Bitcoin Sighash Flags: What Signatures Actually Commit To
Bitcoin sighash flags control exactly which transaction fields a signature binds to, understanding them separates safe wallet code from exploitable wallet code.
№ 074EthereumEthereum Verkle Trees: Inclusion Proof Costs Explained
Verkle trees shrink validator witness data from megabytes to kilobytes per block. The mechanics, tradeoffs, and what it means for stateless clients.
№ 075BitcoinBitcoin's Taproot Annex: Protocol Extensions Explained
The Taproot annex sits consensus-valid but relay-blocked inside every Taproot input, a reserved extension point whose format and uses are still being settled.
№ 076BitcoinBitcoin's assumevalid: Script Skipping Explained
Bitcoin Core's assumevalid parameter cuts initial sync from days to hours by skipping old script checks, while still verifying proof-of-work and every UTXO.
№ 077EthereumEthereum Calldata Repricing and Layer-2 Economics
EIP-4844 and earlier calldata repricing reshaped what Layer-2 rollups pay to settle on Ethereum, the precise mechanics, the numbers, the limits.
№ 078BitcoinCoin Age: The Metric That Shaped Early Proof-of-Stake
Coin age powered the first proof-of-stake blockchains before being quietly retired. It had genuine appeal and a structural flaw that slashing eventually solved.
№ 079EthereumEthereum Gasper Slashing: Attestation Rules and Penalties
Gasper punishes double voting and surround votes with scaled ETH penalties. The math, the failure modes, and why slashing protection databases matter.
№ 080BitcoinBitcoin Erlay: Peer Selection and Mempool Privacy
Erlay cuts Bitcoin's relay bandwidth by ~84%. The peer selection logic, decided before any transaction data exists, is where the privacy argument lives.
№ 081MiningBitcoin Nonce Exhaustion and the Extra Nonce Fix
A modern ASIC sweeps 4 billion nonces in under a millisecond. The extra nonce mechanism expands the search space, here is how the architecture actually works.
№ 082BitcoinBitcoin Covenant Opcodes: Trust Assumptions Compared
OP_CTV, OP_VAULT, and CSFS enforce spending rules differently. Their trust assumptions diverge sharply, and that gap determines your real attack surface.
№ 083BitcoinBitcoin's Quadratic Hashing Bug: SegWit's Fix Explained
Bitcoin's sighash algorithm scaled as N² with input count, creating a live attack vector. The mechanics, the 2015 megatransaction, and how BIP143 closed it.
№ 084MiningStratum V2 Header-Only Mining Cuts Pool Censorship
Stratum V2's Job Negotiation mode lets miners build their own block templates, removing the pool's ability to censor transactions. The tradeoffs explained.