Sr. Mobile Engineer II

NinjaTrader; Chicago (IL); Hybrid; USD 140,000 - 190,000; Full time

Benefits offered by this job

Generous PTO

Paid holidays

401k with Company Match

Parental leave

Health coverage

Life & Disability Insurance

Job summary

NinjaTrader in Chicago, IL is seeking a Sr. Software Engineer II specialized in Flutter to lead mobile architecture, mentor engineers, and deliver scalable, cross‑platform apps.

You will shape technical direction, maintain robust testing, and collaborate with Product and Design to enhance the user experience on iOS and Android. We offer a hybrid work model with in-office Tue–Thu and remote days, plus generous benefits.

Qualifications

• 6+ years of professional software engineering experience.
• 2+ years hands-on Flutter and Dart in production.
• Understanding of mobile architecture, state management, and design patterns.
• Experience with Flutter testing strategies (unit/widget/integration/e2e).
• Familiarity with CI/CD for mobile delivery.
• Experience with RESTful APIs, WebSockets, offline data handling.
• Strong communication and Agile collaboration.
• Solid OOP design principles.

Responsibilities

• Own the feature life cycle: debugging, documenting, testing, releasing, and monitoring.
• Attend daily stand-ups and team meetings to discuss tasks.
• Contribute to the mobile architecture roadmap, frameworks, and tooling.
• Participate in design reviews across iOS and Android.
• Implement robust Flutter solutions with proper state management and DI.
• Collaborate with Product and Design to improve mobile UX.
• Investigate issues, mitigate, and implement preventive measures.
• Improve observability, monitoring, and crash analytics.
• Foster technical excellence, innovation, and collaboration.

Skills

Flutter

Dart

Mobile Architecture

State Management

Testing

CI/CD

REST APIs

WebSockets

OOP

Job description

Disclaimer: Please be advised that the most accurate and up-to-date information about our open roles—including job descriptions, compensation, and benefits—can only be guaranteed on our official job board. For the latest listings and details, please visit: https://job-boards.greenhouse.io/ninjatrader.

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:

Join our Mobile Engineering team as a Sr. Software Engineer II specializing in Flutter. You will champion the execution of our mobile architecture, mentor engineers, and deliver scalable, high-performance applications that provide a seamless cross-platform experience. You will also shape technical direction across teams, set a high standard for engineering excellence, and drive quality and reliability across our mobile products.

In this role you will:

• Own the life cycle of features through debugging, documenting, testing, releasing, and monitoring
• Attend daily stand-ups and regular team-wide meetings to discuss current and upcoming tasks
• Contribute to the technical roadmap for mobile architecture, frameworks, and tooling
• Participate in design reviews, architecture discussions, and performance optimization efforts across iOS and Android
• Implement robust, maintainable Flutter solutions that follow best practices for state management, dependency injection, and reactive programming
• Collaborate with Product and Design teams to iteratively improve the user experience oncmobile platforms
• Investigate issues, mitigate them, and recommend preventative measures
• Improve observability, monitoring, and crash analytics to ensure product stability and quality
• Foster a culture of technical excellence, innovation, and collaboration

What you'll need:

• 6+ years of professional software engineering experience
• 2+ years of hands-on Flutter and Dart experience in production environments
• Understanding of mobile architecture, state management, and design patterns (e.g. BLoC, MVVM, Clean Architecture)
• Experience maintaining testing strategies for Flutter applications, spanning unit, widget, integration, and end-to-end levels
• Familiarity with building CI/CD automation for mobile delivery
• Understanding of RESTful APIs, WebSockets, and offline data handling
• Familiarity optimizing performance, reliability, and user experience across diverse devices
• Ability to perform in a team environment adopting agile principles
• Strong written and verbal communication skills
• Strong grasp of OOP design principles

Bonus Points for:

• Knowledge of native iOS (Swift) and Android (Kotlin/Java) integration
• Experience with fintech or trading platforms
• Contributions to open-source frameworks or SDKs

Compensation:

The salary range for this role will be $140,000.00 - $190,000.00 USD. In addition, this position will also receive an annual target bonus of 10%. 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
• Paid Parental Bonding Leave
• Health, Vision, Dental Coverage
• 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.