A single, long-dormant string of code, hidden deep within the original Bitcoin stack, can introduce a suite of new functionality that could potentially see the Bitcoin network rival Ethereum in terms of decentralized finance (DeFi) activity. The upgrade is called “OP_CAT” (short for operation code concatenate) and refers to a few simple lines of code originally introduced by Satoshi Nakamoto. This code was part of Bitcoin’s initial scripting system and effectively increased Bitcoin’s transaction utility and expanded the variety of operations users could perform with Bitcoin. However, Nakamoto …