Money is trust. SolidPay makes it routable.

SolidPay revives Ryan Fugger's original Ripple (2004) — bilateral credit lines and payments routed through chains of trust — with Solid ideas: every user is a URI, every transition is hash-chained, and (v1) signatures via did:nostr. No blockchain, no token, no consensus, no bank in the middle.

Landing page: https://jss.live/solidpay/ · Spec: https://jss.live/solidpay/docs/spec/ · Roadmap: docs/roadmap.md

git clone https://github.com/JavaScriptSolidServer/solidpay
cd solidpay
node server.js
# solidpay node listening on port 3480 → open http://localhost:3480

One dependency — @noble/curves for BIP-340 signature verification — on plain Node.js ≥ 20. Behind a proxy:

PUBLIC_URL=https://testnet.solidpay.org PORT=3480 DATA=/var/solidpay node server.js

Open the app, create an account (you become <origin>/u/you#me — a URI that dereferences), extend a friend some credit, and pay through the graph: the route previews live before you commit.

• Trustline — one-way credit: "you may owe me up to 500 USD." Only the creditor creates, resizes, or removes it.
• Payment — BFS-routed through unused credit; every hop rides a grant its next node already made, so intermediaries need no per-payment consent. Multi-hop payments settle atomically. Owed-to-you credit spends with no trustline at all — paying back clears debt first.
• Settle — IOUs clear out-of-band; the creditor records repayment.
• Ledger — every transition hash-chained (RFC 8785 canonical JSON + SHA-256); GET /api/log/verify re-derives the whole chain, and so can you.
• Signed transitions (level 1) — a transition is a nostr event (kinds 8801–8804, content = canonical intent, BIP-340 sig) submitted at POST /api/tx; the signature is the authentication. did:nostr agents self-sign; password accounts are custodially signed with custody disclosed in their profile document. log/verify audits authorship end to end.

Books are one signed number per pair+currency — the two directions are the same number negated, so they cannot desync. All arithmetic is integer micro-units; no float drift.

server.js         the node: HTTP API + accounts + nostr auth + UI serving
lib/engine.js     the ledger engine (pure model + transitions)
lib/ui.js         the product UI (one server-rendered document)
docs/spec/        the protocol spec (Editor's Draft, HTML) + pointer md
docs/roadmap.md   v0 testnet → v1 signatures → v2 federation → v3 anchoring
test/             engine units + full-HTTP integration (npm test)
index.html        the landing page (GitHub Pages)

Proven first as the ripple plugin for JavaScript Solid Server (which remains the JSS adapter of this design), specified as webcontracts trustline.v1, and named for solidpay.org — an idea from 2018, an engine from 2026.

MIT