Sats as signal.
No KYC,
no custody.

Sign one Bitcoin message. Any app can verify you’ve kept N sats unspent for N days in one API call. No account. No permission. Honest users pay nothing — attackers pay real opportunity cost.

Create a proof →Try the API Integrate

✓ BIP-322✓ Nostr kind 30078✓ offline-verifiable✓ MIT / CC-BY-4.0

bash ⋅ attest.ochk.io/api/check

cache60srate60/minauthnoneaddr—

§ what are you solving?

Pick the path that matches your problem.

Every row points at a real integration that exists today — guide, package, and working code. If none of them match, read how OrangeCheck compares to alternatives and decide from there.

[01]Running a forum or comments section
Bot spam, drive-by throwaways, and Sybil accounts undermining every thread. Require a small OC attestation before a user can post.
// @orangecheck/gate · 10 lines
→ Gate a route
[02]Running an airdrop or token distribution
Sybil farms that split one wallet into ten thousand claim addresses. Filter candidate addresses by min_sats × min_days before distribution.
// @orangecheck/airdrop-gate · bulk CLI
→ Filter an airdrop
[03]Operating a Nostr relay
Unbounded spam from unproofed npubs — impossible to moderate at scale. Accept posts only from npubs with a verified OrangeCheck attestation.
// @orangecheck/relay-filter · Strfry plugin
→ Filter a relay
[04]Building a web app that needs identity
Passwords, magic links, and email auth — all leak, all scale poorly. Sign in with a Bitcoin message. The address is the account.
// /api/auth/* · 30-day session
→ Sign in with Bitcoin
[05]Running on-chain governance or DAO votes
Sybil governance attacks where one voter controls many "holders". Weight votes by OC score — log(sats) × days rewards long-term skin.
// score_v0 · offline-verifiable
→ Weight by score
[06]None of the above — you want full control
No external dependency on ochk.io, your own relays, your own Postgres. Clone the stack, point the SDK at your instance. Same protocol, your infra.
// 3 env vars · any Postgres 14+
→ Self-host the verifier

§ how it works

Three steps. One primitive. Fits on a napkin.

[01]SIGN
One canonical message. BIP-322 signature from any Bitcoin wallet. No transaction, no spending — funds never leave your control.
// sha256(msg) → attestation_id
[02]PUBLISH
Drop the proof on Nostr, embed it on your site, share a short URL. Self-contained JSON that anyone can verify offline, forever.
// kind 30078 · parameterized replaceable
[03]VERIFY
One GET returns pass/fail plus raw metrics. No SDK. Or drop in @orangecheck/gate middleware for Express, Next, Fastify, Hono.
// GET /api/check → 200 · 60s cache

§ integrate

Same decision,
every stack.

Query the hosted API, drop in middleware, or import the SDK. Pick your poison.

curl "https://attest.ochk.io/api/check?addr=bc1q...&min_sats=100000&min_days=30"

{
  "ok": true,
  "sats": 125000,
  "days": 47,
  "score": 30.12,
  "attestation_id": "a3f5b8c2…",
  "identities": [
    { "protocol": "nostr",  "identifier": "npub1alice…" },
    { "protocol": "github", "identifier": "alice" }
  ]
}

§ ecosystem

Every piece open. Every piece optional.

Open-core. Pick the piece that fits your stack — or just curl the hosted API directly.

langpackageinstall

node
@orangecheck/sdk
Core protocol. check(), verify(), createAttestation()
node
@orangecheck/gate
HTTP middleware. Express, Next, Fastify, Hono, Workers
node
@orangecheck/react
<OcBadge>, <OcGate>, <OcChallengeButton>
node
@orangecheck/wallet-adapter
One sign() API across UniSat, Xverse, Leather, Alby
node
@orangecheck/cli
`oc` shell. check, verify, discover, challenge
node
@orangecheck/relay-filter
Sybil filter for Nostr relays. Strfry plugin included
node
@orangecheck/airdrop-gate
Filter candidates into sybil-resistant allowlists
python
orangecheck
Python SDK. Django, Flask, FastAPI

8 packages · hover a row to reveal the install command

§ pick where to start

No email. No password. No KYC.

Every page except your dashboard works without signing in. Every public API endpoint is unauthenticated. Sign in — when you want to — with one Bitcoin signature; your wallet is your login.

docs api reference protocol spec ↗discover attestations status github ↗

Sats as signal.No KYC,no custody.