Bitcoin Script is the programming language behind every Bitcoin transaction. It locks funds with conditions and unlocks them when those conditions are met — using a stack machine that's intentionally not Turing-complete.

The Lightning Network moves Bitcoin payments off-chain using payment channels and multi-hop routing. This post explains the mechanism — how channels open, how HTLCs enable trustless routing, and where liquidity and reliability constraints live.

A subnet in Avalanche is a validator set, not a blockchain. This post explains how subnets work, how Avalanche9000 changed the model, and where the constraints live.

Polkadot parachains are sovereign blockchains that connect to a central Relay Chain for shared security. Here's how collators, paravalidators, XCM messaging, and the new Agile Coretime model actually work.

IBC (Inter-Blockchain Communication) is the protocol that lets Cosmos-based blockchains exchange tokens and data without relying on a trusted intermediary. This post maps the mechanism, the trust model, and the key constraints.

Ouroboros is Cardano's formally verified proof-of-stake consensus protocol. Here's how it selects block producers, why epochs and slots matter, and what formally verified actually means.

Solana processes thousands of transactions per second using Proof of History and parallel execution. Here's the actual mechanism behind the speed — and the trade-offs it creates.

XRP uses federated Byzantine agreement — no mining, no staking. Validators vote using trusted node lists, and finality is deterministic in 3–5 seconds. This explains the mechanism, the UNL architecture, and where the security trade-offs actually live.

Sidechains are separate blockchains connected to a main chain via a two-way bridge. They don't inherit main chain security — that's the trade-off. This post explains the mechanism, bridge security models, and why the design distinction matters.

State channels let two parties transact off-chain and settle only the final balance on-chain. The mechanism, constraints, and where this fits in the Layer 2 landscape.

Blockchain finality is the point at which a transaction becomes practically irreversible. Bitcoin achieves it probabilistically through accumulated proof of work. Ethereum now achieves it cryptoeconomically through validator attestation. Here's how the mechanism actually differs — and why the distinction matters for settlement, bridges, and infrastructure design.

Flash loans are uncollateralized DeFi loans that must be borrowed and repaid within a single transaction. The mechanism, legitimate use cases, exploit context, and constraints explained.