Build with Nonlogs

Overview

External-wallet swaps

Create a customer swap using an API key with External swaps permission. Use the signed-request headers and signature format documented below for every endpoint. No CAPTCHA or browser session is required. Keep API secrets on your server, never in customer-side JavaScript.

The customer sends funds to the returned deposit address. This does not spend your NonLogs balance. Prices float until execution; estimates are not guaranteed. Normal trading fees, a 0.8% convenience fee and outgoing network charges apply. Your API account receives 50% of collected customer trading fees and 50% of the convenience fee, in the same coins, automatically. No referral link is needed; unfunded swaps and untraded refunds earn nothing. Provable self-referrals are excluded.

{"from":"BTC","to":"XMR","amount":"0.001","from_network":"bitcoin","to_network":"monero"}

{"from":"BTC","to":"XMR","amount":"0.001","from_network":"bitcoin","to_network":"monero","payout_address":"CUSTOMER_MONERO_ADDRESS","refund_address":"CUSTOMER_BITCOIN_ADDRESS","client_request_id":"8b6d7b3b-342f-4c1f-86f7-b29ef302266a"}

Amounts are decimal strings, not JSON numbers or exponent notation. Fees are denominated in the displayed asset; trade-fee entries each carry their own symbol. API timestamps are UTC ISO 8601. Funding is open for 24 hours. Deposits are processed individually using their actual amounts; confirmed and spendable payments may wait up to 12 hours for matching. Partial execution can produce both a destination payout and a source refund. Existing approval and network safety rules still apply.

Limits are account-wide across keys: initially 10 new sessions per minute and 50 unexpired funding sessions, plus shared address-pool/backlog caps and normal API request limits. Retries do not allocate another slot. A 429 includes Retry-After; 401 indicates authentication failure, 403 missing permission, 404 inaccessible swap, 422 invalid inputs or unavailable route, and 503 a pause or temporarily uncertain outcome. Pausing new creation does not stop status access, monitoring or existing obligations.

When creating a key through the credential interface, set external_swaps: true and provide the current password and a fresh authenticator code if enabled. Existing keys do not gain this permission automatically. All keys retain their existing trading permissions; enable ordinary withdrawal access only if you separately need it.

Send all four headers below. Timestamps must be within 30 seconds of server time and every hexadecimal nonce may be used only once.

Canonical payload

METHOD
PATH
TIMESTAMP
NONCE
SORTED_QUERY
BODY

Use the uppercase method, path beginning with /, query parameters sorted by key and RFC 3986 encoded, and the exact raw JSON body. Use an empty line when query or body is absent. The signature is hex(HMAC_SHA256(api_secret, payload)).

Python signing example

import hashlib, hmac, json, secrets, time
from urllib.parse import urlencode

method = "POST"
path = "/tradeuser/orders/limit"
query = {}
body = json.dumps({
    "pair": "BTC-USDT",
    "type": "LIMIT",
    "operation": "BUY",
    "quantity": "0.00100000",
    "price": "68000.00000000"
}, separators=(",", ":"))
timestamp = str(int(time.time()))
nonce = secrets.token_hex(16)
sorted_query = urlencode(sorted(query.items()), safe="~")
payload = "\n".join([method, path, timestamp, nonce, sorted_query, body])
signature = hmac.new(API_SECRET.encode(), payload.encode(), hashlib.sha256).hexdigest()

Errors and retries

Errors use a stable machine-readable code:

{"error":{"code":"invalid_signature","message":"The request signature is invalid."}}

Respect 429 and its Retry-After header. Retry read requests after temporary 503 responses. For order placement, use a persistent client_order_id UUID before retrying an uncertain client connection.