Developers
An API written by people
who have been paged.
REST for state, WebSocket for streams, FIX 4.4 for the desks that insist. Idempotency keys on every mutation and a changelog that tells you before something changes.
import { Novex } from '@novex/sdk'; const novex = new Novex({ apiKey: process.env.NOVEX_KEY }); // Post-only limit order — never crosses the spreadconst order = await novex.orders.create( { market: 'BTC-USD', side: 'buy', type: 'limit', price: 94_800.00, size: 0.25, postOnly: true, }, { idempotencyKey: crypto.randomUUID() },); console.log(order.status); // "open"Design principles
Six decisions we will not revisit
Every one of these exists because somebody on this team got woken up by its absence at a previous job.
Idempotency on every write
Every mutating endpoint accepts an idempotency key and honours it for 24 hours. Retries are safe by construction, not by convention.
90-day deprecation windows
Nothing breaks without three months of notice, a public changelog entry, and a deprecation header on every affected response.
Sequenced streams
Snapshot then deltas, with monotonic sequence ids and an explicit gap signal so your book can never silently diverge.
Honest rate limits
Token bucket, headers on every response, and a documented burst allowance. No shadow throttling.
Cursor pagination everywhere
Opaque cursors, never offsets. Your pagination cannot skip or duplicate rows when the underlying data moves.
Sandbox that matches prod
The sandbox runs the same engine build with synthetic liquidity. Behaviour differences are treated as bugs.
Reference
The endpoints you will use on day one
Full OpenAPI 3.1 specification, generated SDKs for six languages, and a Postman collection that actually stays current.
- GET
/v3/marketsListed markets, tick sizes and status - GET
/v3/markets/{id}/bookAggregated depth to any level - POST
/v3/ordersCreate an order (idempotent) - DELETE
/v3/orders/{id}Cancel by id or client id - GET
/v3/fillsFill history with cursor pagination - POST
/v3/transfersMove between accounts and wallet
600 req/min
Rate limit
100 req/s
Burst
400 per key
WS channels
Build against the sandbox tonight.
Same engine build, synthetic liquidity, no KYC required to start. Keys are issued instantly.
No minimum deposit · Cancel anytime · Available in 46 currencies