool.

Stratum V2 (node + module)

See Stratum V2 + Merge Mining for split node vs module config.toml examples and p2p_stratum_demux.

Code: config/mod.rs, StratumV2Config

See Also