Smart Contracts
Intermediate
What is
Programmable IOU?
A digital bearer instrument on blockchain that encodes not just a payment obligation, but conditions under which it can be redeemed — a Note with an acceptance predicate.
A Programmable IOU is a payment commitment where the redemption conditions are encoded in the instrument itself, not managed off-chain. On Ergo, this is implemented as a Note box with an acceptance predicate in its spending script. Unlike a traditional IOU (a promise to pay), a Programmable IOU is enforced by the blockchain — the issuer cannot refuse redemption if conditions are met, and the holder cannot redeem until conditions are satisfied. This primitive is fundamental to agent economy applications where payments must be contingent on verifiable task completion.
Key Points
- Encodes both the payment amount AND the redemption conditions
- Conditions are on-chain in ErgoScript — no off-chain enforcement needed
- Bearer instrument: transferable, redeemable by anyone meeting conditions
- Differs from escrow: no third party, no separate dispute mechanism
- Backed by a Reserve — collateral is locked until Note is redeemed or expired
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Frequently Asked Questions
Questions about Programmable IOU
Common questions about this topic
Is Ergo a good investment?
This is not financial advice. Ergo has strong fundamentals: fair launch (no VC dump risk), innovative technology (eUTXO, Sigma Protocols, NiPoPoWs), active development, and a cypherpunk ethos. It's a smaller market cap project with higher risk/reward than established chains. Research thoroughly, understand the technology, and never invest more than you can afford to lose.
Comparison
Getting Started
How to get started with Ergo?
Start by getting a wallet (Nautilus for browser, Terminus for mobile). Back up your seed phrase securely offline. Get some ERG from an exchange (Gate.io, KuCoin) or DEX (Spectrum). Make a test transaction. Then explore: try DeFi on Spectrum, check out NFTs, or dive into the technology if you're a builder.
How-to
Getting Started
What can I do with Ergo?
Ergo supports a full ecosystem: trade on Spectrum DEX, use SigmaUSD stablecoin, mix transactions with ErgoMixer, collect NFTs on SkyHarbor, mine with GPUs, lend/borrow on DuckPools, bridge to other chains via Rosen, and build dApps with ErgoScript. It's a complete platform for decentralized finance and applications.
Explainer
Getting Started
What are NiPoPoWs and why do they matter?
NiPoPoWs (Non-Interactive Proofs of Proof-of-Work) are cryptographic proofs that compress blockchain history. Instead of downloading gigabytes of blocks, light clients can verify the chain with just kilobytes of data. This enables true trustless light wallets, efficient cross-chain bridges, and sidechains - all without trusting third parties.
Explainer
Technology