The term blockchain carries a lot of hype, but it is sometimes difficult to understand the full meaning. Blockchain, originally block chain, was coined to describe Bitcoin’s data structure after its launch in 2009. The name describes a chain of blocks, while each block includes transactions or updates to a…

An exotic financial product category meets Bitcoin — When the Chicago Mercantile Exchange (CME) launched the first Bitcoin futures contract in December 2017, it was a big step for the crypto industry. For the first time, a cryptoasset would be available as a commodity that could be traded via futures at the CME. So what are futures? A futures contract is a…

Intro to sharding and cross-shard trust — The challenges of scaling blockchains are well documented. The most successful blockchains in operation today form a linear chain, where each block or update references the previous. Every node on the network stores a complete copy of the ledger history. The singular chain model works extremely well at keeping the…

How developers are minimizing overhead — Blockchains keep the entire world on the same page. As each block is minted, a new ledger state supersedes prior states. Consensus mechanisms work to ensure that the state is agreed on by the wider community. In a well designed system, incentives ensure immutability. After enough time has elapsed, the…

A new kind of mixing service on Bitcoin — Fungibility is a key property that we demand from our currency. I’ve written on the relationship between privacy and fungibility before, and believe that it’s critical to get this right to lay the foundation for the future financial system. …

Getting more from less — In early May 2019, Pieter Wuille, a prolific Bitcoin Core contributor from Blockstream, quietly introduced a pair of BIPs (Bitcoin Improvement Proposals) that describe a new address scheme called Taproot. The proposals build on the Schnorr signature and Scriptless Scripts work that I discussed in prior posts and provide the…

A different kind of smart contract — In a recent post, I discussed Schnorr signatures. Schnorr signatures represent a new way to sign and verify transactions that have some surprisingly powerful properties. Schnorr signatures are smaller than ECDSA and can be combined, known as signature aggregation. …

Improving Bitcoin’s privacy and scalability — Back in September 2013, an anonymous author wrote a bitcointalk.org post suggesting there may be ways to improve privacy and scalability by aggregating or combining signatures. Multiple inputs can share a signature authorizing the collective movement of the coins. …

The Network Layer — Background In an earlier post, I discussed what it means to have privacy on the blockchain. Obscuring the sender, recipient and the amounts on the chain with cryptography go a long way in providing much needed privacy to the users. The blockchain is a very public and permanent record of transactions…