Senior Backend Engineer (Node.js / TypeScript)

Job description

Responsibilities

- Market data: ingest vendor feeds, normalize instruments and symbology, and fan out to web and mobile clients over WebSockets (subscription management, snapshot + delta, conflation and throttling, slow-consumer handling, reconnect and resync); enforce entitlements (real-time vs. delayed, professional vs. non-professional).

- Order management: build the integration layer on top of the clearing firm's REST and FIX APIs — order gateway (validation, pre-trade checks, idempotent submission), order state driven by provider events, positions, realized and unrealized P&L, reconciliation against snapshots and the ledger.

- Reliable ingestion of provider webhooks and event streams: signature verification, deduplication, out-of-order handling, gap detection, replay.

- Authentication and session management, account lifecycle, entitlements, and billing hooks.

- Identify gaps in vendor APIs and propose solutions (build, work around, or escalate to the vendor). Design for graceful degradation when upstream feeds are unavailable.

Requirements

- 5+ years of backend development with a focus on distributed, event-driven systems; 3+ in Node.js / TypeScript, including the runtime under load (event loop, stream backpressure, memory/GC, scaling stateful connections).

- Has built and operated a high fan-out real-time system serving many concurrent clients and can describe it in numbers (connections, messages per second, p99 latency).

- Practical understanding of message ordering, duplicate delivery, idempotency, retries, backpressure, replay, and failure recovery.

- Experience running production systems that handle financial transactions; experience with monitoring, structured logging, tracing, and incident investigation.

- Experience with AWS (containers, IAM, managed messaging/streaming) and Redis; infrastructure-as-code.

- Strong automated-testing practices (unit, integration, end-to-end).

- Occasional traveling to the USA might be needed.

Nice to have

- Brokerage, clearing, custody, or market-data provider integrations; knowledge of equity and options order lifecycles (submission, partial fills, cancel/replace, rejection).

- FIX, financial instrument symbology, exchange connectivity.

- PostgreSQL, Redis, and a time-series or analytical store.

- Systems handling monetary values, audit trails, reconciliation, regulatory requirements.

- Futures, crypto, or prediction-market platforms.