Bitcoin'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.

Ethereum Calldata Repricing and Layer-2 Economics

Coin Age: The Metric That Shaped Early Proof-of-Stake

Ethereum Gasper Slashing: Attestation Rules and Penalties

Bitcoin Erlay: Peer Selection and Mempool Privacy

Bitcoin 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.

Bitcoin 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.

Bitcoin'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.

Stratum 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.

Bitcoin'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.

Stratum V2 Job Negotiation: Miners Reclaim Block Templates

Stratum V2 lets miners build their own block templates, stripping pool operators of the power to quietly drop specific transactions. The mechanics, examined.

Ethereum's Fork Choice Rule: Tie-Breaking in LMD-GHOST

When two Ethereum blocks carry identical attestation weight, a deterministic root-hash rule decides the winner, the mechanic explained, with a worked example.

Bitcoin 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.

Ethereum State Reverts on Out-of-Gas Sub-Calls

A failed inner call reverts only its own frame, the outer transaction can still succeed. The mechanic, the 63/64 rule, and what silent failure costs you.

Stratum V2: Bitcoin Miners Reclaim Block Template Control

Stratum V2 separates transaction selection from hashrate contribution, giving individual miners editorial control over what their machines actually confirm.

Ethereum Gasper: Proposer Slashing Explained

Gasper slashes validators who sign two blocks at the same slot. Mechanism, correlation penalty math, and a concrete worked example.

Bitcoin'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.

Ethereum's Fork Choice Rule and Late Attestations

How Ethereum's LMD-GHOST handles attestations that arrive after the voting deadline, and what it means for chain security.

Ethereum Blob Data: Why Smart Contracts Can't Read It

Blob transactions cut rollup data costs sharply, but the EVM only ever sees a 48-byte commitment. The mechanical reason is deliberate, and worth understanding.

Ethereum Verkle Trees and State Proof Economics

Verkle trees cut Ethereum witness sizes from megabytes to ~150 KB, reshaping costs for node operators, validators, and proof generators.

Bitcoin 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.

SIGHASH_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.

Ethereum EIP Types: Informational vs Core Explained

The EIP process splits proposals into distinct types for good reason. Learn how Informational and Core EIPs differ and why that distinction shapes Ethereum.

Bitcoin'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.

Gasper Attestation Timing: Slot Weights Explained

Gasper cuts attestation rewards sharply with each slot of delay. The precise mechanic, the three scoring components, and worked numbers.

Bitcoin Covenant Proposals: Miner Trust and Recursion

CTV, CSFS, and MATT draw the line between allowed and forbidden differently, and each encodes a distinct bet on miner honesty and script recursion.

Ethereum Inclusion Lists and Censorship Resistance

How Ethereum's inclusion list auction design limits builder censorship power, with concrete mechanics and honest caveats about what it can and can't fix.

Bitcoin Transaction Pinning and Lightning Force-Closes

Transaction pinning can trap Lightning Network force-closes at uncompetitive fee rates, burning timelocks. The mechanics, the stakes, and the fixes in progress.

Ethereum Blob Fee Burns and Validator Rewards Explained

Blob transaction fees burn separately from execution gas. Here's exactly how that splits validator accounting during L2 congestion spikes.

MEV: Public Mempools vs Private Transaction Relays

Your transaction's route, public mempool or private relay, determines who can extract value from it and how much. The mechanics, the tradeoffs, the gaps.

Ethereum's Gasper Consensus: Casper FFG and LMD-GHOST

Gasper powers Ethereum's finality. Learn how Casper FFG and LMD-GHOST fork choice combine to keep the chain safe and live.

Bitcoin Erlay Fanout Phase: Peer Selection Explained

Erlay's fanout phase pushes transactions to a randomized peer subset, not the whole network. A close look at the mechanism, its privacy logic, and its limits.