interface IBond.sol

IBond is a small common language for fixed-rate bonds on Ethereum. Each bond is also an ERC-20 token: a holder's balance is a transferable claim on the bond's remaining payments.

The interface makes the important facts readable in the same way on every implementation—who owes the money, which asset pays it, the denomination and dates, how much is issued or outstanding, and whether the bond is live, late, redeemable, or settled. Issuers can issue units and fund principal; holders can inspect and claim what they are owed.

More specialized behavior stays composable. Coupons, subscriptions, calls, puts, conversions, reopenings, transfer restrictions, and auctions can be added through extensions without making the base bond interface harder for wallets, protocols, and indexers to read.

This carries real issuance at market scale. An issuer can run a full corporate bond program — or the entire U.S. Treasury market — as IBond contracts and pay holders directly: the issuer or its paying agent executes each holder's claim and absorbs the gas, so coupons and maturity principal arrive without holders ever sending a transaction. The cost model prices this end to end — a reasonable cost on Ethereum mainnet and extremely cheap on a chain like Base — and the onchain bills page replays today's live Treasury bill universe contract-for-contract to show the scale is real.