Senior Backend Engineer
Summary
Senior backend engineer owning core services and APIs end to end for a social investing platform — social feeds, paper/live/copy trading. Day to day: build TypeScript/Node.js services, WebSockets and HTTP APIs, Kafka event pipelines, and PostgreSQL queries, plus Redis/Valkey caching, PR reviews, and incident debugging.
Salary: $120,000 – $125,000 per year
About the role
We're looking for a Backend Engineer to own core services and APIs end to end. You'll design, build, and run the systems that power social feeds, paper trading, live trading, and copy trading — from WebSockets and HTTP APIs to Kafka pipelines and Redis/Valkey caches. This is a hands-on role: you'll write production code, review PRs, debug incidents, and shape how we build for the long term.
Key responsibilities
Design, implement, and maintain backend APIs and background workers
Own services across social, paper trading, live trading, and copy trading
Write and review PostgreSQL queries — performance and correctness matter
Produce and consume Kafka events with solid retries and idempotency
Keep paper, live, and copy trading cleanly separated: balances, P&L, and trader payouts
Build paper trading: simulated positions on live prices, including SL/TP and liquidation
Integrate live trading with a non-custodial perp DEX — immutable trade records (no edits, no deletes)
Review pull requests, debug production issues, and ship changes that are safe at scale
Partner with mobile and product engineers on clear, stable API contracts
About you
4+ years building backend services in production
Strong TypeScript/Node.js
Deep SQL and PostgreSQL — comfortable owning schema and query performance
Event-driven systems in anger (Kafka or similar)
HTTP API design and operation you'd be happy to put your name on
Ownership mindset: debugging, deployments, on-call — you don't disappear after merge
Ability to extend existing code without inventing a parallel pattern every time
About us
We're a US-based fintech startup — five years in, profitable, and entering a major Series A with institutional investors. Our product is social investing: traders build portfolios, share ideas, and earn when others follow their performance. We're top-three globally in our category, with a strong focus on crypto today and room to grow. The team is fully remote, spread across the US and Australia, with competitive cash compensation and meaningful stock options. You'll work with people who care about shipping reliable systems, not slide decks.