APIs & Rates

The Nexus Exchange is API-first. Everything a trader can do — fund an account, place and cancel orders, query positions, stream the order book — is available over REST and WebSocket. The web frontend is a read-only view; programmatic access is the primary interface.

Base URL

https://exchange.nexus.xyz/api/exchange

This is the testnet preview gateway. The machine-readable OpenAPI specification is served at /openapi.json and versioned at nexus-xyz/nexus-exchange-api; releases are tracked on GitHub Releases.

Authentication model

There are two credential types:

1. Session token (Bearer). Created by signing a fixed message with your Ethereum wallet (EIP-191). Used only to create and manage API keys — never for trading. Expires after 24 hours.
2. API key (HMAC). A key_id + secret pair. Every trading and account request is signed with HMAC-SHA256 over a canonical request string. The secret is shown once at creation and cannot be retrieved later.

1. POST /auth/login   (wallet signature)        → session Bearer token
2. POST /keys         (Bearer)                   → API key_id + secret
3. sign each request  (HMAC over canonical str)  → trade

See the Quickstart for the full flow with runnable cURL.

CCXT

CCXT-compatible read endpoints are available today (markets, tickers, order book, trades, balances, positions), tagged in the OpenAPI spec. Broader CCXT support, including order placement, is planned.

Reference

• Quickstart: Your First Trade
• REST API Reference
• WebSocket API Reference
• Rate & Connection Limits

Status: testnet preview. Credentials, sessions, and rate-limit state are not yet durable across gateway restarts — treat API keys as re-creatable. Production hardening is in progress.