Blocks and consensus¶

Block structure¶

Every block in WaveLedger has the following fields:

Genesis is the only block with difficulty = 0 and no PoW.

Consensus rules¶

A block is valid iff:

1. previous_hash matches the tip's hash.
2. merkle_root matches a recomputed Merkle root of transactions.
3. hash matches a recomputed SHA3-512 of the header.
4. hash has at least difficulty leading hex zeros.
5. difficulty matches what the chain expects at this height.
6. quantum_signature is present and verifies against the block's quantum_seed (see Entropy).
7. The coinbase tx (transactions[0]) has sender = "mining_reward", recipient = block.miner, and amount == subsidy + collected_fees where subsidy is the schedule-derived block reward at this height.
8. Every non-coinbase tx passes the standard tx validation rules (see Transaction format).
9. Adding the coinbase would not push total_supply above MAX_SUPPLY.

Fork resolution¶

The canonical chain is the one with highest cumulative work, defined as $\sum 2^{\text{difficulty}_i}$ summed over every block.

If two blocks arrive at the same height with the same parent, the node keeps both until one chain extends. The longer-work chain wins; the other branch is reorged out and its non-coinbase txs are put back into the mempool.

Reorgs deeper than MAX_REORG_DEPTH (100 blocks) are rejected — a node that has been offline long enough to see a 100-block reorg must re-sync from peers, not from disk.

Difficulty adjustment¶

Difficulty is recalculated every DIFFICULTY_ADJUSTMENT_INTERVAL (10) blocks, at block boundaries only (not on every block). At each boundary:

• If the last interval took less than half the expected time → +1
• If the last interval took more than 2× the expected time → -1
• Otherwise hold

Mainnet bounds: [MIN_DIFFICULTY, MAX_DIFFICULTY] = [2, 8]. Testnet bounds: [2, 4] — performance-1x Fly VMs cap out at difficulty 4.

Expected time = BLOCK_TIME_TARGET * (DIFFICULTY_ADJUSTMENT_INTERVAL - 1) = 60s × 9 = 540s mainnet, 45s testnet.

Coinbase¶

The first transaction in every block is a "coinbase" — synthetic, no signature, sender = "mining_reward". Its amount is the schedule subsidy plus the sum of fees from all other txs in the block.

The subsidy is: $$ \text{subsidy}(h) = \frac{\text{INITIAL_BLOCK_REWARD}}{2^{\lfloor h / \text{HALVING_INTERVAL} \rfloor}} $$

with current values INITIAL_BLOCK_REWARD = 5 WAVE, HALVING_INTERVAL = 2,100,000 blocks. See Tokenomics for the full curve.

Mempool eligibility¶

To enter the mempool a tx must:

• Have a valid ML-DSA-87 signature
• Have fee ≥ MEMPOOL_MIN_FEE (0.0001 WAVE)
• Have amount ≥ MIN_TRANSACTION_AMOUNT (0.01 WAVE), unless it is a contract deploy/call (recipient == "contract" or data.type in ("deploy", "call")), which are exempt from the dust limit
• Pass the balance check: sender_balance - sum(pending_outflows) ≥ amount + fee
• Not be a duplicate of a tx already pending
• Not exceed MEMPOOL_MAX_PER_ADDRESS pending entries (50) from one sender

Mempool capacity is MEMPOOL_MAX_SIZE (5,000) with fee-priority eviction. Replace-by-fee is supported with a 10% minimum bump on the same (sender, nonce) pair.