Sr. Software Engineer I, Evaluation Services (Scala)

JOIN US ON OUR MISSION TO BECOME THE #1 RETAIL TRADING PLATFORM IN THE WORLD Welcome to the dynamic world of NinjaTrader! As an industry-leading trading platform and futures broker, we're empowering traders to take control of their financial destiny. How do we do it? We provide cutting-edge products and services that enhance the trading journey. Whether a seasoned pro or just starting out, NinjaTrader equips traders with award-winning software and brokerage services to navigate the world's leading financial markets with confidence. Our growth story is nothing short of exhilarating. Since 2003, NinjaTrader has been dedicated to understanding and supporting traders on their journey toward trading triumph. Through those efforts, our user base has grown to over 2 million users and we have become the number one rated futures brokerage worldwide. But we're not stopping there. We're constantly evolving, pushing boundaries, and modernizing the futures industry. Our commitment to innovation means users will always have access to dynamic tools, real-time support, and a community of like-minded traders. So, why work at NinjaTrader? Here, you're not just part of a team; you're part of a movement. We empower employees to reach new heights in their careers by providing a dynamic culture focused on social connection, professional development, and employee recognition initiatives. Sounds too good to be true? Take it from our employees. Join us as we redefine what's possible in trading, advocate for our customers, and continue our journey toward becoming the world's top retail-focused trading platform in the world. The team NinjaTrader is a futures-focused brokerage offering low commissions, award-winning trading platforms, and a suite of customizable tools for active traders. The platform delivers integrated multi-device trading across desktop, web, and mobile, with access to thousands of third-party trading apps and add-ons. The opportunity Our Evaluation Services team powers funded trader programs that give aspiring traders a pathway to professional trading capital. As a Sr. Software Engineer, you will design, build, and maintain the Scala-based backend systems behind our auto-liquidation engine, risk evaluation, and trading services, the core systems our platform and partners depend on. You will own complex backend problems end-to-end and work alongside Trading Services Engineers, frontend engineers, QA, and solutions engineers to deliver high-quality, production-ready features in a fast-paced environment. In This Role You Will Design and implement Scala backend services for evaluation, risk, and trading services workloads, including real-time auto-liquidation, account state management, and post-trade processingBuild and evolve actor-based systems (Akka or similar) that handle high-throughput market data, position changes, and event-driven workflowsOwn significant features end-to-end, from technical spec through implementation, code review, and production hand-offDesign data models and database changes (PostgreSQL, including JSONB where appropriate) and contribute to the shared master schema, Protobuf, and SQL repositoriesDiagnose and resolve complex backend issues, including production incidents, by analyzing logs, tracing distributed flows, and reproducing edge cases under realistic loadDrive code quality across the team through thorough PR reviews, clear acceptance criteria, dev-testing discipline, and proper instrumentation and observabilityCollaborate with Trading Services, Solutions Engineering, and Product to translate business requirements into well-scoped, well-estimated storiesContribute to architectural decisions and long-term tech-debt remediation, including modernization of legacy Scala services and evaluation of new event-bus technologiesMentor junior team members on Scala idioms, functional design, testing practices, and incident responseDevelop deep expertise in NinjaTrader's evaluation platform and partner integrations to provide authoritative backend leadership What You Bring 5+ years of backend software engineering experience building production systems that handle real-time data, concurrency, and high availabilityStrong, hands-on Scala expertise, including idiomatic Scala, functional patterns, testing (ScalaTest or similar), and comfort working in a large existing Scala codebaseExperience with actor-based concurrency models (Akka, Pekko, or equivalent), including supervision, message passing, and back-pressureSolid relational database skills with PostgreSQL, including schema design, indexing, query optimization, and judgment on when JSONB is appropriate vs. when a normalized structure is correctComfort with event-driven architectures, message buses (Kafka, Pub/Sub, or similar), and asynchronous workflowsExcellent troubleshooting skills with the ability to read logs, trace requests across distributed systems, and isolate root cause under pressureDemonstrated ability to write clear technical specs, scope work realistically, and flag risk earlyHigh quality standards on code, tests, documentation, and PRs, and willingness to enforce the same standards in code reviewOutstanding written and verbal communication skills with the ability to translate backend tradeoffs for both technical and non-technical audiencesSelf-starter who thrives in ambiguity, adapts quickly when priorities shift, and can manage multiple complex backend efforts simultaneously Nice to haves Experience with trading platforms, fintech, or capital markets technologyUnderstanding of trading concepts such as order routing, market data, position management, risk and liquidation logic, and P&L calculationFamiliarity with Protobuf, gRPC, or schema-based service contractsExperience migrating or modernizing legacy Scala systems, or evaluating Scala to Rust/Go transitionsBackground in observability, including distributed tracing, structured logging, and metrics (Datadog, GCP, or similar)Prior experience supporting enterprise or B2B partner integrations We are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender, gender identity or expression, or veteran status. We are proud to be an equal opportunity workplace. Compensation Range: $96K - $192K