simplebond

simplebond is a TypeScript toolkit (the original sketch mentioned Python; this repo is TS-only) for modelling programmable fixed-income (“digital bond”) issuance and settlement on Bitcoin-aligned rails. It aligns with covenant-without-soft-fork research (PIPEs v2: witness encryption for conditional signing, IACR 2026/186, Delving Bitcoin; PRECOP: Simplicity-style templates + atomic swaps, BitcoinWorldTrustFoundation/precop, press overview)—but only ships logic that belongs in audited TypeScript today. See Project brief ↔ this repository (below) for the exact exports.

Treat this as an education / integration sketch: not a production wallet, indexer, or audited Elements deployment.

Simplicity roadmap context (developer tooling & interpreter evolution) stays authoritative at docs.simplicity-lang.org/resources/roadmap; behavioural nuance belongs in Simplicity execution model.

Secondary reporting on PIPEs v2 (plain-language summaries) occasionally appears via outlets such as Blockspace—defer to primary sources (eprint/Delving Bitcoin) for protocol detail.

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Project brief ↔ this repository

Idea-doc requirement	Implemented as
Bond terms → programmable UTXO / Simplicity-aligned plan	buildBondCovenantIr (JSON covenant IR) + compileBondToTaproot (CLTV Taproot leaf scripts + bcrt1p; no shipped .simp/bytecode).
Client-side validation without broadcasting	validateSettlementTrace, buildCouponSchedule / couponAmountForPeriodSats (bigint).
Atomic settlement (HTLC + adaptor-style hooks)	htlcSha256, htlcHash160, randomPreimage32, adaptorCommitmentPointXOnly (wallet/MuSig2/PSBT wiring out of scope).
~30 day bond: issue, pay coupons, redeem principal	simulateThirtyDayRegtestLifecycle, npm run demo (offline JSON narration; npm run demo:run if dist/ already built).

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Install

Requires Node ≥ 18.

npm install
npm run ci       # vitest + `rm -rf dist && tsc`
npm run demo     # offline 30‑day narration (rebuilds dist)
npm run demo:run # optional: rerun demo only when dist/ is fresh

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Capabilities vs. aspirations

API	Ship status
buildCouponSchedule, couponAmountForPeriodSats, buildBondCovenantIr	Stable TypeScript. Bigint APR math + covenant manifest.
compileBondToTaproot, payments.p2tr	Regtest/demo Script. Mirrors IR branch count one-for-one against Taproot leaf cardinality.
validateSettlementTrace	Pure logic. Suitable for dashboards & bondholder proofs without broadcasting.
Atomic settlement primitives	Scaffolding. Hash/link + curve point derivation only—still need PSBT/MuSig2 choreography from your wallet stack.
Full Simplicity→UTXO codegen	Out of repo scope unless you bolt on hal-simplicity/Liquid infra; IR exists to interoperate instead of pretending we emit bytecode.

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Regtest storytelling (offline)

Issue + validate + narrate programmatically:

import {
  simulateThirtyDayRegtestLifecycle,
  summarizeRegtestLifecycleJson,
} from 'simplebond';

const run = simulateThirtyDayRegtestLifecycle(/* optional issuanceHeight */);
console.assert(run.clientValidation.ok);

console.log(JSON.stringify(run.covenantIr, (_, v) => (typeof v === 'bigint' ? v.toString() : v)));
console.log(summarizeRegtestLifecycleJson());

BLOCKS_PER_DAY defaults to 144 (~10 min blocks) purely for exposition; tweak couponPeriodBlocks/gracePeriodBlocksAfterCouponDue for your simulator cadence.

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Safety checklist

1. Demo fixture private keys (src/demo/thirtyDayDemonstration.ts) are textbook placeholders—never mainnet funds.
2. Choose an internal Taproot key whose discrete log stays unknown if you insist on disabling key spends; blindly reusing signer pubkeys defeats that property.
3. PIPEs v2 is early-stage cryptography: follow the ePrint discussion and Delving Bitcoin design thread for witness-encryption assumptions, verifier economics, and evolving ciphertext footprints (public summaries sometimes cite coarse storage estimates that are meant to tighten over time—not modeled in this repo).

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npm scripts

Script	Behaviour
npm test	vitest (compiler/IR parity, validators, hashing, adaptor determinism, lifecycle JSON).
npm run ci	npm test then npm run build (one-shot green check).
npm run build	Cleans dist/, emits ESM+CJS-compatible library output (tsc).
npm run demo	Rebuild (rm -rf dist && tsc) then runs dist/demo/regtestLifecycle.js.
npm run demo:run	Runs the demo CLI against existing dist/ only (fail-fast if not built).

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License

MIT.

Contact Info

Telegram: @AuraTerminal