Blockchain
A distributed ledger replicated across a network of nodes, in which transactions are grouped into blocks and each block contains the cryptographic hash of the previous block’s header. Altering a recorded block would invalidate every later block and would require the cooperation of the network’s consensus mechanism, so the history is tamper-evident and, in practice, append-only.
- Immutability is not absolute: recent blocks can be replaced during a chain reorganisation, and on Proof-of-Work networks finality is probabilistic, growing stronger with each block added on top. On public blockchains the ledger can be read by anyone, which is what makes forensic analysis possible; privacy-oriented protocols restrict this visibility.
Related
Essays
- The Magic of Flash Loans (Part 1): Capital Was Never the Constraint
“Outside a blockchain that is not a financial product, it is a contradiction.”
- The Desk Opens on Monday
“The blockchain keeps no calendar.”
- Achilles Catches the Tortoise Where It Has to Stop
“A blockchain is still block after block, transaction after transaction.”
- What a USDT Recovery Actually Looks Like
“Common bridged versions of USDT (tokens that represent USDT on blockchains other than the native Tether-issued ones) cannot be frozen by Tether because they are not issued by Tether.”
- Welcome to Constraints
“I'll assume only an understanding of blockchains and about three or four minutes of your attention per episode (probably a better investment than the usual LinkedIn AI-digested motivational slop).”
- Guess Who? (On-chain)
“A match between the blockchain and the social network's timeline.”
- Wallet Balances
“People think blockchain investigations are about finding information.”
- A Special Demixing Case
“But what goes in and what comes out are deliberately disconnected: equal-sized chunks, shuffled together, no on-chain line you can draw from "money in" to "money out." Everyone's coins sit in one shared pool, and when a withdrawal happens the blockchain will not tell you whose deposit paid for it.”