I've been building an oracle protocol called SLO (Sovereign Lightning Oracle) that lets anyone buy signed, verifiable price data by paying a Lightning invoice. No API keys, no accounts — just sats and cryptographic proof. Trust math, not middlemen.
The latest addition, live on mainnet, is a EUR/USD oracle that pulls rates from the European Central Bank, Bank of Canada, Reserve Bank of Australia, Norges Bank, and the Czech National Bank, plus Kraken and Bitstamp as live forex sources. Central bank rates that aren't published directly as EUR/USD are derived via cross-rate math — for example, EUR/USD from Bank of Canada is computed as EUR/CAD ÷ USD/CAD.
How it worksHow it works
You hit the endpoint, get a 402, pay 10 sats, and receive a JSON response with the price and a secp256k1 signature over a canonical message. You can independently verify the signature — no trust required beyond the math.
curl -v http://104.197.109.246:8080/oracle/eurusdThe response looks like:
{
"domain": "EURUSD",
"canonical": "v1|EURUSD|1.18620|USD|5|...|ecb,bankofcanada,rba,norgesbank,cnb,kraken,bitstamp|median",
"signature": "...",
"pubkey": "..."
}Seven sources, four continents, one median. Signed and delivered for 10 sats.
What else is liveWhat else is live
EUR/USD is the fourth oracle on SLO. The full lineup:
| Endpoint | Price | Sources |
| BTC/USD spot | 10 sats | 9 exchanges (Coinbase, Kraken, Bitstamp, Gemini, Bitfinex, Binance, Binance US, OKX, Gate.io) |
| BTC/USD VWAP | 20 sats | Coinbase, Kraken |
| ETH/USD spot | 10 sats | 5 exchanges |
| EUR/USD spot | 10 sats | 5 central banks + 2 exchanges |
| BTC/USD DLC attestation | 1000 sats | 9 exchanges, Schnorr-signed hourly |
The DLC oracle is new too — hourly Schnorr attestations with digit decomposition for non-custodial Bitcoin derivatives. Announcements with nonce commitments are published 24 hours ahead for free. As far as I can tell, this is the first production DLC oracle on Bitcoin mainnet.
Why payment instead of freeWhy payment instead of free
Most oracles are free, which means someone else is paying for them — and that someone has interests that may not align with yours. SLO flips this: you pay per query, every response is signed, and if the data is bad you stop paying. The economic feedback loop replaces governance.
It also means any machine with a Lightning wallet can buy verified data. No OAuth, no API keys, no terms of service. We built an MCP server so Claude can query the oracles directly — it pays 10 sats per query from a connected Lightning wallet.
LinksLinks
- GitHub: https://github.com/jonathanbulkeley/sovereign-lightning-oracle
- All endpoints are live on Bitcoin mainnet right now
- L402 protocol (Lightning Labs): https://github.com/lightninglabs/L402
Happy to answer questions about the architecture, the central bank rate derivation, or the DLC implementation.