Sr. Software Engineer II, Platform/API

As a Sr. Software Engineer II on the Activation & Onboarding squad at NinjaTrader, you own the service layer that takes prospective traders from initial sign-up to funded and trading. You'll design, deploy, and operate a modern Node.js and TypeScript service architecture, managing event-driven orchestration, background processing, third-party integrations, and the reliability engineering that keeps multi-step flows dependable at scale. Your work directly impacts account approvals, time-to-funding, and how quickly the platform can open to new markets.

What you'll do

• Design, develop, and maintain Node.js and TypeScript services that orchestrate account creation, identity verification, agreement handling, and funding hand-off
• Build the event-driven and asynchronous processing that moves applicant and verification data between internal systems and external providers, using message queues, pub/sub, and streaming pipelines
• Own correctness in long-running, multi-step flows: ensure idempotency, retry and resumption semantics, deduplication, and reconciliation for steps that cannot simply be replayed
• Design and evolve the background task runners and job orchestration that drive downstream account creation and decisioning
• Build the operational tooling the squad needs when an application stalls mid-flow: inspection of in-flight state, targeted replay, and safe requeue
• Define service-level expectations for the flows you own, along with the monitoring and alerting that surface provider failures and applicant drop-off before a customer reports them
• Design and implement scalable, resilient service architecture using cloud-based infrastructure such as Google Cloud Platform and Kubernetes
• Extend onboarding to new markets, brands, and account types, keeping jurisdiction-specific behavior configurable rather than forked
• Coordinate technical direction with engineers on adjacent squads whose systems consume your events, and coach engineers at the Sr. Software Engineer I level through design review and pairing

What you bring

• 6+ years of professional software development experience building and operating backend services in production
• A Bachelor's or Master's degree in Computer Science, Software Engineering, or a related field (or equivalent practical experience)
• Deep Node.js and TypeScript expertise, with strong command of asynchronous patterns, concurrency, and backpressure
• Proven production experience with event-driven architecture, including delivery guarantees and poison-message handling, on message queues, pub/sub, or streaming platforms such as Kafka or Google Cloud Pub/Sub
• Demonstrated experience building idempotent, resumable workflows that stay correct under retries, partial failure, and out-of-order delivery
• Strong SQL and schema design, plus hands-on experience with Docker, Kubernetes, and a major cloud platform
• Demonstrated use of AI coding agents (Codex, Cursor, Claude Code) as a standard part of your engineering workflow, with the judgment to review and validate AI-assisted code before it ships
• Excellent communication and the ownership to run a workstream end to end: design, implement, test, deploy, operate on-call, and iterate

Nice to have

• Experience with identity verification, KYC/AML, or fraud and risk decisioning systems
• Experience in fintech, trading, or brokerage, particularly in a regulated financial services environment
• Experience integrating third-party providers whose contracts and failure modes you do not control
• Familiarity with workflow or saga orchestration frameworks, and with feature flagging platforms such as Statsig
• Passion for futures, derivatives, and trading technologies

What we offer

• Salary of $140,000-$190,000 USD plus an annual target bonus of 12% (based 50% on individual performance and 50% on company/team performance)
• 401k plan with 3.5% company match
• 18 days annual paid time off, plus 7 paid holidays and 5 conditional holidays annually
• 1 service day annually
• Paid parental bonding leave
• Health, vision, and dental coverage
• Life and disability insurance covered 100% by NinjaTrader
• Hybrid work in Chicago: in-office Tuesday through Thursday, remote Mondays and Fridays, plus 20 additional flex remote days annually and 5 company-wide office-optional weeks tied to major holidays
• Remote flexibility available for exceptional candidates in California, Colorado, Florida, Georgia, Illinois, Indiana, Minnesota, Missouri, Montana, New Jersey, New York, North Carolina, Ohio, Oregon, Pennsylvania, South Carolina, Texas, Utah, Vermont, Virginia, Washington, Washington DC, and Wisconsin

About NinjaTrader

NinjaTrader is an industry-leading trading platform and futures broker with over 2 million users, serving as the number one rated futures brokerage worldwide. The company empowers traders with award-winning software and brokerage services to navigate global financial markets, and continues to modernize the futures industry through constant innovation.