Global cryptocurrencies are unbacked and have high transaction cost incurred by global consensus. In contrast, grassroots cryptocurrencies are backed by the goods and services of their issuers -- any person, natural or legal -- and have no transaction cost beyond operating a smartphone. Liquidity in grassroots cryptocurrencies arises from mutual credit via coin exchange among issuers. However, as grassroots coins are redeemable 1-for-1 against any other grassroots coin, the credit-forming exchange must also be 1-for-1, lest prompt redemption after exchange would leave the parties with undue profit or loss. Thus, grassroots coins are incongruent with liquidity through interest-bearing credit. Here we introduce grassroots bonds, which extend grassroots coins with a maturity date, reframing grassroots coins -- cash -- as mature grassroots bonds. Bond redemption generalises coin redemption, allowing the lending of liquid coins in exchange for interest-bearing future-maturity bonds. We show that digital social contracts -- voluntary agreements among persons, specified, fulfilled, and enforced digitally -- can express the full gamut of financial instruments as the voluntary swap of grassroots bonds, including credit lines, loans, sale of debt, forward contracts, options, and escrow-based instruments, and that classical liquidity ratios are applicable just as well to grassroots bonds. The formal specification presented here was used by AI to derive a working implementation of grassroots bonds in GLP, a concurrent logic programming language implemented in Dart for smartphone deployment. The implementation is illustrated by a running multiagent village market scenario, also implemented in GLP by AI.

翻译：全球加密货币缺乏背书，且因全球共识机制而产生高昂交易成本。相比之下，草根加密货币由其发行者（任何自然人或法人）提供的商品与服务背书，除智能手机操作外不产生交易成本。草根加密货币的流动性源于发行者之间通过代币交换形成的相互信用。然而，由于草根代币可按1:1比率兑换任何其他草根代币，信用形成的交换也必须遵循1:1比率，否则交换后立即赎回将导致交易方获得不当收益或损失。因此，草根代币与生息信用产生的流动性存在内在矛盾。本文提出草根债券，通过引入到期日扩展草根代币体系，将草根代币（现金）重新定义为已到期的草根债券。债券赎回机制推广了代币赎回功能，允许以流动性代币交换生息的未来到期债券。我们证明数字社会契约（人与人之间自愿达成、通过数字化方式约定、履行和执行的协议）能够以草根债券的自愿互换形式表达全部金融工具，包括信用额度、贷款、债务出售、远期合约、期权及基于第三方托管的金融工具，且经典流动性比率同样适用于草根债券。本文提出的形式化规范已被人工智能用于在GLP中推导出可运行的草根债券实现方案——GLP是一种采用Dart语言开发、面向智能手机部署的并发逻辑编程语言。该实现通过一个持续运行的多智能体乡村市场场景进行演示，该场景同样由人工智能在GLP中实现。