Bitcoin'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.
№ 038BitcoinBitcoin'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.
№ 039BitcoinCoin 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.
№ 040BitcoinBitcoin 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.
№ 041BitcoinBitcoin 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.
№ 042BitcoinBitcoin'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.
№ 043BitcoinBitcoin's Quadratic Sighash Bug, Explained
Before SegWit, a single crafted transaction could stall nodes for minutes. The mechanism, the real attack surface, and what BIP143 actually changed.
№ 044BitcoinBitcoin Hashrate Escrow and Merged-Mined Sidechains
Hashrate escrow lets Bitcoin miners secure sidechains without a second consensus system, the exact mechanism, BIP 300 numbers, and honest caveats included.
№ 045BitcoinBitcoin's Taproot Annex: Reserved Space Explained
The Taproot annex is a reserved byte field in Bitcoin transactions, committed at signing, consensus-valid today, and blank until a future soft fork fills it.
№ 046BitcoinBitcoin Miniscript: Complex Spending Conditions Explained
Miniscript compiles human-readable Bitcoin spending policies into verifiable, non-malleable Script, concrete mechanism and a worked treasury example inside.
№ 047BitcoinSIGHASH_ANYPREVOUT and Eltoo Payment Channels
APO lets eltoo overwrite old channel states without penalty transactions or revocation archives. A concrete look at the mechanism and what blocks deployment.
№ 048BitcoinBitcoin's Dandelion Protocol and Transaction Origin Privacy
Dandelion splits Bitcoin propagation into stem and flood phases to defeat IP-to-transaction correlation. Mechanics, real tradeoffs, and deployment status.