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Routstr — Decentralized AI powered by Bitcoin and Nostr

Cashu

Cashu

— 4 min read
Routstr — Decentralized AI powered by Bitcoin and Nostr

Routstr lets you pay for AI with Bitcoin, per request, using Cashu eCash. Point your existing OpenAI-compatible client to a Routstr node, pass a token, get answers. No signups, no credit cards, no KYC.

The problem (why this matters)

  • Gatekeepers everywhere: Access to powerful models lives behind platforms, accounts, and opaque approvals. There’s no open market where anyone can sell capacity and anyone can buy it.
  • No true micropayments: Today it’s monthly plans, prepayments, and thresholds. You can’t easily pay a few sats for a single call.
  • Friction + doxxing: Accounts, cards, KYC. Your usage is linked to identity. Builders lose users at signup. Users lose privacy at checkout.
  • Custodial choke points: Centralized billing concentrates risk and gatekeeping. If you’re outside “supported regions,” you’re out of luck.

The fix (what Routstr is)

Routstr is a decentralized network of nodes that sit between your app and any OpenAI-compatible provider. It turns AI usage into a sats-denominated, pay-as-you-go flow using the Cashu eCash protocol.

  • Pay with eCash (Cashu): Send bearer tokens backed by Bitcoin (via Lightning mints). It’s instant, private, and made for tiny payments.
  • Drop-in for OpenAI clients: Keep your SDKs. Just change base_url to a Routstr node and pass a key/token.
  • Permissionless supply: Anyone can run a node, set pricing, and publish presence via Nostr. Clients discover and route.
  • Privacy with eCash + Tor: eCash is unlinkable. And with optional Onion endpoints you are protected. You don’t need an account to try a model.
  • No vendor lock-in: The open-source protocol allows you to seamlessly switch between Routstr nodes as you don't have an account anyway.
  • Protected by the Nostr social graph: Nostr allows our users to discover and find information on good and bad Routstr providers.

How it works (30 seconds)

  1. You get a Cashu token (think: digital cash IOU you can hand to anyone).
  2. Your client sends an AI request to a Routstr node with either:
    • a Cashu token directly as the Authorization header, or
    • a Routstr API key backed by a prior deposit.
  3. The node verifies and redeems the token with a Cashu mint, tracks your balance, forwards your request upstream, and returns the response.
  4. The exact cost in sats is deducted based on the model and tokens used. You can withdraw remaining balance as eCash.

Note: Per-request “send token in, get change back” headers are on the roadmap; today you can already use a Cashu token directly or a pre-funded API key.

Why eCash (Cashu)?

  • Micropayments that feel like cash: No card rails, no minimums, no chargebacks.
  • Instant settlement: Backed by Lightning via mints.
  • Privacy: Bearer tokens are unlinkable by default.

Who is this for?

  • Bitcoiners who want sats in/sats out AI.
  • AI builders who hate signup funnels and want global reach and lower churn.
  • Node operators/resellers who want to sell AI capacity with custom pricing and margins.
  • Privacy-minded users who don’t want accounts for every experiment.

What can you connect to?

Anything that speaks the OpenAI API format (chat completions today; more endpoints expanding). Routstr forwards the request, tracks usage, and handles billing. Models and pricing are configurable and can auto-update.

Using it (keep your existing client)

Python example (works with the official OpenAI SDK):

from openai import OpenAI

client = OpenAI(
    api_key="cashuAeyJ0..." or "sk-...",  # Cashu token or Routstr API key
    base_url="https://api.routstr.com/v1"  # or any other node url
)

resp = client.chat.completions.create(
    model="qwen/qwen3-max",
    messages=[{"role": "user", "content": "Hello!"}],
)

print(resp.choices[0].message.content)

Command-line with curl:

curl https://your-routstr-node.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cashuAeyJ0..." \
  -d '{
    "model": "openai/gpt-5",
    "messages": [{"role": "user", "content": "Hello"}]
  }'

Run your own node (become the market)

Spin up with Docker, point to your upstream provider, and choose Cashu mints:

docker run -d \
  --name routstr \
  -p 8000:8000 \
  -e UPSTREAM_BASE_URL=https://api.openai.com/v1 \
  -e UPSTREAM_API_KEY=sk-... \
  -e CASHU_MINTS=https://mint.minibits.cash/Bitcoin \
  -e ADMIN_PASSWORD=strong-dashboard-password \
  ghcr.io/routstr/core:latest

Then check: curl http://localhost:8000/v1/info

Optional: publish your node on Nostr, enable Tor, set your own model list and pricing. See docs in docs/getting-started/.

FAQs

  • Is this only for OpenAI? No. It’s for any OpenAI-compatible upstream (Anthropic via adapters, open models, etc.). You control the upstream and models.
  • Do I need an account? No. You can supply a Cashu token directly as your credential. Nodes may also offer pre-funded API keys.
  • How are costs calculated? Model-based token pricing (USD → sats) with transparent fees. Each response includes usage and cost headers.
  • Can I withdraw? Yes. Remaining balance can be withdrawn back to eCash.
  • What about per-request change? Header-based per-request flow is planned; direct token usage and pre-funded keys work today.

Try it now!

  • Go to https://chat.routstr.com/ to start chatting with AI.
  • Connect a public node (or run your own) and pay with sats.
  • Point your existing OpenAI client to https://<public-node>/v1, pass a Cashu token and periodically top-up here.
  • If you operate infra, set pricing and list your node on Nostr. Welcome to the permissionless AI marketplace.

This article is a guest post by Routstr.

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