Sr. Software Engineer (Scala)

NinjaTrader; Chicago (IL); On-site; USD 125,000 - 175,000; Full time

Benefits offered by this job

401k with company match

Generous PTO

Paid holidays

Life and disability insurance

Job summary

NinjaTrader is seeking a backend software engineer to design and implement Scala-based services for evaluation, risk, and trading workloads. You will build actor-based systems, own features end-to-end, and contribute to data models and event-driven architectures.

You'll work with PostgreSQL, Protobuf, and gRPC, diagnosing complex issues, and mentoring colleagues while supporting NinjaTrader’s evolution as a leading retail trading platform.

Qualifications

• 5+ years backend software engineering building real-time data systems.
• Strong Scala expertise with functional patterns and ScalaTest or equivalent.
• Experience with actor-based concurrency models (Akka, Pekko, etc.).
• Solid PostgreSQL skills: schema design, indexing, queries; JSONB usage knowledge.
• Familiarity with event-driven architectures and Kafka or Pub/Sub.
• Experience with Protobuf, gRPC, or schema-based service contracts.
• Ability to write technical specs, scope work, and identify risks early.
• Commitment to code quality, tests, docs, and PR reviews.
• Experience with trading platforms, fintech, or capital markets tech.

Responsibilities

• Design and implement backend services in Scala for evaluation, risk, and trading workloads.
• Build and evolve actor-based systems to handle high-throughput market data and events.
• Own features end-to-end from specs to production handoff.
• Design data models and DB changes in PostgreSQL, including JSONB usage.
• Diagnose production incidents by log analysis and tracing distributed flows.
• Maintain code quality with thorough PR reviews, tests, and instrumentation.
• Collaborate with Trading Services, Solutions Engineering, and Product on stories.
• Contribute to architectural decisions and debt remediation.
• Mentor junior engineers on Scala and reliable incident response.
• Develop deep expertise in NinjaTrader’s evaluation platform and integrations.

Skills

Scala

Akka

PostgreSQL

Kafka

gRPC

Protobuf

Observability

Backend design

Mentoring

Education

Bachelor's degree in CS or equivalent

Tools

Datadog

Pub/Sub

Job description

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.

What you’ll do:

• Design and implement backend services in Scala for evaluation, risk, and trading service workloads, including real‑time auto‑liquidation, account state management, and post‑trade processing
• Build and evolve actor‑based systems, such as Akka or similar technologies, that handle high‑throughput market data, position changes, and event‑driven workflows
• Own significant features end‑to‑end, from technical specifications through implementation, code review, and production handoff
• Design data models and database changes in PostgreSQL, including JSONB where appropriate, and contribute to the shared master schema, Protobuf, and SQL repositories
• Diagnose and resolve complex backend issues, including production incidents, by analyzing logs, tracing distributed flows, and reproducing edge cases under realistic loads
• Drive code quality across the team through thorough pull request reviews, clear acceptance criteria, disciplined development testing, and proper instrumentation and observability
• Collaborate with Trading Services, Solutions Engineering, and Product to translate business requirements into well‑scoped, accurately estimated stories
• Contribute to architectural decisions and long‑term technical debt remediation, including modernizing legacy Scala services and evaluating new event bus technologies
• Mentor junior team members on Scala idioms, functional design, testing practices, and incident response
• Develop deep expertise in NinjaTrader’s evaluation platform and partner integrations to provide authoritative backend leadership

What you’ll need:

• 5+ years of backend software engineering experience building production systems that handle real‑time data, concurrency, and high availability
• Strong, hands‑on Scala expertise, including idiomatic Scala, functional patterns, testing with ScalaTest or similar tools, and comfort working in a large, existing Scala codebase
• Experience with actor‑based concurrency models, such as Akka, Pekko, or equivalent technologies, including an understanding of supervision, message passing, and backpressure
• Solid relational database skills with PostgreSQL, including schema design, indexing, query optimization, and sound judgment about when to use JSONB versus a normalized structure
• Comfort with event‑driven architectures, message buses such as Kafka or Pub/Sub, and asynchronous workflows
• Excellent troubleshooting skills, with the ability to read logs, trace requests across distributed systems, and isolate root causes under pressure
• Demonstrated ability to write clear technical specifications, scope work realistically, and identify risks early
• High standards for code, tests, documentation, and pull requests, along with a willingness to uphold those standards during code reviews
• Ability to think on your feet and adapt quickly when priorities shift or unexpected issues arise
• Outstanding written and verbal communication skills, with the ability to explain backend tradeoffs to technical and non‑technical audiences
• Self‑starter who thrives in ambiguity and can manage multiple complex backend initiatives simultaneously
• Experience with trading platforms, fintech, or capital markets technology
• Understanding of trading concepts, including order routing, market data, position management, risk and liquidation logic, and profit and loss calculations
• Familiarity with Protobuf, gRPC, or schema‑based service contracts
• Experience migrating or modernizing legacy Scala systems or evaluating transitions from Scala to Rust or Go
• Background in observability, including distributed tracing, structured logging, and metrics using Datadog, Google Cloud Platform, or similar technologies
• Prior experience supporting enterprise or business‑to‑business partner integrations

Compensation:

The salary range for this role will be $125,000.00 - $175,000.00 USD. In addition, this position will also receive an annual target bonus of 12%. Bonus pay at NinjaTrader is based on individual performance (50%) as well as company/team performance (50%).

Salary and bonus earnings are only two components of the total compensation package offered by NinjaTrader. NinjaTrader offers a 401K plan through ADP under which the company will match up to 3.5% of employee contributions. Annual paid time off allowance accrues at a rate of 18 days per year (some positions may qualify for more) plus seven paid holidays.

Location:

This role is based in Chicago, IL. *There may be remote flexibility for exceptional candidates in the following states: 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, Wisconsin.

Hybrid:

For Chicago‑based employees, we follow a hybrid work schedule: In‑office Tuesday through Thursday, with remote work on Mondays and Fridays. In addition to these weekly remote days, we offer:

• 20 additional flex remote days annually
• 5 Company Wide Office‑Optional weeks tied to major holidays

Our Core Benefits Include:

• Generous PTO
• 7 Paid Holidays Annually + 5 Conditional Holidays Annually
• 1 Service Day Annually
• 401k with 3.5% Company Match
• Life and Disability Insurance Covered 100% by NinjaTrader

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.