Programmability

Programmability is the degree to which a system can be directed by software rather than by manual steps. In crypto and payments, it usually describes how far money or assets can carry rules that execute automatically, for example releasing funds when goods are delivered, splitting a payment between several parties, or restricting a token to approved holders. Blockchains differ widely: Bitcoin offers a deliberately limited scripting language, while platforms such as Ethereum run general-purpose smart contracts. Banks and payment firms also offer programmability through APIs and automated rules. The idea underlies discussions of programmable money and of central bank digital currencies, where supporters cite efficiency and critics warn that conditions on how money may be spent could limit privacy and freedom. Greater programmability also means more code, and therefore more room for bugs and exploits. Also see programmable credit.